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Cutler-Hammer

Instructions for Installation, Operation and Maintenance of the Cutler-Hammer Digitrip 3000 Protective Relay

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TABLE OF CONTENTS

PAGE

SECTION 1 INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

1-1 Preliminary Comments and Safety Precautions..................................................................................................11-1.1 Warranty and Liability Information..........................................................................................................11-1.2 Safety Precautions .................................................................................................................................1

1-2 General Information.............................................................................................................................................11-3 Functions/Features/Options ................................................................................................................................21-4 Standards ............................................................................................................................................................5

SECTION 2 FUNCTIONAL DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

2-1 Protection, Testing and Communication Capabilities..........................................................................................62-1.1 RMS Sensing .........................................................................................................................................62-1.2 Pickup Setting ........................................................................................................................................62-1.3 Time Setting ...........................................................................................................................................62-1.4 Protection Curve Settings.......................................................................................................................62-1.5 Integral Testing.....................................................................................................................................102-1.6 Communications...................................................................................................................................10

2-2 Protective Relay Hardware................................................................................................................................112-2.1 Front Operations Panel ........................................................................................................................112-2.2 Rear Access Panel ...............................................................................................................................142-2.3 External Hardware................................................................................................................................16

2-3 UL Testing and Specification Summary ............................................................................................................16

SECTION 3 OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

3-1 Introduction........................................................................................................................................................183-2 Power-Up and Self Testing ...............................................................................................................................183-3 Panel Operations...............................................................................................................................................18

3-3.1 Characteristic Curve.............................................................................................................................183-3.2 Program Mode......................................................................................................................................243-3.3 Programming Overview........................................................................................................................263-3.4 Test Mode ............................................................................................................................................27

3-4 Communications Function.................................................................................................................................27

SECTION 4 APPLICATION CONSIDERATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

4-1 Zone Interlocking Capabilities ...........................................................................................................................31

SECTION 5 INSTALLATION, STARTUP AND TESTING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

5-1 Introduction........................................................................................................................................................345-2 Panel Preparation..............................................................................................................................................34

5-2.1 Cutout...................................................................................................................................................345-2.2 Mounting...............................................................................................................................................34

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PAGE

5-3 Replacing Digitrip MV with Digitrip 3000 ...........................................................................................................345-4 Wiring ................................................................................................................................................................355-5 Initial Startup .....................................................................................................................................................35

5-5.1 Before Power Application .....................................................................................................................355-5.2 Initial Power Application .......................................................................................................................36

5-6 Miscellaneous Testing.......................................................................................................................................36

SECTION 6 MAINTENANCE AND STORAGE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

6-1 General .............................................................................................................................................................376-1.1 Storage.................................................................................................................................................37

6-2 Troubleshooting Guide (Table 6-1) ...................................................................................................................376-3 Replacement .....................................................................................................................................................37

SECTION 7 TIME CURRENT CURVES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

7-1 Digitrip 3000 Inverse Time Overcurrent Curves ................................................................................................407-2 Digitrip 3000 Curve Equations...........................................................................................................................60

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FIGURES

Figure Title Page

1-1 Digitrip 3000 Protective Relay (Front View)...............................................................................................11-2 Digitrip 3000 Protective Relay (Rear and Side Views) ..............................................................................21-3 A Digitrip 3000 Protective Relay Installed on a Metal Assembly Panel with a DP-4000 ...........................31-4 Digitrip 3000 Protective Relay with DIP Switches Shown in Upper Left (Rear View)................................31-5 Digitrip 3000 Curve Shape Possibilities.....................................................................................................41-6 Installed Jumpers in Place on Terminal Block TB-1 Disabling the

Zone Interlocking Feature..........................................................................................................................5

2-1 Typical Communications Wiring Diagram................................................................................................12

3-1 Digitrip 3000 Typical Wiring Diagram ......................................................................................................193-2 Digitrip 3000 Time-Current Characteristic Curves...................................................................................203-3 Sample Electronic Curves .......................................................................................................................213-4 Typical Inverse Time Overcurrent Pickup Horizontal Movement.............................................................213-5 Typical Time Multiplier Adjustment (I2T Response).................................................................................223-6 Short Delay Setting Adjustment...............................................................................................................223-7 Short Delay Time Adjustment ..................................................................................................................223-8 Typical is Curve with I2T Slope................................................................................................................233-9 Instantaneous Setting Adjustment ...........................................................................................................233-10 Programming Sequence Preview ............................................................................................................263-11 Local Programming Sequence Flow Chart ..............................................................................................28

4-1 Connection Diagram for Typical Phase Zone Selective Interlocking.......................................................324-2 Connection Diagram for Typical Ground Zone Selective Interlocking .....................................................33

5-1 Cutout Dimensions (Inches) ....................................................................................................................345-2 Digitrip 3000 Protective Relay Dimensions (Inches)................................................................................35

7-1 Inverse Time Overcurrent Phase, I4T Curves (SC-5390-92B) ................................................................417-2 Inverse Time Overcurrent Phase, I2T Curves (SC-5391-92B) ................................................................427-3 Inverse Time Overcurrent Phase, IT Curves (SC-5392-92B)..................................................................437-4 Inverse Time Overcurrent Phase, Flat Curves (SC-5393-92B) ...............................................................447-5 Short Delay Phase Curves (SC-5394-92B) .............................................................................................457-6 Inverse Time Overcurrent/Short Delay Curves (SC-5395-92B)...............................................................467-7 Instantaneous Curves (SC-5396-92B).....................................................................................................477-8 Inverse Time Overcurrent Ground, I4T Curves (SC-5399-92B)...............................................................487-9 Inverse Time Overcurrent Ground, I2T Curves (SC-5400-92B)...............................................................497-10 Inverse Time Overcurrent Ground, IT Curves (SC-5401-92B) ................................................................507-11 Inverse Time Overcurrent Ground, Flat Curves (SC-5402-92B) .............................................................517-12 Short Delay Ground Curves (SC-5403-92B) ...........................................................................................527-13 ANSI Moderately Inverse Curves (SC-6685-96)......................................................................................537-14 ANSI Very Inverse Curves (SC-6686-96) ................................................................................................547-15 ANSI Extremely Inverse Curves (SC-6687-96) .......................................................................................557-16 IEC-A Moderately Inverse Curves (SC-6688-96) ....................................................................................567-17 IEC-B Very Inverse Curves (SC-6689-96)...............................................................................................577-18 IEC-C Extremely Inverse Curves (SC-6690-96) ......................................................................................587-19 IEC-D Flat Curves (SC-6691-96).............................................................................................................59

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TABLES

Table Title Page

2.1 Curve Selection .........................................................................................................................................62.2 Characteristic for Phase Element ..............................................................................................................72.3 Characteristic for Ground Element ............................................................................................................82.4 Miscellaneous Settings..............................................................................................................................92.5 Factory Set Defaults ................................................................................................................................10

3.1 Digitrip 3000 Curve Shapes.....................................................................................................................183.2 Digitrip 3000 Display Messages ..............................................................................................................30

5.1 Digitrip 3000 Dip Switch Settings.............................................................................................................36

6.1 Troubleshooting Guide ............................................................................................................................38

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SECTION 1: INTRODUCTION

1-1 PRELIMINARY COMMENTS AND SAFETY PRE-CAUTIONS

This technical document is intended to cover mostaspects associated with the installation, application,operation and maintenance of the Cutler-HammerDigitrip 3000 Protective Relay. This document is provid-ed as a guide for authorized and qualified personnelonly in the selection and application of the Digitrip 3000Protective Relay. Please refer to the specific WARNINGand CAUTION in Section 1-1.2 before proceeding. If fur-ther information is required by the purchaser regarding aparticular installation, application or maintenance activi-ty, a Cutler-Hammer representative should be contact-ed.

1-1.1 WARRANTY AND LIABILITY INFORMATION

NO WARRANTIES, EXPRESSED OR IMPLIED,INCLUDING WARRANTIES OF FITNESS FOR A PAR-TICULAR PURPOSE OF MERCHANTABILITY, ORWARRANTIES ARISING FROM COURSE OF DEAL-ING OR USAGE OF TRADE, ARE MADE REGARDINGTHE INFORMATION, RECOMMENDATIONS ANDDESCRIPTIONS CONTAINED HEREIN. In no event willCutler-Hammer be responsible to the purchaser or userin contract, in tort (including negligence), strict liability orotherwise for any special, indirect, incidental or conse-quential damage or loss whatsoever, including but notlimited to damage or loss of use of equipment, plant orpower system, cost of capital, loss of power, additionalexpenses in the use of existing power facilities, orclaims against the purchaser or user by its customersresulting from the use of the information and descrip-tions contained herein.

1-1.2 SAFETY PRECAUTIONS

All safety codes, safety standards and/or regulationsmust be strictly observed in the installation, operationand maintenance of this device.

THE WARNINGS AND CAUTIONS INCLUDED ASPART OF THE PROCEDURAL STEPS IN THIS DOCU-MENT ARE FOR PERSONNEL SAFETY AND PRO-TECTION OF EQUIPMENT FROM DAMAGE. ANEXAMPLE OF A TYPICAL WARNING LABEL HEAD-ING IS SHOWN ABOVE TO FAMILIARIZE PERSON-

NEL WITH THE STYLE OF PRESENTATION. THISWILL HELP TO INSURE THAT PERSONNEL AREALERT TO WARNINGS, WHICH MAY APPEARTHROUGHOUT THE DOCUMENT. IN ADDITION,CAUTIONS ARE ALL UPPER CASE AND BOLDFACE.

