BASIC ELECTRICAL ENGINEERINGPrepared by: Durgarao Ella. Electrical Supervisor

Define the terms with their units:

Electromotive force

It is the force which causes to flow the electrons in any closed circuit. The unit of electromotive force is volt.

Volt. It is defined as the p.d across a resistance of one ohm carrying a current of one Ampere.

Potential Difference (voltage)

The potential difference V between two points in a circuit is electrical pressures or voltage required to drive the current between them.

The unit of potential difference is same as of Electromotive force which is Volt.

Current

Flow of Electrons in any conductor is called Current. It is represented by 'I'. The unit of current is Ampere.

Resistance

Resistance may be defined as that property of a substance which opposes the flow of electricity through it.

It is represented by 'R'. The unit of resistance is ohm.

Ohm's Law

In a closed circuit at a constant temperature the current is directly proportional to the voltage inversely proportional to the resistance

Therefore I=V/R; V=IR.; R=V/I

1What are IR, WR, KWH, OLR, MCC, MCB, MCCB, VCB, BOCB and SF6?

IR - Insulation Resistance WR - Winding Resistance KWH - Kilo watt hour OLR - Over load relay MCC - Motor control center MCB - Miniature circuit breaker MCCB - Moulded case circuit breaker VCB - Vacuum circuit breaker BOCB - Bulk oil circuit breaker SF6 - Sulfer- Hexa fluoride

What is the unit of voltage, current, speed, frequency & power

Voltage - Volt Current - Ampere Speed - Revolutions per minute (RPM) Frequency - Hertz Power - Watt

What is Volt Meter?

The voltmeter is used to measure the voltage in the power system in low voltage system the voltage is measured directly and in high voltage system through a potential transformer.

What is Ammeter?

Load current is measured through an ammeter only. In A.C lower ranges are directly can be read through an ammeter kept in series. For larger ranges are the current transformers are used for measuring the current.

What is Energy Meter?

To measure the power consumed by the circuit (any type of feeder) energy meter is used and the unit is in KWH

Where the shunt resistance used

In D.C circuit the current is measured through this shunt resistance.

2What is the Bridge Megger? Where it is used

Bridge Megger is used to measure the lowest value of resistances accurately and it is used to measure the motor winding resistance and transformer winding resistance during preventive maintenance. The winding resistance of the three windings should be equal.

What is use of Clip-on-meter?

The Tong Tester is called in other words as clip on meter. In this we can measure the current flowing in each phase with out breaking the circuit for any unbalance, if is noticed.

What is AVO meter?

A meter is used in electrical circuit to measuring the value of Current, Voltage and Resistance is called AVO meter.

What is BASEEFA?

British approval service for electrical equipment in flammable atmospheres. The recognized Authorities for the certification and approval of electrical equipment in Hazardous areas in the United Kingdom.

What are Fire Alarm Systems? How can detect the fire

Fire Triangle

For the fire above figures illustrates that for avoiding the fire generally two things cannot be controlled in the Petrochemical industry i.e Oxygen and Fuel. Only thing we can control is ignition part of it by keeping the environmental and equipment in safe condition.

Detection of Fire:-Detection of fires is achieved through the following monitors.

Smoke detector Heat detector Gas detector UV detector 3

Containing of Electrical Fire:-

Contain of electrical fire through fire extinguishers like BCF cylinders and Halon Gas.

What is Halon Gas?

Halon Gas is in the chemical name of Bromo Chlro-Dyflromethane. Halon gas is used generally in the electrical operating system for the fire

extinguishers. This is controlled by fire detection panel. The halon gas is generally used (Types are 1211 & 1301) in the Petrochemical industry.

What is UPS? Draw its block diagram.

Uninterrupted Power Supply is very essential for petrochemical/ Processing industries as the computer, which determines the o0ration under all condition, governs all the controls.

UPS have Converter, Inverter, AVR Battery Bank, Static switch and Bypass Switch.

The converter is feeding supply to the inverter. The battery bank connected in between converter and inverter. The static switch have supply on both end i.e Converter supply and AVR supply

(Static switch is nothing – the two SCR is connected in opposite direction) The inverter is always taking the load, the converter fails to feed supply to the

inverter, it will work with the help of battery bank. If the inverter is fails to take the load, the AVR supply will take the load without

power interruption through the static switch. During the maintenance of UPS, changeover the load to standby supply by using

Bypass switch.Figure:-

Regular Supply Standby supply

Converter Inverter

Static switch

Normal switch

Bypass switchBattery Bank

Load4

SAFETY

AVR

What is the classification of hazardous area?

Hazardous area classified as Zone – 0, Zone -1 and Zone – 2.1. Zone -0 an explosive gas – air mixture is present continuously or for long periods

of time2. Zone – 1 an explosive gas – air mixture is present under normal operation3. Zone – 2 and explosives gas – air mixture only present for short periods and is not

likely to occur except under abnormal conditions.

What type of protection is used in hazardous area?

Zone – 0 Ex 's' (specifically certified for used in Zone '0' )1. Zone – 1 Any type of protection suitable for Zone '0' and Ex 'd' , Ex '1', Ex 'p' ,

Ex 'e'2. Zone – 2 any type of protection suitable for Zone '0' and Zone '1' and Ex 'n' or 'n',

Ex '0', Ex 'q', Ex 'm'.

Ex's' (Ex protection type – Special protection)

This applies to items of equipment not entirely covered by and forgoing concepts but one that can clearly be demonstrated to be explosion proof.

