m-3420 specification

Industry Leader Since 1969Made in the USA

Generator Protection M‑3420Integrated Protection System® for Generators of All Sizes

PROTECTION

• Microprocessor-based Generator Protection system provides 17 protective relay functions

• Individually programmable input contacts can be programmed to activate any one of eight output contacts

• Local and remote communications capability for both monitoring and control functions

Unit shown with optional M‑3920 Target Module and M‑3931 HMI (Human‑Machine Interface) Module

–2–

M‑3420 Generator Protection Relay

Protective Functions • Overexcitation (V/Hz) protection (24)

• Phase Undervoltage protection (27)

• Sensitive dual-setpoint, reverse power detection suitable for sequential tripping (32)

• Dual-zone, offset-mho loss-of-field protection (40)

• Sensitive negative-sequence overcurrent protection and alarming (46)

• Instantaneous overcurrent (50) protection

• Inadvertent generator energizing protection (50/27)

• Generator breaker failure protection (50BF)

• Neutral inverse time overcurrent (51N)

• Instantaneous overcurrent (50N) protection

• Three-phase inverse time overcurrent (51V)

• Phase overvoltage (59)

• Generator ground fault protection (59N)

• VT fuse-loss detection and blocking (60FL)

• Four-step over/underfrequency protection (81)

• Generator phase differential (87)

• Ground differential (87GD) protection

Standard Features • Eight programmable outputs and six programmable inputs

• Oscillography recording

• 32-target storage

• Metering of all measured parameters

• Two RS-232 and one RS-485 communications ports

• Standard 19" rack-mount design

• Removable printed circuit board and power supply

• Both 50 and 60 Hz models available

• Both 1 and 5 A rated CT inputs available

• Additional trip inputs for externally connected devices

• M-3800A IPScom® Communications Software

• S-3400 IPScom Communications Software for Windows 7 or later

• IRIG-B time synchronization

• Includes Modbus and BECO 2200 protocols

Optional Features • Redundant power supply

• M-3920 Target Module

• M-3931 HMI Module

• M-3801A IPSplot® Oscillograph Analysis Software

• 4-Wire RS-485 Connection

–3–


PROTECTIVE FUNCTIONSDevice Setpoint Number Function Ranges Increment Accuracy†

Volts/Hz

Definite Time Pickup #1, #2 100 to 200% 1% 1%

Time Delay #1, #2 30 to 8160 Cycles 1 Cycle +25 Cycles

Inverse Time Characteristic Curves Inverse Time #1–#4 — —

Pickup 100 to 200% 1% 1%

Time Dial: Curve #1 1 to 100 1 — Time Dial: Curves #2–#4 0 to 9 0.1 —

Reset Rate 1 to 999 Sec. 1 Sec. 3 Cycles or 1% (from threshold of trip)

The percent pickup is based on nominal VT secondary voltage and nominal system frequency settings.

The pickup accuracy stated is only applicable from 10 to 80 Hz, 0 to 180 V, and 100 to 150% V/Hz.

RMS Undervoltage

Pickup #1, #2 5 to 200 V 1 V 0.5 V or 0.5% 0.8 V or 0.75%*

Time Delay #1, #2 1 to 8160 Cycles 1 Cycle +20 Cycles or 1%**

* When both RMS and line‑ground‑to‑line‑line is selected.

**When RMS (total waveform) is selected, timing accuracy is +20 cycles or 1%; when DFT (fundamental RMS) is selected, accuracy is –1 to +3 cycles or 1%.

Directional Power

Pickup #1, #2 –3.000 to +3.000 PU 0.001 PU 0.002 PU or 2%

Time Delay #1, #2 1 to 8160 Cycles 1 Cycle +16 Cycles or 1%

The per‑unit pickup is based on nominal VT secondary voltage and nominal CT secondary current settings.

Loss of Field (dual‑zone offset‑mho characteristic)

Circle Diameter #1, #2 0.1 to 100.0 Ω 0.1 Ω 0.1 Ω or 5%

(0.5 to 500.0 Ω) (0.5 Ω or 5%)

Offset #1, #2 –50.0 to 50.0 Ω 0.1 Ω 0.1 Ω or 5%

(–250.0 to 250.0 Ω) (0.5 Ω or 5%)

Time Delay #1, #2 1 to 8160 Cycles 1 Cycle –1 to +3 Cycles or 1%

Voltage Control 5 to 200 V 1 V 0.5 V or 0.5% (positive sequence)

Directional Element Fixed at –13° — —

Voltage control for each zone can be individually enabled.