COMPLETELY READ AND UNDERSTAND THEMATERIAL PRESENTED IN THIS DOCUMENTBEFORE ATTEMPTING INSTALLATION, OPERATIONOR APPLICATION OF THE EQUIPMENT. IN ADDI-TION, ONLY QUALIFIED PERSONS SHOULD BEPERMITTED TO PERFORM ANY WORK ASSOCIAT-ED WITH THE EQUIPMENT. ANY WIRING INSTRUC-TIONS PRESENTED IN THIS DOCUMENT MUST BEFOLLOWED PRECISELY. FAILURE TO DO SOCOULD CAUSE PERMANENT EQUIPMENT DAMAGE.

1-2 GENERAL INFORMATION

The Digitrip 3000 Protective Relay is a panel mountedmulti-function, microprocessor based overcurrent relay,designed for both ANSI and IEC applications (Figures 1-1 and 1-2). It is a self-contained device which operates

! CAUTION

! WARNING

Figure 1-1 Digitrip 3000 Protective Relay (Front View)

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from either AC or DC control power, and provides trueRMS sensing of each phase and ground current. Onlyone relay is required per three-phase circuit. Currentmonitoring and operator selectable protective functionsare integral to each device.

THE LOSS OF CONTROL VOLTAGE WILL CAUSETHE DIGITRIP 3000 TO BE INOPERATIVE. IF ACCONTROL VOLTAGE IS USED, AN APPROPRIATERELIABLE POWER SOURCE/SCHEME SHOULD BESELECTED (POSSIBLY A UPS SYSTEM) TO SUPPLYPOWER TO THE RELAY.

The Digitrip 3000 Protective Relay provides protectionfor most types of medium voltage electrical power distri-bution systems. It was designed for use with Cutler-Hammer Type VCP-W vacuum circuit breakers, as wellas other manufacturers’ medium and high voltage circuitbreakers (Figure 1-3). Digitrip 3000 Protective Relaysare compatible for use with all circuit breakers utilizing ashunt trip coil. Thermal curves, plus ANSI and IEC

inverse time overcurrent curves provide close coordina-tion with both downstream and upstream protectivedevices. One Digitrip 3000 Protective Relay replacesthe normal complement of three or four conventionalelectro-mechanical overcurrent relays, an ammeter, ademand ammeter, an ammeter switch, and, in some sit-uations, a lockout relay switch (device 86). All Digitrip3000 Protective Relays include a built-in INCOM com-munication capability compatible with the Cutler-Hammer IMPACC system.

1-3 FUNCTIONS/FEATURES/OPTIONS

The primary function of the Digitrip 3000 ProtectiveRelay is overcurrent protection. This is achieved by ana-lyzing the secondary current signals received from theswitch-gear current transformers. When predeterminedcurrent levels and time delay settings are exceeded, theclosing of trip contact(s) is used to initiate breaker trip-ping.

The Digitrip 3000 Protective Relay operates from thesecondary output of standard switchgear current trans-formers rated at In = 5 amperes. It is operator configured

Figure 1-2 Digitrip 3000 Protective Relay (Rear and Side Views)

! CAUTION

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Figure 1-3 A Digitrip 3000 Protective Relay (right)Installed on a Metal Assembly Panel with a DP-4000 (left)

Figure 1-4 Digitrip 3000 Protective Relay with DIPSwitches Shown in Upper Left (Rear View)

to fit specific distribution system requirements. The cur-rent transformer ratio information is programmed intoDigitrip 3000 by setting pushbuttons located on the face-plate of the relay. The phase and ground CT ratios canbe independently programmed over a range of 5:5 to5000:5. Refer to Table 2.4 for all available CT ratio set-tings.

Protective functions are also configured by using thepushbuttons on the faceplate of the relay. These protec-tive functions can be programmed with the circuit break-er in the open or closed position. DIP Switch S2, locatedon the rear of the relay, is used to control closed breakersetting ability (Figure 1-4). Refer to paragraph 2-2.2 andTable 5.1 for additional information. Inverse time over-current protection for the phase element cannot be dis-abled. This insures that all phase protection cannot bedisabled. The relay also automatically exits the programmode, if there is no programming activity for 2-1/2 min-utes. Programming and test mode security is provided bya sealable, hinged access cover on the front of the relay.Direct reading displays indicate the value currently beingconsidered, while multi-colored LEDs indicate opera-tional conditions and specific functions (Figure 1-1).

In addition to performing a continuous self-testing ofinternal circuitry as a part of normal operation, all

Digitrip 3000 Protective Relays include a front accessi-ble, integral field testing capability. In the integral testmode, a test current simulates an overload or short cir-cuit condition, to check that all tripping features arefunctioning properly. The test function is user selectableto trip or not trip the breaker. Refer to Paragraph 2-1.5for additional information.

The Digitrip 3000 Protective Relay provides five protec-tive functions for both phase and ground protection. Theground element is capable of a residual, an externalsource ground or a zero sequence connection. If groundprotection is not desired, the ground element does nothave to be connected.

The five protective settings are:

• Inverse Time Overcurrent Pickup• Inverse Time Overcurrent Time Multiplier• Short Delay Pickup• Short Delay Time• Instantaneous Pickup

Each of the protective functions are independently pro-grammed for various combinations to fit specific systemrequirements. For protective functions not required, therelay will allow all of the protective functions on ground

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and all but the inverse time overcurrent function onphase to be disabled. When the Digitrip 3000 is not setfor an instantaneous trip function, a true making currentrelease (discriminator) is available. If not desired, thediscriminator can be disabled.

Digitrip 3000 Protective Relays provide greater selectivecoordination potential by providing 11 different curveshapes (Figure 1-5).

• Thermal Curves (4 shapes)- It- I2t- I4t- Flat

• ANSI Curves (3 shapes per ANSI C37.112)- Moderately Inverse- Very Inverse- Extremely Inverse

• IEC Curves (4 shapes per IEC 255-3)- IEC-A (Moderately Inverse)- IEC-B (Very Inverse)- IEC-C (Extremely Inverse)- IEC-D (Definite Time)

The ground element of Digitrip 3000 can have a curveshape independent of the phase element, providing fora more versatile ground protection.

With this vast selection of Curve Shapes, Digitrip 3000provides protection capable of coordinating with mostany existing electro-mechanical overcurrent relay orpower fuse.

A pictorial representation of characteristic curve shapesis provided on the face of the relay for reference purpos-es (Figure 1-1).

All Digitrip 3000 Protective Relays have zone selectiveinterlocking capabilities for phase and ground fault pro-tection. Zone selective interlocking is a means by whichtwo or more coordinated trip devices can communicateto alter their pre-set tripping modes to provide a fasterresponse for certain upstream fault conditions. The relayis shipped with the zone selective interlocking featuredisabled by the use of the two jumpers on the rearmounted terminal strip TB1(Figure 1-6).

Digitrip 3000 Protective Relays operating parametersand troubleshooting information are displayed on thefront of the relay, via the two display windows. This isconsidered “ON DEVICE” information. In addition, allrelay information can be transmitted to a remote locationvia the built-in INCOM communication system. This typeof information is referred to as “COMMUNICATEDINFORMATION.” In addition to being able to provide acircuit breaker “OPEN” or “CLOSED” status to theremote location, the Digitrip 3000 displays and remotelytransmits parameters, such as:

Figure 1-5 Digitrip 3000 Curve Shape Possibilities

TIM

E

CURRENT

I4t

I2t

It

FLAT

(Curve Shape)

(Short Delay)

(Instantaneous)

TIM

E

CURRENT

(Curve Shape)

(Short Delay)

(Instantaneous)

XTRM

VERY

MOD

TIM

E

CURRENT

IEC-C IEC-B

IEC-A

(Curve Shape)

(Short Delay)

(Instantaneous)IEC-D

Thermal Curves ANSI Curves➀ IEC Curves➁

➀ ANSI Curve shapes defined by ANSI C37.112.➁ IEC Curve shapes defined by IEC 255-3.

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• Individual phase currents• Ground current• Maximum current for each phase and ground since

last reset (Amp. Demand)• Magnitude and phase of current causing trip• Cause of trip• Current transformer ratio• Existing setpoint settings

The remote communications capability is made possibleby the Cutler-Hammer Integrated Communications(INCOM) Chip and Protocol compatible with theIMPACC Monitor and Control System. The protocol per-mits a remote master computer to perform:

(1) Interrogation of relay data (2) Execution of circuit breaker

“Close” and“Trip” commands(3) “Reset” of the relay after a trip(4) Downloading of settings

Reliable two-way communications can be provided overa twisted pair communications network. The Digitrip3000 Protective Relay is supplied with a built-in commu-nications capability compatible with the Cutler-HammerIMPACC system.

1-4 STANDARDS

Digitrip 3000 Protective Relays are “ComponentRecognized” by the Underwriters Laboratory, Inc.®under UL File E154862. Refer to Section 2-3 UL Testingand Specification Summary for more information.

Figure 1-6 Installed Jumpers in Place on TerminalBlock TB-1 Disabling the Zone Interlocking Feature

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SECTION 2: FUNCTIONAL DESCRIPTION

2-1 PROTECTION, TESTING AND COMMUNICATIONCAPABILITIES

2-1.1 RMS SENSING

Digitrip 3000 Protective Relays provide true RMS sens-ing for proper correlation with the thermal characteristicsof conductors and equipment. The root mean square(rms) value is determined by a microprocessor calcula-tion of discrete sampled points of the current waveform.This root mean square value is used for the protectionresponse and metering displays of the relay.