Ex'd' (Ex Protection type – Flame proof or Explosion proof)

Equipment that could ignite an explosive atmosphere is housed within a substantial enclosure. This is capable of containing an internal explosion without transmitting that explosion to the surrounding explosive atmosphere.

Ex 'e' (Ex protection type – increased safety)

Increased measures are taken to prevent the generation of arcs, sparks and excessively hot areas in equipment, thus preventing the risk of explosion inside or outside of the enclosure.

Ex 'I' (Ex Protection type – intrinsic Safety)

Power is limited to this equipment in such a way that a spark or a hot surface would not be hot enough to ignite the explosive atmosphere.

Ex 'p' (Ex Protection type – Pressurized or Purged)

Here the concept used is to house the equipment in an enclosure. Which is pressurized or purged by inert gas, thus preventing an explosives atmosphere from reaching the equipment? 5

Ex 'O' (Ex Protection type – Oil immersion)

All equipment is totally immersed in oil, thus preventing an explosive atmosphere from reaching the equipment.

Ex 'Q' (Ex Protection type – Powder filled)

All equipment is totally immersed in powder, thus preventing an explosive atmosphere from reaching the equipment.

Ex 'N' or 'n' (protection type – non sparking and Restricted Breathing)

This gives a level of protection by housing electrical equipment in substantial enclosures that inhibit mechanical damage and give some degree of ingress protection.

Ex ' m' (Ex protection type – Moulded / Encapsulated)

The apparatus is totally encapsulated by a non-porous compound, Electrical connection is flying leads.

What is the definition of EExd IIB T5?

E Ex 'd' II B T5

Certified to Explosion Type of Type of Temperature European Standard Protection Protection Gas Code

What is the temperature classification?

T1 - 450 degree C T3 - 200 degree C T5 - 100 degree C T2 - 300 degree C T4 - 135 degree C T6 - 85 degree C

What is the gas group classification?

Methane – I, Propane – IIA, Ethylene – IIB, Hydrogen, Carbon disulphide and Acetylene – IIC

6Explain IP 54, IP55 and IP65

IP means Ingress Protection of the enclosures for electrical equipment in Accordance with the Electrical Standards. The first digit represents the degree of protection against the ingress of dust-type particles and the second digit represents the degree of protection against the penetration of water.

IP 54 – The first 5 indicate the protection against dust (no harmful deposit) and the second 4 indicate the protection against projections of water from all directions.

IP55 – The second 5 indicate the protection against jets of water from all directions.

IP65 – The first 6 indicate the protection completely against dust.

Explain different insulation classes and the corresponding temperature rise allowed?

Y-90 E-120 F-155 C-180A-105 B-130 H-180

HAZARDOUS AREA CLASSIFICATIONS & FLAME PROOF EQUIPMENTS

What is ingress protection? What do you mean by IP 55?

Ingress protection is classification of degree of protection provided by enclosures. Protection ratings are prefixed internationally agreed by letters IP followed by two digits First digit denotes degrees of protection provided by the enclosure against solid Second digit denotes degree of protection provided by the enclosure with respect

to harmful ingress of liquids.

1 st digit NO. 2 nd digit

No protection 1 No protectionObjects Greater than 50 mm 2 Vertically dripping waterObjects Greater than 12 mm 3 Angled dripping 75'' to 90''Objects Greater than 2.5 mm 4 Sprayed waterObjects Greater than 1.0 mm 5 Splashed waterDust protected 6 Water jetsDust light 7 Heavy seas -- Effects of immersion -- Indefinite immersion

7Explain what is meant by area classifications? How is the classifications done, define

zones and divisions?

Hazardous area i.e. areas where flammable atmosphere is present are classified according to the degree of hazard. Zones and divisions is the measure of likelihood of hazard.

Division 1 Zone 0 (Gases) --- Continues hazard – flammable atmosphere Zone Z (Dusts) --- Flammable atmosphere is likely to be present

(between 10 to 1000 Hrs/year)

Division 2 Zone 2 (Gases) --- Hazard under abnormal conditions Zone Y (Dusts) --- Flammable atmosphere is likely only under abnormal

conditions (between 0.1 to 10 Hrs/year)

What are hazard categories?

Class 1 (Gases & Vapors) Group A Acetylene Group B Hydrogen Group C Ethylene Group D Methane

Class 2 (Dusts) Group E Metal dust Group F Coal dust Group G Grain dust

Class 3 (fibbers) No sub groups What is Exd & Exe?

Exd - Flame proof Exe - Increased safety

What is the temperature classification for hazardous area equipment?

Class Surface Temp.

T1 -- 450 degree C T2 -- 300 degree C T3 -- 200 degree C T4 -- 135 degree C T5 -- 100 degree C T6 -- 85 degree C 8

CABLES

1. How many types of cables? And explain these factors..a) Groping factor…? (b) Derating factor..?

PVC- Polyvinyl ChlorideXLPE- Cross linked polyethyleneMICC- Mineral insulated copper conductorPILC- Paper insulated lead coveredSWA- Steel wire armored

a) Grouping factor:- Generally cables laid in air and ground. When number of cables laid for a plant then it is laid in a trench which will be grouped or laid one after one which is called Grouping of cables. Grouping factor means since the cables are arranged in a row, their current carrying capacity will be reduced which is given below:b) Derating factor:-

4cables touching 0.756 '' '' 0.679 '' '' 0.5412 '' '' 0.51

30cm spacing between cables

4 cables touching 0.79 6 '' '' 0.71 9 '' '' 0.61 12 '' '' 0.57

45cm spacing between cables

4 cables touching 0.816 '' '' 0.749 '' '' 0.6312'' '' 0.6

2. If the current is 15 A what will be the size of the cable?

2.5 mmsquare3. MICC cable is used for what purpose? What material used for this cable?