†Select the greater of these accuracy values. Values in parentheses apply to 1 A CT secondary rating.

32

3φ

3φ

40

3φ

24

27

3φ

–4–


PROTECTIVE FUNCTIONS (cont.)Device Setpoint Number Function Ranges Increment Accuracy†

Negative Sequence Overcurrent

Definite Time Pickup 3 to 100% 1% 0.5% at 5 A (0.5% at 1 A)

Time Delay 1 to 8160 Cycles 1 Cycle –1 to +3 Cycles

Inverse Time Pickup 3 to 100% 1% 0.5% at 5 A (0.5% at 1 A)

Time Dial Setting (K= I22t) 1 to 95 1 3%

Definite Maximum Time to Trip 600 to 65,500 Cycles 1 Cycle –1 to +3 Cycles or 1%

Reset Time (Linear) 4 minutes (from threshold of trip) — —

Pickup is based on the nominal CT secondary current.

Instantaneous Overcurrent

Pickup 1.0 to 240.0 A 0.1 A 0.1 A or 3%

(0.2 to 48.0 A) (0.02 A or 3%)

Trip Time Response 2 Cycles — 2 Cycles

Instantaneous Overcurrent, Neutral

Pickup 1.0 to 240.0 A 0.1 A ±0.1 A or ±3%

(0.2 to 48.0 A) (±0.02 A or ±3%)

Trip Time Response 2 Cycles — ±2 Cycles

Inadvertent Energizing

Overcurrent Pickup 0.50 to 15.00 A 0.01 A ±0.1 A or ±2%

(0.10 to 3.00 A) (±0.02 A or ±2%)

Undervoltage Pickup 40 to 130 V 1 V ±0.5 V

Pick-up Time Delay 1 to 8160 Cycles 1 Cycle –1 to +3 Cycles or ±1%

Drop-out Time Delay 1 to 8160 Cycles 1 Cycle –1 to +3 Cycles or ±1%

Breaker Failure

Pickup Phase Current 0.10 to 10.00 A 0.01 A ±0.1 A or ±2%

(0.02 to 2.00 A) (±0.02 A or ±2%)

Neutral Current 0.10 to 10.00 A 0.01 A ±0.1 A or ±2%

(0.02 to 2.00 A) (±0.02 A or ±2%)

Time Delay 1 to 8160 Cycles 1 Cycle –1 to +3 Cycles or ±1%

50BF can be initiated from designated output contacts or status inputs.

50N

3φ

50BF

50BF-Ph

50BF-N

50

27

50/273φ

3φ

46

3φ

3φ

50


–5–


PROTECTIVE FUNCTIONS (cont.)Device Setpoint Number Function Ranges Increment Accuracy†

Inverse Time Overcurrent, Neutral

Characteristic Curve Definite Time/Inverse/Very Inverse/Extremely Inverse

Tap Setting 0.5 to 12.00 A 0.01 A — (0.10 to 2.40 A)

Time Dial Setting 0.5 to 11.0 0.1 ±3 Cycles or ±3%

Inverse Time Overcurrent, with Voltage Control or Voltage Restraint

Characteristic Curve Definite Time/Inverse/Very Inverse/Extremely Inverse

Tap Setting 0.5 to 12.00 A 0.01 A — (0.10 to 2.40 A)

Time Dial Setting 0.5 to 11.0 0.1 ±3 Cycles or ±3%

Voltage Control (VC) 5 to 200 V 1 V ±0.5 V or ±0.5% or Voltage Restraint (VR) Linear Restraint — —

RMS Overvoltage

Pickup #1, #2 5 to 200 V 1 V 0.5 V or 0.5% 0.8 V or 0.75%*

Time Delay #1, #2 1 to 8160 Cycles 1 Cycle +20 Cycles or 1%**

Accuracy applies to values below 180 V pickup.

* When both RMS and line‑ground‑to‑line‑line is selected.

**When RMS (total waveform) is selected, timing accuracy is +20 cycles or 1%; when DFT (fundamental RMS) is selected, accuracy is –1 to +3 cycles or 1%.

RMS Overvoltage, Neutral

Pickup #1, #2 5.0 to 200.0 V 0.1 V ±0.5 V or ±0.5%

Time Delay #1, #2 1 to 8160 Cycles 1 Cycle –1 to +3 Cycles or ±1%

VT Fuse‑Loss Detection

A VT fuse-loss condition is detected by using the positive and negative sequence components of the voltages and currents. VT fuse-loss output can be initiated from internally generated logic or from input contacts.