2-1.2 PICKUP SETTING

A Digitrip 3000 Protective Relay pickup setting is a dis-crete, preselected value of current used to initiate a trip-ping action. The Digitrip 3000 has several current basedtripping functions:

• Phase inverse time overcurrent tripping - Thermal,ANSI, and IEC Curves.

• Ground inverse time overcurrent tripping - Thermal,ANSI, and IEC Curves. Ground selection is indepen-dent of phase selection.

• Phase and ground short delay tripping.

• Phase and ground instantaneous tripping.

As shown in Figure 3-2, the ANSI and IEC “CurveShapes” are in terms of multiples of Ipu (PickupCurrent of the CT Primary), whereas “short delay”and “instantaneous” are in terms of multiples of In(5A secondary of CT primary current). The thermalcurve is represented in terms of multiples of In for itscurve shape, short delay, and instantaneous set-tings. This must be considered in the coordinationstudy and in the programming of the Digitrip 3000Protective Relay.

Example: Thermal Curves, Short Delay andInstantaneous settings using In

CT Rating = In = 1200A.Pickup Setting = 1.5Pickup (amps) = (1200)(1.5)

= 1800A.

Example: ANSI and IEC curves using IpuCT Rating = 1200A.Ipu = Pickup Current = 1800A.CT Ratio = 1200:5 (Entered as “1200”)Actual secondary current at pickup =

7.5A. = (1800/1200) x 5

2-1.3 TIME SETTING

A Digitrip 3000 Protective Relay time setting is a prese-lected time delay initiated when a pickup point on thelong or short curve is exceeded. If the current valuedrops below the pickup value, the timing function resets.No memory is provided. If the current value does notdrop below pickup, the amount of delay before trippingoccurs is a function of the current magnitude and thetime setting. The delay can be determined from theappropriate time-current curves.

2-1.4 PROTECTION CURVE SETTINGS

Curve Selection: Extensive flexibility on inverse timeovercurrent (phase and ground) curve shaping is possi-ble with eleven available curve types. The selection andassociated result is determined by the type of curveshape that best fits the coordination requirements(Figure 1-5, Table 2.1). Different curve shape settings

Table 2.1 Curve Selection

Curve Type Selection Result

Thermal It Moderately Inverse

I2t Inverse

I4t Extremely Inverse

FLAT Definite or Fixed Time

ANSI MOD Moderately Inverse

VERY Very Inverse

XTRM Extremely Inverse

IEC IEC-A Moderately Inverse

IEC-B Very Inverse

IEC-C Extremely Inverse

IEC-D Definite Time

NOTICE

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Table 2.2 Characteristic for Phase Element

CURVE SHAPE IT, I2T, I4T, FLAT, MOD, VERY, XTRM, IECA, IECB, IECC, IECD

INVERSE TIME OVERCURRENT 0.20, 0.25, 0.30, 0.35, 0.40, 0.45, 0.50, + 5%PICKUP 0.55, 0.60, 0.65, 0.70, 0.75, 0.80, 0.85,

0.90, 0.95, 1.00, 1.10, 1.20, 1.30, 1.40,1.50, 1.60, 1.70, 1.80, 1.90, 2.00, 2.10, 2.20

INVERSE TIME OVERCURRENT Curve = IT, I2T, I4T:TIME MULTIPLIER 0.20, 0.25, 0.30, 0.35, 0.40, 0.45, 0.50, +10%➀ ➁ IT SC-5392-92B

0.55, 0.60, 0.65, 0.70, 0.75, 0.80, 0.85, I2T SC-5391-92B0.90, 0.95, 1.00, 1.25, 1.50, 1.75, 2.00, I4T SC-5390-92B2.25, 2.50, 2.75, 3.00, 3.50, 4.00, 4.50, 5.00, 5.50, 6.00, 6.50, 7.00, 7.50, 8.00, 8.50, 9.00, 10.0, 12.5, 15.0, 17.5, 20.0, 22.5, 25.0, 27.5, 30.0, 35.0, 40.0

Curve = FLAT:0.20, 0.25, 0.30, 0.35, 0.40, 0.45, 0.50, + 0.05 SEC FLAT 0.55, 0.60, 0.65, 0.70, 0.75, 0.80, 0.85, SC 5393-92B0.90, 0.95, 1.00, 1.25, 1.50, 1.75, 2.00

Curve = ANSI MOD, VERY, XTRM: +10%➀ ➂ MOD SC-6685-960.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, VERY SC-6686-961.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, XTRM SC-6687-961.9, 2.0, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9, 3.0, 3.1, 3.2, 3.3, 3.4, 3.5, 3.6, 3.7, 3.8, 3.9, 4.0, 4.1, 4.2, 4.3, 4.4, 4.5, 4.6, 4.7, 4.8, 4.9, 5.0

Curve = IECA, IECB, IECC, IECD: +10%➀ ➂ ➃ IECA SC-6688-960.05, 0.10, 0.15, 0.20, 0.25, 0.30, 0.35, IECB SC-6689-960.40, 0.45, 0.50, 0.55, 0.60, 0.65, 0.70, IECC SC-6690-960.75, 0.80, 0.85, 0.90, 0.95, 1.00 IECD SC-6691-96

SHORT DELAY PICKUP 1.00, 1.25, 1.50, 1.75, 2.00, 2.25, 2.50, + 10% SC-5394-92B2.75, 3.00, 3.50, 4.00, 4.50, 5.00, 5.50, 6.00, 6.50, 7.00, 7.50, 8.00, 8.50, 9.00, 9.50, 10.0, 11.0, NONE

SHORT DELAY TIME 0.05, 0.10, 0.15, 0.20, 0.25, 0.30, 0.35, + 0.05 SEC SC-5394-92B(In Seconds) 0.40, 0.45, 0.50, 0.55, 0.60, 0.65, 0.70,

0.75, 0.80, 0.85, 0.90, 0.95, 1.00, 1.25, 1.50

INSTANTANEOUS PICKUP 1.00, 1.25, 1.50, 1.75, 2.00, 2.25, 2.50, + 10% SC-5396-92B2.75, 3.00, 3.50, 4.00, 4.50, 5.00, 5.50, 6.00, 6.50, 7.00, 7.50, 8.00, 8.50, 9.00, 9.50, 10.0, 12.5, 15.0, 17.5, 20.0, 22.5, 25.0, NONE

DISCRIMINATOR D ON Fixed At 11 x In + 10%(If Phase INST set to NONE) D OFF

NOTES: ➀ Curves go to constant operating time above 30 x In.➁ Tolerance: ± 10% or 0.09 seconds, whichever is larger. Minimum operating trip time is 0.05 seconds.➂ Tolerance: ± 10% or 0.09 seconds, whichever is larger (>1.5 x Ipu). Minimum trip time is 2 power line cycles.➃ For IECD, the Time Multiplier Tolerance is ±0.05 seconds.

TYPE SETTING AVAILABLE SETTINGS TOLERANCE CURVE #

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CURVE SHAPE IT, I2T, I4T, FLAT, MOD, VERY, XTRM, IECA, IECB, IECC, IECD

INVERSE TIME OVERCURRENT 0.100, 0.125, 0.150, 0.175, 0.200, 0.225, + 5%PICKUP 0.250, 0.275, 0.300, 0.350, 0.400, 0.450,

0.500, 0.550, 0.600, 0.650, 0.700, 0.750, 0.800, 0.850, 0.900, 0.950, 1.00, 1.25, 1.50, 1.75, 2.00, NONE

INVERSE TIME OVERCURRENT Curve = IT, I2T, I4T:TIME MULTIPLIER 0.20, 0.25, 0.30, 0.35, 0.40, 0.45, 0.50, 0.55, +10%➀ ➁ ➄ IT SC-5401-92B

0.60, 0.65, 0.70, 0.75, 0.80, 0.85, 0.90, 0.95, I2T SC-5400-92BGround Time Multiplier setting options 1.00, 1.25, 1.50, 1.75, 2.00, 2.25, 2.50, 2.75, I4T SC-5399-92Bdepend upon Ground Curve setting 3.00, 3.50, 4.00, 4.50, 5.00, 5.50, 6.00, 6.50, selection. 7.00, 7.50, 8.00, 8.50, 9.00, 10.0, 12.5, 15.0,

17.5, 20.0, 22.5, 25.0, 27.5, 30.0, 35.0, 40.0

Curve = FLAT:0.20, 0.25, 0.30, 0.35, 0.40, 0.45,0.50, + 0.05 SEC FLAT 0.55, 0.60, 0.65, 0.70, 0.75, 0.80, 0.85, SC-5402-92B0.90, 0.95, 1.00, 1.25, 1.50, 1.75, 2.00

Curve = ANSI MOD, VERY, XTRM: +10%➀ ➂ ➄ MOD SC-6685-960.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, VERY SC-6686-961.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, XTRM SC-6687-962.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9, 3.0, 3.1, 3.2, 3.3, 3.4, 3.5, 3.6, 3.7, 3.8, 3.9, 4.0, 4.1, 4.2, 4.3, 4.4, 4.5, 4.6, 4.7, 4.8, 4.9, 5.0