Used for Fire alarm and lighting circuits without conduits. Magnesium oxide

94. How to check cable fault?

Isolated the cableMegger the cable Trace the cable fault through cable fault locator and cable route through rout locator

If the cable resistance is high use the burning kit.

5. What is PILC, where it is used, why lead cover is used?

PILC:- Paper Insulated Lead Covered cable. It is used for chemical plant and refinery. Lead cover is used to avoid chemical corrosion of cable

6. Why cable glands are used?

Cable glands are used to give mechanical protection of cable against damages of cables during entering in MCC or junction box. It also gives earth continuity of cable armour and equipment body.

7. What is the type of armor you have in single core cable? Why?

AWA – Non Magnetic

8. What are the points of a single core cable to be earthed?

Only at source side.

9. Why is it necessary to seal PICC cable ends?

Impregnated paper insulation over conductor is hygroscopic and will absorb moisture if exposed.

10. What are the factors considered while sizing the cable?

Voltage dropLoad current Ground factors / Grouping of cables S.C.Current.

1011. What cable do you recommend for hazardous area? What is the advantage of

lead cover for the cable?

PVCSWALC or MICC. To protect from contamination due to hydrocarbons and corrosion.

12. What is polarization index?

Polarization index gives the true value of insulation of electrical equipment under tish of 2.5/5 KV megger used to test a equipment. IR value taken after 15 seconds and the 60 seconds gives the true value.

R60/R15 X IR (PI) should be 1.1 or greater.

11MOTORS

1 What is the slip of an induction motor at the time of start?

100%

2 What is the protection against single phasing?

Negative sequence protection.

3 What are the protections normally provided for H.T motor?

Over current (Inst) Thermal O/C Stalling Earth fault Negative Sequence Temperature

4 What is the difference between VCB and motor starter combination?

VCB can make and break in fault condition, contactor cannot. Hence fuses are used

5 What are the possible causes of excessive vibration on a running motor?

Faulty bearing Unbalance on rotorMis alignmentFaulty FoundationRotor bars open

6 What are the units of measurement for vibration and spike energy?

Vibration Velocity – mm/sec. Spike energy – gse.

7 How do you measure sleeve bearing clearance?

Plastic gauge or lead gauge wire to placed between the shaft and bearing and bolt tightened to normal and measure flattened thickness of the gauge.

8 Explain different insulation classes and the corresponding temperature rise allowed?

Y-90 E-120 F-155 C-180A-105 B-130 H-180

129 What is the maximum speed obtained by 3 phase induction motor with normal

state supply?

Frequency F= PN/120

N= 120F = 120x50 =3000rpm P 2

10 What is the advantage of Star delta starter over DOL starter?

Limiting starting current.

11 Why single phase motor is not self starting?

No revolving field.

12 What is thrust bearing, where generally it is used? Where sleeve bearings used?

Thrust Bearing is used for vertical plange mounted motor sin drive end side Sleeve Bearing is used for HT motors in DE and NDE side.

13 YPM of motor

Obtain the work permit Switch off the breaker and lock it Put caution notice in breaker and push button station Switch 'On' the Earth switch Disconnect Fan cover and clean physically Open the Terminal cover Check the Tightness of Terminals Check the Earth connections Insulation resistance and winding resistance to be checked Switch 'Off' the Earth switch Switch 'On' the breaker and start the motor Check the load current Close the permit

14 If the motor is not stopping what will be the problem?

The 'Off' Button "NC" not openThe Contact gets jammed.

1315 What is slip ring induction motor, how to take connection from rotor?

To get high starting Toque, we include external resistance to the Rotor winding. After motor attain full speed Rotor winding one short circuited. By using Slipring, Carbon brushes connections are taken from Rotor winding.

16 What it meant by MURRAY loop test?

Murray loop test:-

For selecting the cables, manufactures gives the voltage drop/A/Mtr. It should be selected according to the size and the necessity of power required. The calculation given in for voltage of cables is for the reference and theory point of it.

17 Draw the power and control circuit for STAR-DELTA starter connected with 3 phase induction motor? And explain brief?

Star –Delta Starter:- If the stator winding is directly connected supply, because it will draw high

current. To reduce this high current (to control starting current0 Star/Delta starter is used.

In start position the stator windings are connected in star. Then voltage on each phase winding will be equal to line voltage i.e. 58% of the line voltage. Due to this reduced voltage the starting current will also reduce 1/3 times the current which would have been taken while starting the motor direct across the line in Delta.

When the motor gains the speed the starter is quickly changed to run position. Thus connecting the stator winding in Delta.

Figure:

1418 Draw and explain these below motor? Also explain which type safety of hand tools will be use when working with these motors?

a) A/C single phase motor. (b) Permanent capacitor motor. (c) Universal motor.

a) A/C Single phase motor

Single phase's induction motors are not self stating. The single winding of single phase motor will not produce a rotating filed by itself and some

arrangement is required to turn the alternating field which is improved into rotating field. By providing a second winding (Auxiliary winding) on the stator and to alter the phase of the current in the second winding. Thus making it similar to a two phase motor. The phase displacement may be obtained by connecting a capacitance in series with the stating winding or shunting one winding by resistance and another by an inductance.

Instead of using inductance or resistance for giving necessary phase displacement in the starting winding a capacitor is used. The connection diagram shown in the fig. This motor has high torque.

Uses: - Lathe, Fan, Blower, Pumps etc.

Figure

b) Permanent capacitor motor

In this type there is no centrifugal switch. The capacitor remains permanently in series in starting and running condition

Use :- Ceiling fan, Table fan and where low torque is required.