Time Delay 1 to 8160 Cycles 1 Cycle –1 to +3 Cycles or 1%

Frequency

Pickup #1,#2,#3,#4 50.00 to 67.00 Hz 0.01 Hz 0.02 Hz 40.00 to 57.00 Hz*

Time Delay #1,#2,#3,#4 2 to 65,500 Cycles 1 Cycle –2 to +3 Cycles or 1%

The pickup accuracy applies to 60 Hz models at a range of 57 to 63 Hz, and to 50 Hz models at a range of 47 to 53 Hz. Beyond these ranges, the accuracy is 0.1 Hz.

59N

60FL

81

3φ

59

51N

3φ

51V

3φ


–6–


* This range applies to 50 Hz nominal frequency models.PROTECTIVE FUNCTIONS (cont.)Device Setpoint Number Function Ranges Increment Accuracy†

Phase Differential Current

Minimum Pickup 0.20 A to 3.00 A 0.01 A 0.10 A or 5%

(0.04 to 0.60 A) (0.02 A or 5%)

Percent Slope 1 to 100% 1% 2%

Time Delay 1 to 8160 Cycles 1 Cycle –1 to +3 Cycles or 1%

When a time delay of 1 cycle is selected, the response time is less than 11/2 cycles.

Ground (zero sequence) Differential

Pickup 0.2 to 10 A 0.01 ±0.1 or ±5% (0.04 to 2.00 A)††

Time Delay 1 to 8160 Cycles 1 Cycle –1 to +3 Cycles or ±1%

CT Ratio Correction (RC) 0.10 to 7.99 0.01

The 87GD function is provided primarily for low‑impedance grounded generator applications. This function operates as a directional differential. If 3I0 or In is extremely small, the directional element is disabled.

External Functions

Two functions are provided for externally connected devices to trip through the M-3420 to provide ad-ditional logic and target information. Any one or more of the input contacts (INPUT1 through INPUT6) can be programmed to activate designated output contacts after a selected time delay.

Time Delay #1, #2 1 to 8160 Cycles 1 Cycle –1 to +3 Cycles or 1%

Nominal Settings

Nominal Voltage 60 to 140 V 1 V —

Nominal Current 0.50 to 6.00 A 0.01 A —

VT Configuration Line-Line / Line-Ground/Line-Ground to Line-Line*

Seal-In Delay 2 to 8160 Cycles 1 cycle –1 to +3 Cycles or ±1%

* When Line‑Ground to Line‑Line is selected, the relay internally calculates the line‑line voltage from the line‑ground voltages for all voltage‑sensitive functions. This Line‑Ground to Line‑Line selection should only be used for a VT nominal secondary voltage of 69 V (not 120 V).

EXT

87

3φ

87GD3φ


–7–


MeteringThe M-3420 provides metering of voltages (phase, neutral and sequence quantities), currents (phase, neutral and sequence quantities), real power, reactive power, power factor and impedance measurements.

Metering accuracies are:

Voltage: 0.5 V or 0.5%, whichever is greater 0.8 V or 0.75%, whichever is greater (when both RMS and line-ground to line-line are selected)

Current: 5 A rating, 0.1 A or 3%, whichever is greater

1 A rating, 0.02 A or 3%, whichever is greater

Power : 0.01 PU or ±2%, whichever is greater (real and reactive)

Frequency: 0.02 Hz (from 57 to 63 Hz for 60 Hz models; from 47 to 53 Hz for 50 Hz models)

Oscillograph RecorderThe oscillograph recorder provides comprehensive data recording of all monitored waveforms, storing up to 170 cycles of data. The total record length may be configured by the user for 1, 2, 3 or 4 partitions. The sampling rate is 16 times the power system nominal frequency (50 or 60 Hz). When armed, the recorder is triggered either via the designated status inputs, trip outputs, or via serial communications. When armed yet untriggered, the recorder continuously stores waveform data, keeping the most recent data in memory. When triggered, the recorder continues to store data in memory for a user-defined, post-trigger delay period.

Target StorageA total of 32 targets can be stored. The information will include the function(s) operated, the functions picked up, input/output contact status, timer status, time stamp, and phase and neutral currents at the time of trip.