Curve = IECA, IECB, IECC, IECD: +10%➀ ➂ ➃ ➄ IECA SC-6688-960.05, 0.10, 0.15, 0.20, 0.25, 0.30, 0.35, IECB SC-6689-960.40, 0.45, 0.50, 0.55, 0.60, 0.65, 0.70, IECC SC-6690-960.75, 0.80, 0.85, 0.90, 0.95, 1.00 IECD SC-6691-96

SHORT DELAY PICKUP 0.100, 0.125, 0.150, 0.175, 0.200, 0.225, + 10% SC-5403-92B0.250, 0.275, 0.300, 0.350, 0.400, 0.450, 0.500, 0.550, 0.600, 0.650, 0.700, 0.750, 0.800, 0.850, 0.900, 0.950, 1.00, 1.25, 1.50, 1.75, 2.00, 2.25, 2.50, 2.75, 3.00, 3.50, 4.00, 4.50, 5.00, 5.50, 6.00, 6.50, 7.00, 7.50, 8.00, 8.50, 9.00, 9.50, 10.0, 11.0, NONE

SHORT DELAY TIME 0.05, 0.10, 0.15, 0.20, 0.25, 0.30, 0.35, + 0.05 SEC SC-5403-92B(In Seconds) 0.40, 0.45, 0.50, 0.55, 0.60, 0.65, 0.70,

0.75, 0.80, 0.85, 0.90, 0.95, 1.00, 1.25, 1.50

INSTANTANEOUS PICKUP 0.50, 0.55, 0.60, 0.65, 0.70, 0.75, 0.80, + 10% SC-5396-92B0.85,0.90, 0.95, 1.00, 1.25, 1.50, 1.75, 2.00, 2.25, 2.50, 2.75, 3.00, 3.50, 4.00, 4.50, 5.00, 5.50, 6.00, 6.50, 7.00, 8.00, 8.50, 9.00, 9.50, 10.0, 11.0, NONE

Table 2.3 Characteristic for Ground Element

TYPE SETTING AVAILABLE SETTINGS TOLERANCE CURVE #

NOTES: ➀ Curves go to constant operating time above 30 x In.➁ Tolerance: ± 10% or 0.09 seconds, whichever is larger. Minimum operating trip time is 0.05 seconds.➂ Tolerance: ± 10% or 0.09 seconds, whichever is larger (>1.5 x Ipu). Minimum trip time is 2 power line cycles.➃ For IECD, the Time Multiplier Tolerance is ±0.05 seconds. ➄ For Ground Pickup ≤0.2pu: trip time tolerance is ±15%.

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can be applied to phase and ground to maximize coordi-nation flexibility. The curves are discussed in moredetail in paragraph 3-3.1.

Phase Inverse Time Overcurrent Pickup: The avail-able pickup settings, shown in Table 2.2, range from0.20 to 2.2 times (In).

Phase Inverse Time Overcurrent Time Multiplier:The available time settings, shown in Table 2.2, dependon the curve shape selected. For the thermal curves,the settings represent relay operating times at a currentvalue equal to 3 times (In). For ANSI and IEC curves,the settings represent the relay’s time multiplier for thecurrent value equal to I/Ipu.

Phase Short Delay Pickup: The available pickup set-tings, shown in Table 2.2, range from 1 to 11 times (In)or NONE. If NONE is selected, the short delay protec-tive function is disabled.

Phase Short Delay Time: The available time settings,shown in Table 2.2, range from 0.05 to 1.5 seconds atcurrents equal to or above the short delay pickup settingselected. If NONE was selected for the Phase ShortDelay Pickup Setting, the relay will bypass requestingthe time setting.

Phase Instantaneous: The available pickup settings,shown in Table 2.2, range from 1 to 25 times (In) or

NONE. If NONE is selected, the instantaneous protec-tive function is disabled and a choice of whether to turnthe discriminator option on (DON) or off (DOFF) isoffered. The discriminator is a true making currentrelease. When the circuit breaker closes, the discrimina-tor function, if selected to be on, is functional in aninstantaneous trip mode for 10 cycles after the breakercloses. The breaker will trip instantaneously via the dis-criminator, if the fault current is above 11 times (In).After the 10 cycle period has passed, the discriminatorwill no longer be functional. It becomes functional againonly when the breaker opens and then is reclosed.

Ground Fault: After the phase instantaneous setting isestablished, the ground curve shape, the ground inversetime overcurrent pickup, ground inverse time overcur-rent time, ground short delay pickup, ground short delaytime and ground instantaneous settings are selected.The available settings are shown in Table 2.3. Note thatthe ground curve settings are independent of the phasecurve and are programmed separately.

Programming the ground settings is done in the samemanner as the phase settings, except there is no dis-criminator option for ground instantaneous, and there isa NONE selection for the inverse time overcurrent pick-up setting.

High Load: The available high load time-out settingsare shown in Table 2.4. At a current 85% or above the

HIGHLOAD TIME 0 Sec, 5 Sec, 10 Sec, 30 Sec, 1 min, 2 min, 5 min,(pickup fixed @ 0.85 X Phase Time Overcurrent Setting)

FREQUENCY 50 Hz, 60 Hz

PHASE CT RATIO 5, 10, 25, 50, 75, 100, 150, 200, 250, 300, 400, 500, 600, 630,800, 1000, 1200, 1250, 1500, 1600, 2000, 2400, 2500, 3000,3200, 4000, 5000

GROUND CT RATIO 5, 10, 25, 50, 75, 100, 150, 200, 250, 300, 400, 500, 600, 630,800, 1000, 1200, 1250, 1500, 1600, 2000, 2400, 2500, 3000,3200, 4000, 5000

TESTPhase ...........................................................................P1, P2, P3, P4, P5, P6, P7, P8, P9, P10, P12, P14, P16

P18, P20, P22, P25

Phase Trip ....................................................................P3T, P10T, P25T

Ground..........................................................................G.1, G.2, G.3, G.4, G.5, G.6, G.7, G.8, G.9, G1, G2, G3, G4G5, G6, G8, G10

Ground Trip ..................................................................G1T, G3T, G10T

TYPE SETTING AVAILABLE SETTINGS

Table 2.4 Miscellaneous Settings

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inverse time overcurrent phase setting value, the highload function will begin timing to the time setting select-ed and the High Load LED will blink. If the current dropsbelow the 85% value, the high load timer will reset, andonly start again when the 85% value is again reached.When the high load timer times out, the “High Load”LED on the front of the relay lights continuously and analarm signal is sent over the communication network.

System Frequency Selection: Either 60Hz or 50Hzmay be selected (Table 2.4).

Phase and Ground CT Ratio Selection: The availableCT ratio’s, shown in Table 2.4, range from 5:5 to5000:5.

Defaults: In the unlikely event of missing or invalid set-tings, the Operational LED will blink Red instead ofGreen and the relay will display “PRGM” in the SettingsDisplay window. This means that the program of set-tings should be re-entered and saved.

2-1.5 INTEGRAL TESTING

Digitrip 3000 Protective Relays have a front accessible,integral field testing capability. This feature introduces aselected level of internal test current to simulate an over-load or short circuit. It checks proper functioning of therelay and verifies that curve settings have been set-upcorrectly. The integral test function provides selectable“Trip” and “No Trip” test settings for both phase andground testing. Refer to Table 2.4 for available test set-tings. The “P” used in Table 2.4 refers to a phase currenttest setting, while the “G” refers to a ground current testsetting. “T” in the table means that the test will initiate abreaker trip. All settings are in per unit current valuestimes the In value, which is the selected CT rating.

THE TEST MODE SHOULD NOT BE USED TO TRIPLIVE CURRENT CARRYING CIRCUITS. IF A LIVECURRENT OF GREATER THAN 0.1 TIMES THE (In)VALUE IS FLOWING IN EITHER A PHASE ORGROUND CIRCUIT, THE TEST MODE IS AUTOMATI-CALLY EXITED, ACCOMPANIED BY AN ERRORMESSAGE IN THE SETTINGS/TEST TIME/ TRIPCAUSE WINDOW.

2-1.6 COMMUNICATIONS

An important function of the Digitrip 3000 ProtectiveRelay is communications and control via the Cutler-

! CAUTION

DIP SWITCH SETTINGS

Type Default Setting

S1: ON (Digitrip 3000 IMPACC Buffers)S2: OFF (Program with Breaker Open Only)S3: OFF (Standard Relay Configuration -

OC/Instantaneous)S4: ON (Enable Remote Open/Close)S5: OFF (Reserved)S6: OFF (Reserved)S7: OFF (Reserved)S8: OFF (Disable Download Setpoints)S9: OFF (Manual Reset)S10: OFF (Reserved)

PHASE SETTINGS

Type Default Setting

Curve Shape: ItLDPU: 1.0LDT: 5 sec.SDPU: 1.5SDT: 1.0 sec.INST: 1.75

GROUND SETTINGS

Type Default Setting

Curve Shape: ItLDPU: 0.5LDT: 5 sec.SDPU: 0.75SDT: 1.0 sec.INST: 1.0

MISCELLANEOUS SETTINGS

Type Default Setting

DISC: OFFHILD: 10 sec.FREQ: 60 HzPCT: 500GCT: 500

Table 2.5 Factory Set Defaults

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Hammer Integrated Communications (INCOM) Protocol.It allows the combining of electrical distribution and con-trol products with personal computers into a comprehen-sive communications and control network.