Figure:-

15

c) Universal motor

The motor is designed to work on both AC and DC supplyIn the universal motor stator winding is in series with rotor winding. The stator is

built up of laminations instead of a solid piece as in DC series motor. When working on AC the armature and field current have the same direction with respect to each other. Hence the motor works like a ordinary series motor. The speed is above synchronous speed and below the dangerous value while

working on AC. The load speed characteristic is similar to that of a DC series motor.

Uses of Universal motors;- Portable drilling machine, Hand drills, Blowers, Sewing machines etc.

Figure:-

Safety of Hand Tools

Mostly all hand tools are high speed motors & Universal motors. Earthing the machine is more important and the plug and sockets used should have sufficient current rating. The flexible cable used for extension should not be more than 15mts. All equipments should have double insulated winding. The socket supply source should have a ELCB (Earth Leakage Circuit Breaker) 0.03A protection.

19 Draw and explain D.O.L starter diagram?

OLR

Fuse Stop Start Magnetic Coil

Contactor

Control Supply

Remote Stop Remote Start 20 Draw the DOL starter power and control circuit for L.T motor and explain?

C

21 Draw and explain AUTO transformer starter?

17 22 What are the causes for motor is over loaded?

Over load ; b) Short circuit for motor winding ; c) Single phasing ; d) Loose connection of power cable ; e) Bearing problem.

23 How to find the motor speed and write equation?

By '' Tacho meter''.

Equation N= 120F/p

24 What is 1 phase preventer?

In single phasing if one fuse blown out the motor will run in the same condition, Motor will take start.

Single phasing preventer is relay which is used to prevent the equipment from single phasing. If any fuse blown the motor will take higher current. In that case the humming sound will come.

25 What are types of bearings?

a) Ball Bearing b) Roller Bearing c) Bush Bearing d) Taper Roller Bearing e) Sleeve Bearing f) Thrust Bearing

18H.T MOTORS

Motors working with voltage 3.3 KV and above are HT motors. This motor normally used for higher loads as the operating current can be reduced. Normally these motors are star connected. These motors are having some special cooling arrangements like forced air cooling. Condenser type cooling in which water is circulated to cool the temperature inside. Instead of a ball bearing, sleeve bearings are also used. For cooling the bearing, separate oil is used.

The following protection normally used;

Instantaneous over current Settled normally 10 times the rated current. Operates only during short circuit.

Thermal overload relay Set normally at 110% rated operates at motor overload.

Locked rotor or prolonged start protection Set normally at 125% the rated operates when the load got jammed. Set at normal

starting time + 2 secs.

Negative phase sequence Set normally at 25% the rated. Operates when phase unbalance occurs and single

phasing. (One phase failed)

Earth fault Set normally at 20% the rated operates when fault occurs between phase and

earth.

Motor protection relay is having all the above set protection

Motor is provided with the differential relay protection connected between Star side CTs and phase side CTs as shown.

Figure

19

VIBRATION

Vibration of motor is usually the result of troubles such as unbalance of rotor, misalignment, looseness or bad bearings. Vibration is checked by vibration meter

VELOCIY AND DISPLACEMENT

Vibration can be measured in terms of how fast the part moves. This is called the peak velocity and is measured in inches/secs or millimeter/secs. Velocity is a

function of both displacement and frequency; it provides an added sensitivity to high frequency vibrations.

Vibrations can be measured in terms of how far the part moves back and forth. This is called the peak to peak displacement measured in mils. 1mil= 25.4 microns.

BEARINGS (TYPES)

The bearings used in electrical machineries are Ball bearings, Roller bearings, Tapered roller bearings, Thrust bearings, Sleeve bearings, Needle bearings etc. Generally on load side of the machine Roller bearings are used .

D.E - Drive end N.D.E - Non drive end

Definition for bearing no. 6308

6 – Refers deep groove ball bearing 3 – Refers medium weight ( 2- Light weight 4- Heavy weight) 08- 08X5 = 40mm diameter of the shaft

7308 - Angular contact or thrust bearing C3 - Clearance extra for high temperature Z - Shield bearing

BEARINGS MOUNTING AND DISMOUNTING

Remove motor pulley with 3 leg puller if the motor is small and medium size. For large pulley Hydraulic puller may be used

Remove fan cover and fan Remove outer bearing cover on both ends and remove end shields with markings Take out the rotor from stator Now the motor is dismantled totally while assembling reverse the above

procedure.

20 PROTECTION

1 What is the different between measuring CT’s and protection CT’s?

Measuring CT Ratio error is less Saturates at almost 150% of rated current

Protection CT Ratio error –more

Saturates at many times the rated current

2 Explain what is meant by CT 15, 5p 10?

With a connected Burden of 15 VA; it will have a ratio error of 5% or less for values of primary current up to 10 times rated current.

3 Draw and explain the principles of operations of biased percentage differential protection relay?

This relay protects only the zone connected in between the neutral CT and residually connected CT in the phase side i.e.,., it is protecting star winding of transformer. When any unbalance or earth fault occurs after the phase CT there will be unbalanced current in neutral CT as well as residually connected phase CT and both currents nullified at point '0' so there wont be and current follow in the relay and the relay wont operate.

When fault occurs in the winding there will be a current flow in the neutral CT only. The current will operate the 87TG relay.

Figure

4 Will the differential relay respond to through faults, why?

The percentage differential relay employs two restrained coils and an operating coil per phase. The contact closing torque produced by the operating coil is opposed by the restrained coil torque. Therefore during through fault conditions

21 The setting of the relay is increased and relay operation due to spill current is

prevented. During internal faults torque produced by the restrained coil is ineffective and the relay closed its contacts when setting current flows through the operating coil.