CalculationsCurrent and Voltage RMS Values: Uses discrete Fourier transform (DFT) algorithm on sampled (16 times per cycle) voltage and current signals to extract fundamental frequency phasors for M-3420 calculations. RMS phase voltages for the 59 and 27 functions (when total RMS is selected), and the 24 function are obtained using the time domain approach to obtain accuracy over a wide frequency band. When the RMS option is selected, the magnitude calculation is accurate over a wide frequency range (10 to 80 Hz). When the DFT option is selected, the magnitude calculation is accurate near nominal frequency (50 or 60 Hz).

Power Input OptionsNominal 110/120/230/240 V ac, 50/60 Hz, or nominal 110/125/220/250 V dc. UL/CSA rating 85 V ac to 265 V ac and from 80 V dc to 288 V dc. Burden 20 VA at 120 V ac/125 V dc. Withstands 300 V ac or 300 V dc for 1 second.

Nominal 24/48 V dc, operating range from 18 V dc to 56 V dc. Burden 20 VA at 24 V dc and 20 VA at 48 V dc. Withstands 65 V dc for 1 second.

An optional redundant power supply is available.

Sensing InputsFour Voltage Inputs: Rated nominal voltage of 60 V ac to 140 V ac, 60 Hz/(50 Hz optional). Will withstand 240 V continuous voltage and 360 V for 10 seconds. Source voltages may be line-to-ground or line-to-line connected. Phase sequence ABC/ACB is selectable. Voltage transformer burden less than 0.2 VA at 120 V.

Seven Current Inputs: Rated nominal current (IR) of 5.0 A or 1.0 A (optional), 60 Hz/(50 Hz optional). Will withstand 2IR continuous current and 100IR for 1 second. Current transformer burden is less than 0.5 VA at 5 A (5 A option), or 0.3 VA at 1 A (1 A option).

–8–


Status Input ContactsThe status inputs, INPUT1 through INPUT6, can be programmed to block any of the M-3420 functions, to trigger the oscillograph recorder, or to operate one or more outputs. The status inputs should be dry contacts and are internally connected (wetted) to a 24 V dc power supply. To provide breaker status LED indication on the front panel, the INPUT1 status input contact must be connected to the 52b breaker status contact. The minimum current value to initiate/pickup an Input is >25 mA.

Output ContactsThe eight programmable output contacts (six form ‘a’ and two form ‘c’), the power supply alarm output contact (form ‘b’), and the self-test alarm output contact (form ‘c’) are all rated as per IEEE C37.90 (See Tests and Standards section for details).

Any of the M-3420 functions can be individually programmed to activate any one or more of the eight programmable output contacts.

Target/Status Indicators and ControlsThe RELAY OK LED reveals proper cycling of the microcomputer. The BRKR CLOSED LED will turn on when the breaker is closed (when the 52b contact input is open). The OSC TRIG LED indicates that oscillographic data has been recorded in the unit's memory. The TARGET LED will turn on when any of the relay functions operate. Pressing and releasing the TARGET RESET button resets the target LED if the conditions causing the operation have been removed. Pressing and holding the TARGET RESET button displays the present pickup status of the M-3420 functions. The PS1 and PS2 LEDs will remain on as long as power is applied to the unit and the power supply is operating properly.

CommunicationCommunications ports include rear panel RS-232 and RS-485 ports, a front panel RS-232 port, and an IRIG-B port. The communications protocol implements serial, byte-oriented, asynchronous communication, providing the following functions when used with the Microsoft™ Windows-compatible M-3800A or S-3400 (Windows 7 or later) IPScom® Communications Software package. MODBUS and BECO 2200 protocols are supported, providing:

• Interrogation and modification of setpoints

• Time-stamped trip target information for the 32 most recent events

• Real-time metering of all quantities measured.

• Downloading of recorded oscillographic data (Not available with MODBUS)

IRIG‑BThe M-3420 can accept a modulated IRIG-B time clock synchronization signal through a BNC connector provided at the rear of the unit. The IRIG-B time synchronization information is used to correct the hour, minute, seconds and milliseconds information.

HMI Module (optional)Local access to the M-3420 is provided through an optional M-3931 HMI (Human-Machine Interface) Module, allowing for easy-to-use, menu-driven access to all functions via six buttons and a 2-line by 24 character alphanumeric LCD. Features of the HMI Module include the following:

• User-definable access codes allow three levels of security

• Interrogation and modification of setpoints

• Time-stamped trip target information for the 32 most recent events

• Real-time metering of all quantities measured

–9–


Target Module (optional)An optional M-3920 Target Module provides 24 target and 8 output LEDs. Appropriate target LEDs will light when the corresponding M-3420 function operates. The targets can be reset with the TARGET RESET button. The OUTPUT LEDs indicate the status of the programmable output contacts.