The Digitrip 3000’s communications chip permits theinterrogation of relay data, remote tripping and closingof breaker, the Reset of the relay after a trip, and down-loading of set points from a remote master computer.Communications is accomplished from the relay to themaster computer via a 115.2 KHz. frequency carrier sig-nal over a shielded twisted pair of conductors. Thereceiving terminal is a remote mounted master comput-er (IBM compatible). Refer to Figure 2-1 for a typicalcommunications wiring diagram.

Ground shielding should be provided at one placeonly, with the computer end being the recommend-ed location.

2-2 PROTECTIVE RELAY HARDWARE

2-2.1 FRONT OPERATIONS PANEL

The operations panel, which is normally accessible fromthe outside of the switchgear panel door, provides ameans to program, monitor and test the unit (Figure 1-1). For the purpose of familiarization, the panel isdivided into three sub-sections:

1. Pushbuttons2. LEDs3. Display Windows

Pushbuttons: The front operations panel supportseleven membrane pushbuttons. Pushbuttons are colorcoded (red, white, blue, yellow) by their function to beoperational friendly. For example, blue pushbuttons areassociated with actual program functions, yellow push-buttons with integral testing functions, and white push-buttons are common to both operations or are indepen-dent. White pushbuttons accomplish their function whendepressed. They can be held down and not released toaccelerate their function. Blue and Yellow pushbuttonsaccomplish their function after having been pressed andreleased.

Reset Pushbutton (Red)The Reset pushbutton is used to reset any of the follow-ing: the trip relays (overcurrent and instantaneous), thetrip alarm relay, the trip LEDs, and the ampere demand

current. Reset applies to both normal operations andintegral testing. If the unit is in the auto-reset mode, asset by DIP switch #9 on the back of the unit, the triprelays and the trip alarm relay will automatically resetwhen the circuit breaker is opened after a trip.

Program Mode Pushbutton (Blue)The Program Mode pushbutton, which is accessed byopening the sealable, hinged access cover, is used toenter and exit the program mode. When this pushbuttonis pressed and released, the program LED flashes andsetpoints can be altered. DIP Switch S2 establisheswhen the Program Mode can be entered. With S2 set to“off,” the Program Mode can only be entered when thebreaker is open. With S2 set to “on,” the Program Modecan be entered with the breaker open or closed. Anyselections made in the program mode are only savedwhen the Save Settings pushbutton, which is describedlater, is depressed. When programming is concluded,the Program Mode pushbutton should be pressed to exitthe program mode. Note that if the Save Settings push-button is not depressed prior to exiting the programmode, the previous settings will be retained. The pro-gram mode is also exited if the Reset pushbutton ispressed or if there is no programming activity forapproximately 2-1/2 minutes.

Note: Each Digitrip 3000 is shipped from the factorywith nominal protection settings. The relayshould be programmed by the user before beingput into service, as these nominal values maynot give optimum system protection or coordina-tion. Remove tag from security door to accessthe “Program Mode” pushbutton.

Test Mode Pushbutton (Yellow)Also located behind the sealable hinged access cover isthe Test Mode pushbutton. This pushbutton is used toenter and exit the test mode. When the pushbutton ispressed and released, the word TEST will appear in theSettings/Test Time/Trip Cause display window. If thereis more than 0.1 times (In) current flowing in either thephase or the ground circuit, the Test Mode cannot beinitiated and the error message “ERR” will appear in thedisplay window. The test mode will also automatically beexited if there is no activity for 2-1/2 minutes.

Select Test Pushbutton (Yellow)The Select Test pushbutton is used, after the test modehas been entered, to select the type of test. There arephase and ground tests to trip or not trip the breaker.(See Section 3-3.4).

Test Pushbutton (Yellow)The selected test operation is initiated by pressing andreleasing the Test pushbutton.

NOTICE

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Figure 2-1 Typical Communications Wiring Diagram

➀ FOR NETWORK INTERCONNECTION CABLE, SEE CABLE SPECIFICATIONS ON FIG. 3-1.

➁ REFER TO CIRCUIT BREAKER WIRING DIAGRAMS FOR ACTUAL CONNECTIONS.

➂ CARBON COMPOSITION RESISTOR MUST BE INSTALLED ON THE MOST REMOTE DEVICE AS SHOWN: - 150 OHM, 1/2 WATT FOR 1200 BAUD RATE COMMUNICATIONS.- 100 OHM, 1/2 WATT FOR 9600 BAUD RATE COMMUNICATIONS.

➃ A CUTLER-HAMMER CONI (COMPUTER OPERATED NETWORK INTERFACE) OR CONI-3 CARD MUST BE INSERTEDINTO THE COMPUTER ISA BUS.

➄ CUSTOMER TO SUPPLY A COMPUTER AND MODULAR TELEPHONE CONNECTOR TYPE RJ11 AND WIRE PER VIEW A

➅ GROUND SHIELDING AT ONE PLACE ONLY (COMPUTER END RECOMMENDED).

➆ WHERE DEVICES ARE DAISY CHAINED, TIE SHIELDING TOGETHER FOR END-TO-END CONTINUITY. SOME PROD-UCTS WILL PROVIDE AN EXTRA TERMINAL FOR A TIE POINT FOR THE CABLE SHIELD LEADS.

➇ CIRCUIT BREAKER TRUCK OPERATED CELL TOC SWITCH (SHOWN FOR CIRCUIT BREAKER IN “CONNECTED” POSITION) IS OPTIONAL TO AUTOMATICALLY DISCONNECT RELAY FROM THE COMMUNICATION NETWORK WHENCIRCUIT BREAKER IS IN THE “TEST” POSITION.

➈ ON LAST DEVICE IN NETWORK, TIE BACK SHIELD AND TAPE.

➉ WHEN TOC SWITCH IS USED, DOWNLOADING OF PROTECTION SETTINGS FROM THE COMPUTER WILL NOT BE POSSIBLE WITH BREAKER IN THE “TEST” POSITION.

0 3 1

1

2

TB2

INCOM

Digitrip 3000

0

1

With Digitrip RMS 800

DSII CircuitBreaker0 4 7

IQ DP-4000with PONI 0

IBM (or IBM CompatibleComputer)

A3 A2 A1

RES

0

2

With Digitrip RMS 800

SPB CircuitBreaker

0

P3

3

108 1

52 TOCA

7

852 TOCA

852 TOCA

7

2 2

7

6

4

See View "A"

1234

View "A"

Note: Address Viewed on "SETTINGS" Display Window

9

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Select Settings Pushbutton (Blue)In the program mode of operation, the Select Settingspushbutton is used to step to the next setpoint by press-ing and releasing the pushbutton. This pushbutton stepsforward. To step back, the Select Settings pushbuttoncan be pressed and held, while pressing and releasingthe Lower pushbutton.

Raise/Lower Pushbutton (White)The Raise and Lower pushbuttons are used during theprogram and test modes to increase or decrease thevalue of the displayed setpoint. The Lower pushbuttonalso serves a dual function in conjunction with theSelect Settings pushbutton, as described under SelectSettings Pushbutton.

Save Settings Pushbutton (Blue)While in the program mode, selected setpoints can besaved by depressing and releasing the Save Settingspushbutton. Settings can be saved individually or onetime as a group. If the Save Settings pushbutton is notused, the previous setpoints will remain when the pro-gram mode is exited.

View Settings Pushbutton (Blue)The View Settings pushbutton is functional only whenthe unit is in the normal operating mode, not the pro-gram or test modes. It functions to display the unit’s set-points, including the phase and ground current trans-former ratio selected via programming.

Select Pushbutton (White)The Select pushbutton is used to step between any ofthe eight current values that are displayed in the RMSAmperes window. The eight currents are IA, IB, IC, IG,IA ampere demand, IB ampere demand, IC amperedemand, and IG ampere demand. Stepping with thispushbutton is in the sequence just given. The currentsdisplayed are the present RMS values; the amperedemand currents are the averaged RMS values sensedover a 5 minute period of time. The demand value is thelargest 5 minute average measured since the ampdemand was last reset.

LEDs: LEDs are used to indicate a number of func-tions, operations and/or warnings. Many of the LEDsused provide different indication messages. The specificmessage is determined by the color and a constant onor blinking operation. Several of the LEDs are bi-coloredand can be lit green or red.

Operational LEDThe Operational LED at the top of the relay should begreen and blink on for approximately one second andthen off for one second. This indicates that the relay is

functioning properly in its normal operation mode. If thisLED is blinking red, it indicates the relay may needreprogramming. If this LED is lit in any color shade otherthan a definite green or red, or if it is not blinking at all,an internal problem has been detected requiringreplacement of the relay.

High Load LEDThe High Load LED will blink green when high load set-tings are being selected in the program mode. In theoperational or test modes, the High Load LED will blinkred when a load current of 85% or above the inversetime overcurrent phase pick-up setting is reached. If theload current remains at 85% or above the inverse timeovercurrent phase pickup setting for the time intervalsetting, the LED will change to steady red at the end ofthe time interval. Whenever the load current dropsbelow the 85% level, the timer will reset and the LEDwill turn off.

Communication Trip LEDThis LED, will be continuous red when the breaker hasbeen tripped by the master computer via INCOM. TheLED will turn off when the Reset pushbutton is pressedor the circuit breaker is reclosed.

Curve Shape LEDThis LED will blink green when the slope setpoint is dis-played in the Settings/Test Time/Trip Cause windowwhile in the program mode. When the curve shape set-point is being viewed in the unit’s normal operatingmode, this LED will be a continuous green.