The spill current level for the relay to just operate expressed as percentage of the through fault current causing it, is defined as the % bias of the relay.

i.e. % Bias = Spill current for relay operation X 100 Through fault current causing it

5 Draw and explain the principle of restricted earth fault relay?

For the star winding three line current transformers are balanced against current transformer in the reatral connection. An external fault on star side will result incurrent flowing in the line CT of affected phase and a balancing current in neutral CT. the resultant current in the relay is therefore zero. Hence relay will not operate during an internal fault the neutral CT only carries current and results in operation of the relay.

6 Will the restricted earth faulty relay respond to earth faults on both sides of transformer why?

No because scheme does not cover the primary side.

7 What precautions will you take while disconnecting an ammeter from CT why?

You will short CT With the secondary circuit open there is no secondary MMF to oppose that due to

primary current and all the primary MMF acts on the case as a Magnetizing quantity, resulting in High secondary voltage.

Dangerous to insulation of CT connected apparatus and danger to personnel.

8 What is meant by inverse time O/C relay?

It is the relay whose characteristic is such that the time lag is not fixed but varies inversely as the overload i.e. the longer the O/C the lesser the time lag.

Plug setting for current & time setting has to be done. Advantage of inverse tike characteristic is that equipments can be utilized to

the most advantage so that it can safely take heavy over loads for short periods and lesser over loads for longer periods.

22

9 What is relay coordination? What factors are considered in relay coordination?

When number of relays on in service, obtaining the settings to achieve discrimination between there to isolate only the faulty section of the power system network leaving the rest of the system in disturbed is relay coordination.

Factors considered / methods used:- Time grading Current grading Combination of Time & Current grading.

10 What is reverse current protection? why is it required?

Reverse current protection is used to protect parallel incoming feeders at S/S and also generators operating in parallel. This safeguards the system against total interruption of power supply in the event of fault in one of the feeders or one of the generators.

EXPLIAN BRIEF

OVER LOAD RELAY TESTING.

The characteristics of the relay should be selected and set to suit the protection requirement of particular motor as the thermal time constant for the motor can vary wildly(15 minutes to 1 hour) curve A indicates characteristic of motor heating to reach maximum permissible temperature in 15 minutes for moderate overload ( 1.3 times full load currents). The relay will trip according to characteristics B for overload of 200% the relay will trip in less than 4 minutes. Motor can with stand 200% overload for 4 minutes.

PUSH BUTTON STATION

There are installed in the units near each motor for starting and stopping. The control supply for the stations is 110v D.C leading from the respective switch gears or 230V A.C

MEGGER VALUE

The insulation resistance value of the winding of the motor shall be checked periodically during Preventive maintenance

For 3.3 KV motor the IR value shall be checked with 1KV megger For 11 KV motor the IR value shall be checked with 5 KV megger

WINDING RESISTANCE The winding resistance of the motor shall be checked during preventive

maintenance with the bridge. The winding resistance of the three windings should be equal. 23

LOCKED ROTOR CURRENT

Due to mechanical overload in motor locked rotor can sometimes happen and during this time the motor will draw the maximum current equal to the starting current. This is called the locked rotor current.

STARTING TIME

The time taken for a motor from the starting to attain its full speed is called the starting time. It will be generally 4 to 5 seconds for small and medium range motors and 8 to 10 seconds for large motors.

UNDER VOLTAGE CONDITIONS

Under voltage conditions in a motor greatly affect its performance. During this condition the motor speed reduces it will draw more current and this will cause rise in temperature of windings. For protecting the motor from this condition. Under voltage release is provided.

POLARISATION INDEX

Polarization index gives the true value of insulation of electrical equipment under tish of 2.5/5 KV megger used to test an equipment. IR value taken after 15 seconds and the 60 seconds gives the true value.

R60 R15 X IR (PI) should be 1.1 or greater

EFFECT OF VOLTAGE OVER TORQUE

The torque of machine is proportional to the square of the applied voltage. Variation of line voltage will, therefore effect the operation of the machine.

EARTHING

Generally earthing means non current carrying metallic part of electrical equipments should be earthed to avoid danger of human life.

GRID RESISTANCE

Grid resistance means in a industry or building the no. of earth pits joined parallel together to get a minimum earth resistance value and the value should be less than 1.0 ohms acceptable in the industry.

24PIT RESISTANCE

Individual pit resistance can vary according to the solid resistance and the value can be 5 ohms or more than that. But to get a minimum value all the pits should be connected in parallel as grid.

EARTH PITS

Earth pits are generally used by using charcoal, salt and G.I pipe of 3 mtrs in length and 40mm diameter.

Another type of earth pits is plate earth electrode and mesh type electrode with copper or GI strip brought out.

Another type in Gulf generally used are the solid rod of copper driven straightway in to the earth to get minimum value by driving to a depth of max. 6 mtrs.

EARTH MEGGER

For measuring the earth resistance earth megger is used, and the diagram given below how to measure the earth resistance.

SAFE EARTH RESISTANCE

Generally earth resistance of the total grid should be less than 1.0 ohms which is acceptable for safe operation in industries.

ELCB

Earth Leakage Circuit Breaker If any leakage current passes through earth the circuit breaker trips. Normal operating conditions current will be Zero in the core balance CT. if any

leakage occurs in the load side, there will be an unbalanced current between phase and neutral. That current will operate the trip. The CB test button is connected between after the CT and neutral before CT. when test button is pressed current flows from phase to neutral through the resistor that current only lows through phase inside the CT. so this unbalance current fall in the CT will trip the CB immediately.