Type Tests and StandardsThe M-3420 Generator Protection relay complies with the following type tests and standards:

Voltage Withstand

Dielectric WithstandIEC 255-5 3,500 V dc for 1 minute applied to each independent circuit to earth 3,500 V dc for 1 minute applied between each independent circuit 1,500 V dc for 1 minute applied to IRIG-B circuit to earth 1,500 V dc for 1 minute applied between IRIG-B to each independent circuit

Impulse VoltageIEC 255-5 5,000 V pk, +/- polarity applied to each independent circuit to earth 5,000 V pk, +/- polarity applied between each independent circuit 1.2 by 50µs, 500 ohms impedance, three surges at 5 second intervals

Insulation ResistanceIEC 255-5 > 40 Megaohms

Electrical Environment

Electrostatic Discharge TestIEC 1000-4-2 Class 4 (8 kV) – point contact discharge

Fast Transient Disturbance TestIEC 1000-4-4 Class 4 (4 kV, 2.5 kHz)

Surge Withstand CapabilityANSI/IEEE 2,500 V pk-pk oscillatory applied to each independent circuit to earthC37.90.1 2,500 V pk-pk applied between each independent circuit 5,000 V pk Fast Transient applied to each independent circuit to earth 5,000 V pk Fast Transient applied between each independent circuit

Radiated SusceptibilityANSI/IEEE 25-1000 Mhz @ 35V/mC37.90.2

Output Contacts RatingsIEEE C37.90 30 A make for 0.2 seconds at 250 Vdc resistiveUL 508 8 A carry at 120 Vac, 50/60 HzCSA C22.2 No. 14 6 A break at 120 Vac, 50/60 Hz 0.1 A break at 125 Vdc 0.1 A break at 120 Vac

–10–


Atmospheric Environment

TemperatureIEC 68-2-1 Cold, –20° C for 96 hours

IEC 68-2-2 Dry Heat, +70° C for 96 hours

IEC 68-2-3 Damp Heat, +40° C @ 93% RH, for 96 hours

Mechanical Environment

VibrationIEC 255-21-1 Vibration response Class 1, 0.5 g Vibration endurance Class 1, 1.0 g

Compliance UL-Listed per 508 – Industrial Control Equipment

CSA-Certified per C22.2 No. 14-95 – Industrial Control Equipment

External ConnectionsM-3420 Generator Protection Relay External Connections are illustrated in Figures 1, 2, and 3 on the following pages.

PhysicalSize: 19.00" wide x 5.21" high x 10.00" deep (48.3 cm x 13.2 cm x 25.4 cm)

Mounting: The unit is a standard 19", semiflush, three-unit high, rack-mount panel design, conforming to ANSI/EIA RS-310C and DIN 41494 Part 5 specifications. Vertical or horizontal panel-mount options are available.

Contact Beckwith Electric for optional GE L-2/Westinghouse FT-41 retrofit panel vertical mounting details.

Environmental: For flat surface mounting on a Type 1 enclosure, rated to 70°C surrounding air ambient.

Approximate Weight: 13 lbs (7.7 kg)

Approximate Shipping Weight: 15 lbs (11.3 kg)

Recommended Storage Parameters

Temperature: 5° C to 40° C

Humidity: Maximum relative humidity 80% for temperatures up to 31° C, decreasing to 31° C linearly to 50% relative humidity at 40° C.

Environment: Storage area to be free of dust, corrosive gases, flammable materials, dew, per-colating water, rain and solar radiation.

See M-3420 Instruction Book, Appendix E, Layup and Storage for additional information.

Patent & WarrantyThe M-3420 Generator Protection Relay is covered by U.S. Patents 5,592,393 and 5,224,011.

The M-3420 Generator Protection Relay is covered by a five year warranty from date of shipment.

Specification subject to change without notice.

–11–


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–12–


50

Utility System

52Unit

52Gen

50BFPh

87

5040 4651V60FL 32

27

81 27 59 24

CT

VT

CT

M-3420

This function provides control forthe function to which it points.

NOTE: Some functions aremutually exclusive; seeInstruction Book for details.