Time Overcurrent Setting LEDThis LED is bi-colored. While in the program mode, theLED will blink green when the inverse time overcurrentpickup setpoint is displayed in the Settings/TestTime/Trip Cause window. It will be a continuous greenwhen the inverse time overcurrent pickup setpoint isbeing viewed in the unit’s normal operating mode. TheLED will blink red whenever the load current exceeds theinverse time overcurrent pickup setpoint. If the relay tripson inverse time overcurrent, the LED will be continuousred.

Inverse Time Overcurrent Time LEDThis LED will blink green when the LED time overcur-rent time setpoint is displayed in the Settings/TestTime/Trip Cause window while in the program mode.When the time multiplier is being viewed in the unit’snormal operating mode, the LED is continuous green.

Short Delay Setting LEDThis LED is bi-colored and operates like the time over-current setting LED.

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Short Delay Time LEDThe short delay time LED, when lit is green, and oper-ates like the inverse time overcurrent time LED.

Instantaneous LEDThis LED is bi-colored and operates like the inversetime overcurrent setting LED.

Phase LEDThe phase LED is bi-colored. The LED will blink greenwhen the phase inverse time overcurrent setting, inversetime multiplier, short delay setting, short delay time, andinstantaneous setpoints are displayed in the Settings/TestTime/Trip Cause window while in the program mode.When these setpoints are viewed in the normal operatingmode, this LED will be continuous green.

The LED will blink red, along with the time overcurrentsetting LED whenever the phase load current exceedsthe inverse time overcurrent pickup setpoint.

The LED will be continuous red, whenever a trip is initi-ated by the phase inverse time overcurrent, short delay,or instantaneous protective functions.

Ground LEDThe ground LED is also bi-colored (green/red). Theground LED operates exactly like the phase LED for allground associated functions.

Amp Demand LEDThis LED will be continuous green when an amperedemand current is being viewed in the RMS Ampereswindow.

IA, IB, IC, IG LEDsThe specific phase or ground current LEDs will be con-tinuous green when that phase or ground current isbeing displayed in the RMS Amperes window. When theAmp Demand LED is also lit, the displayed current is theAmpere Demand Current.

Program LEDThis LED is continuous green when the relay is in theprogram mode.

Test LEDThis LED is continuous green when the relay is in thetest mode.

Display Windows: Two windows are used to display allof the relay’s data, setpoints and messages. One win-dow is located in the upper portion of the relay’s face-plate and is labeled RMS Amperes. A second window islocated in the lower portion of the faceplate adjacent tothe program and test LEDs. It is labeled Settings/TestTime/Trip Cause.

RMS Amperes WindowThis window has a five digit numeric display. It is usedto show:

1. Present phase or ground currents 2. Largest phase or ground demand currents since last

reset3. Fault current (displayed after a trip until a reset action

is initiated)4. Phase and ground current transformer CT setting

(when “View Settings” pushbutton is used with therelay in the normal operating mode)

Settings/Test Time/Trip Cause WindowThis window is a four character Trip Cause Windowalphanumeric display used to show the value of the set-points, the test time, or the cause of trip.

2-2.2 REAR ACCESS PANEL

THE BACK OF DIGITRIP 3000, WHEN ENERGIZED,OFFERS EXPOSURE TO LIVE PARTS WHERE THEHAZARD OF A FATAL ELECTRIC SHOCK IS PRE-SENT. ALWAYS DISCONNECT SOURCE AND CON-TROL POWER SUPPLY BEFORE TOUCHING ANY-THING ON THE REAR OF THE DIGITRIP 3000. FAIL-URE TO DO SO COULD RESULT IN INJURY ORDEATH.

The rear access panel of Digitrip 3000 is normally accessi-ble from the rear of an open panel door (Figure 1-2). Allwiring connections to the Digitrip 3000 Protective Relayare made at the chassis’ rear. For the sake of uniformidentification, the frame of reference when discussing therear access panel is facing the back of the relay. The DIPswitches, for example, are located on the upper left of therear panel (Figure 1-4). Become familiar with the functionsand connections involved, especially the following:

DIP Switches: A set of ten DIP switches are located inthe upper left portion of the rear panel. Refer to Table5.1 for DIP switch positions. Their basic functions are asfollows:

1. Switch S1 is used to select whether the IMPACCbuffers are set for the Digitrip 3000 configuration orthe Digitrip MV configuration. (Refer to Section 5 forconfiguring the Digitrip 3000 as a replacement for aDigitrip MV.)

! WARNING

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2. Switch S2 is used to enable/disable the ability to pro-gram the setpoints when the breaker is in the open orclosed position.

CARE MUST BE TAKEN WHEN PROGRAMMINGTHE DIGITRIP 3000 WHILE THE BREAKER ISCLOSED AND CURRENT IS FLOWING. AN INCOR-RECT SETTING CONFIGURATION COULD CAUSETHE RELAY TO TRIP THE BREAKER WHEN SET-TINGS ARE SAVED.

3. Switch S3 is used to configure the trip contacts asshown below:

Trip Contacts Dip Sw. OFF Pos. Dip Sw. ON Pos.TB 12 & 13 Phase & Ground Trip Inst. Ground Trip Inst./OC

TB 14 & 15 Phase & Ground Trip OC/ Phase Trip Inst./OC/Communications Communications

4. Switch S4 is used to enable/disable the ability toopen or close the breaker remotely from the commu-nications interface (host computer).

5. Switch S8 is used to enable/disable the ability todownload setpoints from the communication interface(host computer).

6. Switch S9 is used to select whether the relay shouldbe self-reset or manually reset (lock out function).For additional details refer to the following para-graphs entitled “Manual Reset” and “Auto Reset.”

7. Switches S5, S6, S7 and S10 are reserved.

Manual Reset: (DIP Switch S9 OFF) In this mode theTrip Instantaneous contact (TB2 12 and 13), TripOvercurrent contact (TB2 14 and 15) and the Trip Alarmcontact (TB2 6, 7 and 8) change state after a protectiontrip operation. The contacts stay in that state until the“Reset” Pushbutton is depressed. In addition, the frontpanel will hold the cause of trip in the “Trip Cause” win-dow and the fault current magnitude in the “RMSAmpere” window until the “Reset” pushbutton isdepressed. A RESET COMMAND can be sent to theDigitrip 3000 by a master computer to remotely reset theDigitrip 3000.

Auto Reset: (DIP Switch S9 ON) In this mode the TripInstantaneous contacts (TB2 12 and 13) or TripOvercurrent contacts (TB2 14 and 15) are momentarilyclosed after a protection trip operation. The contacts willremain closed until the breaker’s 52b auxiliary switchcontact closes. The Trip Alarm Relay, however, remains

energized until the “Reset” Pushbutton is depressed ora RESET COMMAND is received from a communicationsystem master. In this mode after a trip is initiated andthe breaker has opened, the display will BLINK thecause of the trip in the “Trip Cause” window and the“RMS Ampere” window will show the fault current mag-nitude. Both displays clear when the circuit breaker isreclosed.

Communicating LED: A red LED just above terminalblock (TB2) is used when the relay is communicating. Ifthe relay is the type designed to accept field installationof a communication module at a later date, this LED isnot functional at any time.

Terminal Block One (TB1): TB1 is located on the leftside of the rear panel, and is numbered 1 through 15,with 1, 2, 3, 7 and 8 not used.

Terminals 5 and 6 are provided for the AC or DC inputcontrol power connections and Terminal 4 is the con-nection for equipment ground.

Terminal 9 and 10 provide for connection to a requireddry 52b contact and to a 52 TOC contact from the circuitbreaker.

When the relay has input control power, Terminals 9and 10 will have this potential on them.

Terminals 11 and 12 are used for ground zone interlock-ing, inverse time overcurrent protection and short delayprotection. The zone interlocking function is a low levelDC signal used to coordinate with “downstream” and “up-stream” breakers that see or do not see the fault. If thefunction is not used but a inverse time overcurrent orshort delay time is desired, the two terminals should stayjumpered as they were when shipped from the factory.

Terminals 13 and 14 are used for phase zone interlock-ing, inverse time overcurrent protection and short delayprotection.

Terminal 15 is the zone signal common. Zone commonshould never be connected to earth ground.

Refer to Figure 4-1 for a typical phase zone interlock-ing/wiring scheme.

Note: Digitrip 3000 Protective Relays are shipped witha phase zone interlocking jumper (across termi-nals TB1-13 and 14) and a ground zone inter-locking jumper (across terminals TB1-11 and

! CAUTION

NOTICE

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12). For phase or ground zone capability, therespective jumpers must be removed.

Terminal Block Two (TB2): TB2 is located on the rightside of the rear panel and is numbered 1 through 15.Terminals 1 and 2 are used for the internal INCOM com-munications interface. Terminal 3 can be used for anINCOM shield tie point. It is not connected to ground orany electrical circuit in the Digitrip 3000. Terminals 4 and5 are a N.O. contact from an output relay and are wiredin to the circuit breaker close circuit, if a communicationinterface is present and it is desired to be able to closethe circuit breaker from the remote master computer.

Terminals 6, 7 and 8 are Form “C” contacts on the tripalarm relay and change state whenever any protectivetrip is initiated by the relay. They do not change statewhen the master computer initiates an opening of the cir-cuit breaker via the communication interface. After a pro-tective trip, the contacts remain in the changed state untilthe “Reset” Pushbutton is depressed, whether the relay isin the Manual Reset Mode or the Auto Reset Mode. Foradditional details about Manual and Auto Reset Modes,refer to specific paragraphs earlier in this section.