Figure ;-

25 COORDINATION OF RELAY

If any fault occurs in motor the nearest relay has trip D breaker itself so that it won't affect the other system. Similarly if any fault occurs after A breaker the nearest is A breakers relay. Sp A should trip and other system not affected.

Normally the operating and tripping of breaker time will be around 350 (Msec) milliseconds.

If after A breaker fault occurs A will trip at 350 msec if it fails B will trip at 700 msec. If B also fails C will trip at 1 sec. This is called the co-ordination of Relays

UNDER VOLTAGE RELAY

This relay operates when under voltage occurs in a connected system, nor5mally this relay setting will be 80% of the applied voltage. This relay having two types instantaneous and IDMT (Inverse Definite Minimum Time)

ILDMT relays are all disc type and the setting can be done through plug setting arrangement.

FREEQUENCY

In AC the voltage which completes one cycle of Sine wave form is called frequency and the unit is HERTZ. Hz.

Normally supply source will be 50hz.

POWER FACTOR

When AC voltage used to an inductive load. The current tags the voltage by an angle Cosine of that angle will give pf.

P.F = cos0 Other ways of calculating P.F = KW/KVA=R/Z= Resistance/Impedance

IMPROVING POWER FACTOR

In industries capacitor is used. In major S/Stations synchronous condenser is used. For 110V DC control supply. A transformer 250/84 V AC is used. Reason for that is in AC RMS value=Peak value/root 2 Peak value = 84X1.414 = 118V

26ABOUT TRANSFORMER EXPLAIN

1. POWER TRANSFORMER PARTS

Primary and secondary terminal boxes Transformer tank Primary winding Secondary winding Radiator tubes Conservator Explosion vent Bucholz relay Oil temperature gauge Breather

Oil drain valve Cooling fans

Sample oil collection oil testing BDV

The transformer windings are placed in oil for cooling as well as for insulation. Oil samples to be collected and tested for breakdown voltage as per the recommendation of the manufacture. Generally the transformer oil will be tested once in three years for the BDV. One oil sample collected will be placed in a test kit and tested. It should withstand 30KV for one minute. The sphere gap will be kept at 2.5mm

2. ON AND OFF LOAD TAP CHANGER

To adjust the operating voltage occasionally off load and on load tap chargers are used. Off load tap changer can be operated only when the transformer is isolated from service, the on load tap changer can be operated even in short times or at peak load to obtain the desired output voltage without switching off the transformer from service.

3. VECTOR GROUPS DYN

The primary is connected in Delta and secondary in Star. The star point is connected to neutral. There is phase displacement of plus 30 between the primary and secondary. There is a phase shift of 30 forward. Hence the number 11 refers to hour 11'0' clock.

Figures:-

27 ONAN

Oil Natural. Air Natural cooling:- The oil converts the heat from core winding to the tank and equalizes temperature on natural ventilation. Dissipation of heat is assisted by constructi0on of tank with corrugated surface or by fitting cooling tube to it. This type of transformers most common and can be used in output up to 3000 KVA.

ONAF Oil Natural. Air Forced Cooling:- in this type of cooling the winding is cooled by

air with alternative additional forced air cooling by running the fan fixed at the radiator tubes.

4. PERCENTAGE IMPEDEMCE

6.5% which means the percentage of normal voltage required on primary to cause full load current flow through secondary bei9ng shorted. It refers to the short circuit current. A short circuit on the secondary with full primary voltage the current will be 100/6.5 times the full load current. Hence for an example the percentage impedance of a desalted transformer will be 100% so that even at shorted H.T terminals ( because of water high level) the primary current will not go beyond the full load current and continue to work.

5. OIL AND WINDING ALARM TRIP

The power transformer is provided with dial thermometer for oil temperature range 0-100degress C. alarm contact set at 84.5c on actuation, flag relay falls and initiate Minor trouble winding temperature indicator facilities monitoring and indicating transformer hot spot temperature which initiates alarm and trip circuits.

6. PROTECTIONS OF TRANSFORMER

Buchholz relay (1 st stage) This relay detects the gas evaluation due to internal trouble and gives an alarm,

and is suited to the detection of minor or slowly developing faults.

Buchholz relay (2 nd stage) When a major fault takes place suddenly inside the Transformer. Oil flows

suddenly from the transformer proper to the conservator. The second stage of Buchholz relay is actuated by this oil current.

Pressure relief device When the internal pressure of the Transformer rises above the set value. The

pressure relief device function.

28Differential relay

This relay detects the internal defects by comparing the input current and the output current of the Transformer. If it functions combined with other protection devices. It is indicative, in almost all cases of an internal fault. Note that this relay sometimes functions by the exciting current when the Transformer is made line. And this is of course not attributed to internal defects.

Over current relay, Ground fault relay These are intended for detecting faults in the electric system connected with the

Transformer. A fault in the Transformer results in the function of these relays. This is always accompanied by the actuation of protective devices of the Transformer.

TRANSFORMERS

1 Transformers transformation ratio….is?

Transformer is a static device. Which converts high voltage to low voltage and low voltage to high voltage? But temperatures kept constant (Frequency)

Transformation ratio (K) = V1 = N1 = I2o V2 N2 I1

2 Explain the function of buchhlozs relay for transformer protection?

It is the gas and oil operated relay. It has two circuits, one is trip and second is alarm. Any minor fault develops that time the evaporated gas will actuate the alarm circuit, otherwise any major fault rush of oil will actuate the Trip Circuit.