M-3420 TypicalConnection Diagram

VT

59N R

M-3420

87GD 50N50

BFN 51N

R

CT

Low‑Impedance Groundingwith Overcurrent StatorGround Fault Protection

High‑Impedance Grounding

27

Figure 2 One-Line Connection Diagram

–13–


UTILITY SYSTEM

Alternate VT connectionsRequired generator breaker status input (52b). Contact is closedwhen generator breaker is open. Use unit breaker contact if nogenerator breaker present.Output contact pairs designated by user.Alarm output can be grouped to a single alarm at discretion of user.Available control output to supervise other relays for VT Fuse Losscan be designated.Input contact number is designated by user. WARNING: ONLY dry contacts must be connected becausethese contact inputs are internally wetted. Application of externalvoltage on these inputs may result in damage to the units.

M-3420

Two VT Open-DeltaConnection

40 41 38 3942 43

Three VT Wye-WyeConnection

40 41 38 3942 43

1 1

M-3420

10

1152b

M-34202

48 49

46 47

OtherRelays M-3420

50 51

Generator

58 59

56 57

54 55

OtherRelays M-3420

M-3420

52 53

LowImpedanceGrounding

52Gen

45

44

High Impedance Grounding

M-3420

Example of Control / Output Connections

+

-61 11 10

60

16 15

52b 60FL

POWERSUPPLY

SELF-TESTFAILUREALARM

+

-

DC: 24 V 48 V

EXTERNAL INPUTS ALARM OUTPUTS CONTROLOUTPUTS

TRIPALARM

12 13

POWER OKSTATUSALARM

VTFUSELOSS

TRIP

52G

52Ga

2

4

5

TRIP OUTPUT

OSCILLOGRAPHRECORDERINITIATE

BREAKERFAILUREINITIATE

3 3

M-34206

3ORDC: 110 V 125 V 220 V 250 VAC: 110 V 120 V 230 V 240 V

62

63

NOTE: M-3420 current terminal polarity marks ( ) indicate "entering" currentdirection when primary current is "from" the generator. If CT connectionsdiffer from those shown, adjust input terminals.

A B C

A B C

ABC

58

57 56

55 54

OtherRelays

M-3420

59

a b c58

56

55 54

OtherRelays M-3420

a b c

59

57

IC

IB

IA

ALTERNATECONNECTIONS

Figure 3 Three-Line Connection Diagram

–14–


Standard 19" Horizontal Mount Chassis

19.00[48.26]

17.50[44.45]

17.50[44.45]

ACTUAL

5.21[13.23]

ACTUAL

0.40 [1.02] X 0.27[0.68] Slot (4X)

10.20[25.91]

18.31[46.51]

0.35[0.89]

1.48[3.76]

2.25[5.72]

17.68[44.91]

RECOMMENDED CUTOUT WHEN RELAY ISNOT USED AS STANDARD RACK MOUNT

5.28[13.41]

NOTE: Dimensions in brackets are in centimeters.

Figure 4 Mounting Dimensions

–15–


1.97[5.0]

19.00[48.26]

18.30[46.51]

2.25[5.72]

0.28 [0.71]Dia. (4X)

17.68[44.91]

5.59[14.20]Actual

1.67[4.24]

2.25[5.72]

10.20[25.91]

COM 1

TARGETS

OUT 1

OUT 2

OUT 3

OUT 4

OUT 5

OUT 6

OUTPUTSOUT 7

OUT 8

EXIT ENTER

TARGET DIAG

TIME

OSC.TRIG

SYNC

BRKRCLOSED

OKRELAY

TARGETRESET

PS 2 PS 1

17.5[44.45]

ACTUAL

5.65[14.40]

Recommended cutout when relay is not used asstandard rack mount and is panel cut out mounted.

19.00[48.26]

17.50[44.45]

0.35[0.89]

0.03[0.076]

NOTE: Dimensions in brackets are in centimeters.

6.19[15.7]

Figure 5 Vertical Mounting Dimensions

NOTE: Panels for vertical mounting are available. When mounted vertically, the target module will be located at the top and all front-panel text will be horizontally aligned. Consult Beckwith Electric Co. for details.

BECKWITH ELECTRIC CO., INC.6190 - 118th Avenue North • Largo, Florida 33773-3724 U.S.A.

PHONE (727) 544-2326 • FAX (727) [email protected]

www.beckwithelectric.comISO 9001:2008

800-3420-SP-16MC1 10-16© 2001 Beckwith Electric Co.Printed in U.S.A. (07.30.01)

mailto:[email protected]

www.beckwithelectric.com

m-3420 specification

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