Terminals 9, 10 and 11 are Form “C” contacts on theprotection off alarm relay. The contacts change statewhen nominal control power is applied to the relay andno internal errors are detected.

Terminals 12 and 13 are a “NO” configurable contact.DIP Switch S3 is used to configure the trip contacts.With DIP Switch S3 in the “on” position, this contactcloses when the relay detects a need for the circuit

2-3 UL TESTING AND SPECIFICATION SUMMARY (CONTINUED NEXT PAGE)

ADDITIONAL TESTS (UL REQUIRED):■ Hot and Cold Calibration of Phase Elements■ Meter Readout Accuracy■ Zone Interlocking Functionality

EMC TESTS:■ IEC 255-22-2, Electrostatic Discharge Test (ESD), Rating of 8kV■ IEC 255-22-3 (ENV50140), Radiated RF Immunity■ ENV 50141, Conducted RF Immunity■ CISPR 11 Class A■ CFR 47 FCC Part 15 Subpart b Class A

ANSI C37.90 (TOTAL COMPLIANCE):(UL Required)

■ Make and Carry Ratings Sec. 6.7■ Temperature Test Sec. 7■ Dielectric Test Sec. 8■ Surge Withstand Test Sec. 9

UL 1053 (UL REQUIRED):■ Current Withstand Test Sec. 27■ Control Power Test Sec. 18■ Output Test Sec. 19■ Temperature Test Sec. 20■ Calibration of Ground Element Sec. 21■ Overvoltage Sec. 22■ Overload Sec. 23■ Endurance – Verify with Calibration Tests Sec. 24■ Dielectric Voltage Withstand Test Sec. 25

breaker to trip due to either a phase or ground instanta-neous fault or the discriminator function. With DIPSwitch S3 in the “off” position, this contact closes whenthe relay detects a need for the circuit breaker to tripdue to any type of ground fault.

Terminals 14 and 15 are also a “NO” configurable con-tact. With DIP Switch S3 in the “on” position, this contactcloses when the relay detects a need for the circuitbreaker to trip due to an inverse time overcurrent orshort time function. The contact also operates when thecommunication interface initiates an action to open thecircuit breaker. With DIP Switch S3 in the “off” position,this contact closes when the relay detects a need for thecircuit breaker to trip due to any type of phase fault orcommunications.

Rear Surface Terminals: The rear surface terminals,identified as (A1, A2), (B1, B2), (C1, C2) and (G1, G2)provide the current transformer input connection pointsand are rated for 5 ampere inputs. (A1, A2), (B1, B2)and (C1, C2) are phase A,B,C current inputs respective-ly, while (G1, G2) is the ground current input.

2-2.3 EXTERNAL HARDWARE

The Digitrip 3000 Protective Relay requires that a cus-tomer supplied source of input control power be wiredinto the TB1 terminal block located on the rear panel.Refer to the typical wiring diagram in Figure 3-1. Apower supply can be either AC or DC voltage within theacceptable voltage ranges outlined in Paragraph 2-3entitled “UL Testing and Specification Summary.”

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CURRENT INPUTS:■ CT’s: 5 Amp Secondary■ CT Burden:

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SECTION 3: OPERATION

3-1 INTRODUCTION

This section specifically describes the operation andfunctional use of the Digitrip 3000 Protective Relay. Itdoes not address in detail rear power connections andDIP switch settings. These topics are covered in SEC-TION 5 entitled “INSTALLATION/TESTING/STARTUP.”It would be helpful, however, to become familiar with therelay’s wiring diagram before proceeding with the rest ofthis section (Figure 3-1).

3-2 POWER-UP AND SELF TESTING

When the proper AC or DC control voltage is applied toterminals 5 and 6 of TB1, the unit will initiate a “PowerOn Reset” to its chip circuitry. This causes the unit’sfirmware to perform some self-testing and initializationof its ROM, RAM and E2 (non-volatile) memory. If anyproblem exists, a diagnostic message will be displayedin the Settings/Test Time/Trip Cause Window. A com-plete list of messages and their meanings are given inTable 3.2. Additionally, if a problem does exist, the“Operational LED” will light red and the “Protection OffAlarm” relay will not energize. When all self checks aregood, the “Protection Off Alarm” relay will energize, andthe “Operational LED” will blink green.

3-3 PANEL OPERATIONS

Begin by reviewing the material presented in SECTION2 entitled “FUNCTIONAL DESCRIPTION.” Since basicdefinitions and explanations were given in SECTION 2,no further explanation as to function will be offered inthis section. It is assumed that the operator is now famil-iar with Digitrip 3000 terms, available settings and over-all capabilities.

3-3.1 CHARACTERISTIC CURVE

Digitrip 3000 Protective Relays provide circuit breakerswith an extensive degree of selective coordination poten-tial and permit curve shaping over a wide range. Availablepickup settings, inverse time overcurrent time multipliersettings and inverse time overcurrent (phase and ground)curve selections are addressed here with respect to theireffect on the resultant characteristic curve. In general,there are three different families of curves to choose fromas shown in Table 3.1. These curves were discussedbriefly in Sections 1 and 2. The operating characteristicsof the relay are graphically represented by time-currentcharacteristic curves shown in Figure 3-2.

As shown in Figure 3-2, the ANSI and IEC “CurveShapes” are in terms of multiples of Ipu (PickupCurrent of the CT Primary), whereas “short delay”and “instantaneous” are in terms of multiples of In(5A secondary of CT primary current). The thermalcurve is represented in terms of multiples of In for itscurve shape, short delay, and instantaneous set-tings. This must be considered in the coordinationstudy and in the programming of the Digitrip 3000Protective Relay.

The ANSI curves are defined by ANSI C37.112 and IECcurves are defined by IEC 255-3. These curve shapescombine with the customized capability of the shortdelay and instantaneous functions to allow for very ver-satile coordinated protection schemes. The thermalcurve shape is also customized by the user to anydesired type of coordinated protection scheme.

These curves show how and when a particular relay willact for given values of time and current. The more ver-satile the relay, the easier it is to accomplish close coor-dination and achieve optimum protection. Since theDigitrip 3000 Protective Relay is very versatile, themakeup of a typical curve is presented for clarificationpurposes.

For the sake of simplification, the curve discussion willcenter around a single line curve. Keep in mind, however,that a characteristic curve in reality is represented by aband of minimum and maximum values, not a line (Figure3-3). Minimum and maximum values are generally theresult of tolerances introduced by the manufacturingprocess for components and the relay’s accuracy. Anyexpected value of tripping current or time could be thenominal value anticipated within the plus or minus toler-ance. The tolerances just mentioned are usually stated interms of the relay’s accuracy and frequently highlightedon the actual working curves. Accuracy is stated in terms

Thermal ANSI Curves IEC CurvesCurves (Per ANSI C37.112) (Per IEC 255-3)

It Moderately Inverse IEC-A

I2t Very Inverse IEC-B

I4t Extremely Inverse IEC-C

FLAT IEC-D

Table 3.1 Digitrip 3000 Curve Shapes

NOTICE

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Figure 3-1 Digitrip 3000 Typical Wiring Diagram

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of a plus or minus percentage and represents a permittedfluctuation on either side of the nominal tripping point fora family of relays, like the Digitrip 3000.

The adjustability and continuous current of the Digitrip3000 Protective Relay are two factors that contributesignificantly to the great flexibility of the relay.

a) Adjustability: The adjustability of the relay permitsmovement of its characteristic curve or parts of thecurve. This movement can be done in both a horizontaland vertical direction on the time current grid. The actualshape of the curve can be changed along with the curvemovement. This adjustability permits distinct curves tobe established that will better match the electrical pro-tection to the application need (Figures 3-4 through 3-9)Notice that there is no horizontal movement of the ANSIand IEC curve shapes. Only the point at which the relaystarts to time out moves along the curve shape.

b) Nominal Continuous Current: The Digitrip 3000’snominal continuous primary current (In) is established bythe ratio of the selected current transformers. The cur-rent transformer ratio must by set via the initial program-ming of the relay. These settings must agree with thecircuit current transformers to which the relay is con-nected. Therefore, In is established by the current trans-former ratio used and becomes the primary scale factorfor the trip functions and readouts.

Before proceeding with the curve explanation, it shouldbe noted that combining functional capabilities, such as

inverse time overcurrent, short delay and instantaneous,is a coordination activity. The effects of one set of settingson another setting should always be evaluated to deter-mine if the results under all possible circumstances areacceptable. This helps to avoid unexpected operations ornon-operations in the future. Such possibilities are high-lighted at the end of this discussion as a reminder whenestablishing relay characteristic parameters.

Inverse Time Overcurrent ProtectionInverse time overcurrent protection consists of a curveshape pickup setting and an inverse time multiplier set-ting. The inverse time overcurrent function offers elevenpossible curve shape types as previously described(Figure 3-2 and Table 3.1.). When programming therelay, this will be the first choice to make. The curveshape and its effect on the characteristic curve will becovered with the time multiplier explanations.

The pickup setting establishes the current level pickupat which the relay’s inverse time overcurrent trippingfunction begins timing. If, after a predetermined amountof time, the current condition that started the timingprocess still exists, the relay’s trip relay is energized.Pickup settings can be adjusted from 0.20 to 2.20 timesIn. Refer to Tables 2.2 and 2.3 for a complete set ofavailable settings. Figure 3-4 graphically illustrates howthe Inverse Time Overcurrent Pickup portion of the over-all curve can be moved horizontally on the time currentgrid by means of the pick-up settings. The Inverse TimeOvercurrent Pickup is represented by the dotted lines,while the rest of the curve is represented by a solid line.