3 What are the protections for transformers?

Bucholz relay Overheated relay Earth fault relay Temperature sensor

For higher transformer additionally

Restricted Earth fault relay Differential relay

4 How to check transformer oil, what should be value?

To collect oil from bottom drain in test kit Adjust test kit spears (2.5mm or 4mm0 Increase the voltage gradually up to tripping point The oil should with stand 30kv for 1 minute gap with a gap of 2.5mm 29

5 What is the breather, details about the silica gel?

It is a small container, contains silicagel and oil. It absorbs the moisture from, the atmospheric air and allow the fresh air to the conservator

What is C.T and P.T?

CT is a Current Transformer which step down the current. It is used for current measurement and protection.

6 Y.P.M of transformer..?

Obtain the work permit Transfer the load to the other transformer

Switch ''On'' the earth switch on primary and secondary side Physically clean the Transformer Check the insulation resistance of primary and secondary winding and check the

winding resistance Check the terminal tightness Check the earth connections of transformer Carry out BDV test of transformer oil Control box cleaned with contact cleaner Check the silica gel Check the HT and LT bushings Off' the earth switches Energize the transformer and give load Close the permit

7 Which are the conditions for parallel operation of transformers?

Voltage must be same as check tap-changer position Frequency must be same Phase sequence must be same Impedance of both the transformers has to be same Vector group of both must be same

8 What is meant by % impedance voltage?

When impedance voltage is applied across one winding of a transformer it produces normal Fl current to flow through second winding when its terminals are short circuited expressed as % of applied voltage.

309 What is the functions breather?

Accommodate the change in oil level with temperature Traps the moisture while breathing

10 Colour of fresh and used silica gel?

Fresh - Blue Used - Pink

11 Quantities of transformer oil?

High dielectric strength 30 kv with 2.5 mm gap between spheres, moisture content low (2 to 3 mgm JOH/g0). Acidity low, flash pint & pour point, viscosity.

Two transformers feeding a system with bus coupler closed and opened. What are the advantages and disadvantages?

Bus closed :

Better stability & redundancy – advantageFault level increase – disadvantageMore cost of switchgear – disadvantage

Bus open :

Reverse of the above

12 Draw the vector diagram of DY 11 transformer? A2

What are the losses in transformer?

Core loss & Copper loss

3113 Which of loss is kept to the minimum in (a) distribution transformer, (b) power

transformer? Why?

Distribution transformer - Core loss Power transformer - Copper loss

14 What is the approximate value of transformer’s magnetizing in rush current?

The management inrush current of a transformer is in the tune of 16-20 times its rated current.

15 What protections do you recommended for 10 MVA, 11/3.3 KVA transformers?

Over current inst. & delayed Earth fault Differential

Bucholze Temperature

32H V CIRCUIT BREAKERS

1 What are the ratings required to be specified for a HV circuit breaker?

Rated voltageRated insulation levelRated normal currentRated frequencyRated duration of short time currentRated short circuit breaking currentRated short circuit making currentRated peak with stand currentRated TRV (Transit Recovery Voltage for terminal fault)

2 What is meant by short circuit breaking current?

The rated short circuit breaking current of a circuit breaker is the highest value of short circuit current which a circuit breaker is capable of breaking under specified condition of transient recovery voltage and power frequency voltage. Express in KA, RMS at contact separation.

3 What is meant by short circuit making current?

Rated making current=1.8xRoot 2 x rated short circuit breaking current. = 2.5 x rated short circuit breaking current.

4 What is rated short time current (duration of short circuit)?

It is the R.M.S value of current that the circuit breaker can carry in fully closed position during a specified time under prescribed conditions of use and behavior.

Expressed as KA for period of 1 second or 3 seconds.

5 What are the techniques employed to extinguish the arc in AC circuit breaker?

High resistance interruption Low resistance or zero point interruption where are gets extinguished at natural

current zero of AC wave and is prevented from restating again by rapid build up of di-electric strength of contact space.

6 What is anti pump relay?

A feature in corperated in the circuit breaker or reclose scheme where by in the event of a permanent fault repeated operations of the circuit beaker are prevented when the closing impulse is longer than the sum of the protective relay and circuit breaker operating times.

337 How can you ensure vacuums level inside the vacuums bottle?

Vacuum Gauge By judging the pulling force of contact by hand or by spring balance By applying power frequency high voltage test.

8 What are the important checks or OCB’s during maintenance?

Check insulation resistance of each pole phase to phase/phase to groundCheck di electric strength of oil and oil levelCheck mechanical operationsClean insulators Check contact length land simultaneous contacts touch Measure contact resistance

9 What are the types of circuit breakers?

MCB – Miniature Circuit BreakerMCCB – Moulded Case Circuit BreakerOCB – Oil Circuit BreakerMOCB – Minimum Oil Circuit BreakerACB – Air Circuit BreakerVCB – Vacuum Circuit BreakerSF6 – Sulphur Hexa fluoride circuit breaker

10 How do you carry out the yearly preventive maintenance of VCB?

Obtain the permit Transfer the load of breakerSwitch OFF and rack out breakerDischarge spring alreadyPhysically clean the VCBCheck and clean the finger contactCheck the mechanism and apply greaseRack in the breaker in test position Electrically on the breaker three times for trialRack in the breaker in service position and give the loadClose the permit

3411 How do you carry out the maintenance of A.C.B?

Obtain the work permit Transfer the load of breakerRack out the breaker and discharge the spring and already chargedPhysically clean the ACBOpen the Arc check, Check and clean the fixed and moving contactsCheck and clean the finger contactsCheck the mechanism and grease it Rack in the breaker in test positionSwitch ''On'' and ''Off'' the breaker electrically for trialRack in the breaker in service position Energize the breakerClose the permit

12 What maintenance required on oil circuit breaker?

Check all circuit carrying parts and attend to the arcing contactTest the oil and change it if it is badInspect the insulation for possible damageCheck closing and tripping mechanism

35LAMPS

INCANDESCENT LAMP

The lamps consist of an evacuated glass bulb or gas filled having fine metallic wire within it. The filament material normally used is tungsten. Tantrum & carbon also used for filament. The filament should have the following properties.