Figure 3-2 Digitrip 3000 Time-Current Characteristic Curves

TIM

E

CURRENT

I4t

I2t

It

FLAT

(Curve Shape)

(Short Delay)

(Instantaneous)

Multiples of In

TIM

E

(Curve Shape)

(Short Delay)

(Instantaneous

XTRM

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MOD

Multiples of In

CURRENT

Multiples of Ipu

TIM

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IEC-C IEC-B

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(Curve Shape)

(Short Delay)

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CURRENT

Multiples of Ipu Multiples of In

Thermal Curves (4) ANSI Curves (3) IEC Curves (4)

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The Time Multiplier setting is used to select a predeter-mined amount of time a sustained overload conditionwill be carried before the breaker trips. For the ThermalCurves, a value of (3 x In) is the reference point wherethe programmed time multiplier setting is fixed on thecurve. A wide range of time settings are available anddepend upon the curve shape selection. Refer to Tables2.2 and 2.3 for a complete list of available time multipliersettings. As Time Multiplier settings are varied, the TimeMultiplier portion of the overall curve is moved verticallyup or down on the time current grid. This movement isalso independent of the other portions of the curve.Figure 3-5 graphically illustrates the vertical time linemovement with an I2t curve shape selection. Similarmovement occurs for the remaining curve shapes.

Short Time ProtectionShort time (fault) protection responds to short circuitconditions. Similar to the inverse time overcurrent func-tion, the short time function is comprised of a short timecurrent pickup setting and a short delay time setting.The Short Delay pickup setting establishes the currentlevel at which the relay’s short time tripping functionbegins timing. The Short Delay Time setting establishesthe amount of time a short-circuit will be carried before

TIM

E

Minimum Pickup Setting

MULTIPLES OF In

In

Figure 3-4 Typical Inverse Time Overcurrent PickupHorizontal Movement

TIM

E

CURRENT

(Pickup Accuracy)

(Trip Point)

(Timing Accuracy)

Figure 3-3 Sample Electronic Trip Curves

TIM

E

CURRENT

(Trip Point)

Typical Thermal Curve Typical ANSI and IEC Curves

Note: Pickup and Tripping will occur within ±% of any selected trip point.

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the protective relay's trip relay is energized. As is thecase with inverse time overcurrent protection, shortdelay protection also offers a range of settings for bothpickup and time. Refer to Tables 2.2 and 2.3 for avail-able selections.

Two points should be made concerning the availableselections: 1) In Table 2.2 covering Short Delay Pickupsettings, “NONE” is one of the available selections. If“NONE” is selected, the Short Delay function is disabledand there will be no Short Delay protection. Also, if“NONE” is selected, a Short Delay Time selection is notoffered. 2) There is no curve shape selection for theShort Delay Time portion of the curve. A flat responsecurve is automatic.

When a short delay pickup setting other than “NONE” isselected, the Short Delay pickup and the Short DelayTime portions of the overall curve are moved horizontal-ly and vertically in a similar manner to the inverse timeprotection functions. Refer to Figures 3-6 and 3-7 forgraphic illustrations of this movement.

Note that the scope of protection offered by Digitrip3000 is a coordinated effort. This is especially true when

TIM

E

CURRENT

Time Multiplier isrepresented by thedotted portion of the curve.

Figure 3-5 Typical Time Multiplier Adjustment (I2TResponse)

TIM

E

CURRENT

Short Time Pickupis represented by the dotted portion of the curve.

Figure 3-6 Short Delay Setting AdjustmentT

IME

CURRENT

Short Delay Timeis represented bythe dotted portionof the curve.

Figure 3-7 Short Delay Time Adjustment

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a number of protective functions, such as inverse timeovercurrent and short delay protection are combinedinto one cooperative curve. Figure 3-8 shows a typicaltime-current curve which has both inverse time overcur-rent and short delay protection, and an I2T curve shapeselected. Because of the pickup, time and curve shapeselections made for this illustration, a triangle (shadedarea on the illustration) is formed by the intersection ofthe different time and pickup lines. Internally, the Digitrip3000 design looks at this particular curve as if the shad-ed triangular area does not exist. Therefore, in an actualperformance situation, the short delay time functionwould take precedence over that portion of the inversetime overcurrent line forming the one leg of the triangle.This does not create a problem from a protection orcoordination standpoint. In fact, it is recommended oncertain applications to set the minimum time the Digitrip3000 Protective Relay can respond and where it willintersect the inverse time overcurrent curve. If only theShort Delay Time is required, it is recommended thatthe Short Delay setting be set at 11 times (In). It could,however, cause confusion if the combination of protec-tion functions is not viewed as a coordinated activity.For example, an individual might expect a tripping actionbased on a selected low value for Inverse Time Over-current Time Multiplier. The expected tripping action will

not take place at the expected time, if the Short DelayTime selected is in the higher end of time selection pos-sibilities. It should also be noted that this situation issimilar for other curve selections. The only thing thatchanges with different curve selections is the generalshape of the triangle. When the Short Delay Time set-ting is low enough, this situation will not exist. In sum-mary, for a inverse time and short time cooperativecurve, the minimum trip time cannot be less than theshort delay time setting.

Instantaneous ProtectionInstantaneous (short circuit) protection reacts to highlevel fault currents. The instantaneous pickup settingestablishes the current level at which the relay’s instan-taneous trip relay will be energized with no time delayand is the instantaneous setting times (In).

Table 2.2 specifies the possible settings, which are from1 through 25 and “NONE.” If “NONE” is selected, theinstantaneous trip function is disabled and the discrimi-nator option is offered. See paragraph 2-1.4 (PhaseInstantaneous) to review the discriminator option details.

If an Instantaneous Setting other than “NONE” is select-ed, the instantaneous portion of the overall curve can be

TIM

E

CURRENT

Inverse Time Overcurrent

SD Time

Inst.SD Pick-up

Inverse

Figure 3-8 Typical Curve with I2t ShapeT

IME

CURRENT

Instantaneous pickupis represented by thedotted portion of thecurve.

Figure 3-9 Instantaneous Setting Adjustment

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moved independently in a horizontal direction. Figure 3-9 graphically illustrates this horizontal movement.

The instantaneous protection (INST) is designed to pro-vide a minimum 2 cycle total response time. To providethis fast response time the rms current detection leveland display readout may differ somewhat from a truerms ampere value, if a significant percentage harmoniccurrent is present.

Ground Fault ProtectionThe ground fault protection function can be a compositeof the ground: 1) inverse time overcurrent curve shape,pickup, and time, 2) short delay pickup and time, 3) instantaneous pickup. Its curve shape is independentof the phase curve. There are two differences betweenDigitrip 3000 phase and ground functions: 1) Inversetime overcurrent time multiplier values for the groundfunction of the thermal curves are for (1 x In) while thephase is (3 x In). 2) The short delay settings are moresensitive and can be set from (0.1 x In) to (11 x In).Movement of the pickup portion of the curve in a hori-zontal direction and the time portion of the curve in avertical direction is similar to phase inverse time over-current, short delay and instantaneous functions previ-ously described. Therefore, ground fault curve move-ment is not graphically illustrated. Refer to Table 2.3 forthe available ground fault settings. When programmingground fault protection, keep in mind that if “NONE” isselected, the ground fault protection is disabled. Even ifthe ground fault protection is disabled, a detectableground current will still be displayed.

Characteristic Curve RemindersAs previously mentioned, combining protective capabili-ties is a matter of coordination. The effects of one selec-tion should always be evaluated against other selectionsto determine if the overall desired result is obtained. Forthis reason, keep in mind the following Digitrip 3000selection possibilities and relay design features whenprogramming the unit to closely coordinate with systemprotective needs:

1. When “NONE” is selected as a setting, the associat-ed tripping function is disabled.

2. When “NONE” is selected for the Phase InstantaneousSetting, a Phase Discriminator option is offered.

3. The internal design of the Digitrip 3000 ProtectiveRelay is such that the Short Delay Time setting mighttake precedence over the Inverse Time OvercurrentTime. This is graphically illustrated in Figure 3-8.

3-3.2 PROGRAM MODE

DIGITRIP 3000 PROTECTIVE RELAY SETTINGSMUST BE PROGRAMMED BEFORE THE RELAY ISPUT INTO OPERATION. CARE MUST BE TAKENWHEN PROGRAMMING THE DIGITRIP 3000 WHILETHE BREAKER IS CLOSED AND CURRENT ISFLOWING. AN INCORRECT SETTING CONFIGURA-TION COULD CAUSE THE RELAY TO TRIP THEBREAKER WHEN SETTINGS ARE SAVED.

Notes: 1. The Program Mode can be entered with thecircuit breaker open or closed, depending onhow DIP switch S2 is set. Refer to Table 5.1for DIP switch settings. The circuit breakerposition is determined via the normallyclosed breaker “b” contact on terminals 9 and10 of TB1. Refer to the typical wiring diagramin Figure 3-1.

2. The settings that are altered during a pro-gramming session will not be saved until theSave Settings pushbutton is pressed andreleased.

3. If the circuit breaker is closed during a pro-gramming session and DIP Switch S2 is setto “off,” the unit will exit the Program Modewithout saving any new setpoint values andthe message “ERR” will appear in theSettings/Test Time/Trip Cause window.

4. When programming is concluded and newsetpoints sa