Melting point should be high. Vapour pressure and temp coefficient should be low Material should be ductile and mechanically strong enough to bear vibration

during use. Tungsten filament lamps have an average life of 1000 hours under normal

condition.

SODIUM VAPOUR LAMP

This type of lamp is of low luminously so the length of this lamp is large. To get the required length it is made in the form of a U tube. Two oxide coated electrodes are sealed in to the ends. The tube contains a little sodium and neon gas. The U tube is enclosed in a double walled vacuum flask to keep the temperature with in working range. Before the lamp starts working sodium is in the form of a solid deposited on the side of tube walls. In the beginning it operates as a low pressure neon lamp with pink colour. The lamp gets warm, sodium is vaporized and it radiates yellow light and after about 10-15 minutes the lamp starts giving full light.

MERCURY VAPOUR LAMP

It consists of a glass tube of borosilicate which is quite hard. At the two ends in the tube are provided with specially coated electrodes. Near the upper electrode is another auxiliary starting electrode which is connected to the bottom electrode through a high resistance. The tube is sealed with an inside pressure of 1.5 atmosphere. This tube is further evolved by another tube the advantage of which is that the heat of inner tube may not be dissipated outside.

The lamp has screwed cap and is connected to the main through choke. To improve the P.F a condenser connected across the mains.

The inner in addition to the mercury, also contains small quantity of argon gas. Since at the time of starting the tube is cold and the mercury is in the condensed form. When the tube is switched on, tube start is glowing between main and auxiliary electrodes and after about five minutes the lamp starts giving the full output.

36

FLUORCENT TUBES

Due to low pressure the lamp is in the form of long tube coated inside with phosphor. The tube contains a small amount of mercury and a small quantity of argon gas. When temperature increases the mercury changes into vapour form which it takes over the conduction of current. At each end of the tube tungsten electrode coated with an electron omitting material.

Figure:-

At the time of switching ON the starter switch is in closed position. Current flows through the choke and starters. The starter switch is open due to heating of its bimetallic strip. The energy stored in the choke is suddenly released in the form of a voltage surge which causes starting of discharge through the tube between electrodes. This discharge is self sustaining and tube continues to glow. The colour of the fluorescent lamp depends on the coating used.

Calcium Tungstate - Blue Magnesium Tungstate - White Blue Cadmium Silicate - Yellow Pink Zinc Silicate - Green

Average life of fluorescent tube is 3000 hours.

HALOGEN LAMP

This type of lamp will be having tungsten filament connected from one end to another end of a lengthy thin glass tube. This glass tube is filled with Halogen Gas.

Halogen is a family of gases. The gas the high temperature and the shape of glass tube do not allow the evaporated gases of the filament to accumulate on the side of the glass. Hence the life of this lamp is high.

37

BATTERIES & CHARGERS

What is the specific gravity value of battery cell? How to measure?

1280 for fully charged lead acid cell 1260 for half charged lead acid cell 1180 for dead cell (lead acid cell) 1200 for fully charged nickel cadmium cell and discharged condition same value.

The specific gravity can be measured by ''Hydrometer''

How to connect the battery in series and parallel?

If the Batteries are connected in Series the voltage will be increase and the Batteries are connected in Parallel the Current will be increase

If one battery cell is dead, how to replace that battery?

One by pass jumper is to be provided across the battery and replace it. After replacing the by pass jumper must be removed.

How to get 24V using 1.5 V cells?

16 number of cells are to be series connected we can get 24V

What are the battery maintenance procedures? Obtain work permit Clean the battery terminals and apply petroleum jelly Check the voltage per cell Check the specific gravity of electrolyte Check the electrolyte level Check the electrolyte temperature Check the total voltage Close the permit.

38 DISTRIBUTION

1 What is ring main and what are the advantages?

In a ring main system each load current is connected to the next in the form of closed ring around the system.

The ring main contains advantages of duplicate mains with less cost. Quick isolation and more flexibility.

2 How can you limit the fault level in a power system?

By inserting current limiting reactor in series with line.

3 In a 11 KV bus if you add a transformer 1000 KVA or add 1000 KVA motor in which case fault level will increase in 11 kv bus and why?

1000 KVA motor because if feeds fault current to 11KV bus during fault conditions due to generator action.

4 Draw the single line diagram of a substation?

5 What are the advantages of neutral grounding?

6 What is the disadvantages of low P.F how can it be improved?

Tariff will more Cable and switchgear size will increase by adding capacitors or by running

synchronous motor over circlet.

39O/H TRANSMISSION

1 What is corona phenomenon? When does it occur?

Corona is a type of electrical discharge at the surface of conductors at high voltage because of voltage stress, it occurs at foul weather, depends on pressure, temperature, humidity, pollution level, in air and condition of conductor surface.

2 What is acceptable corona losses in foul weather?

5KW/KM

3 How does lightning arrestor work?

Lightning arrestors employ some form of non leaner type of resistance like thyrite or matrosil whose resistance decreases rapidly with increases of applied voltage. But as soon as energy has been dissipated resistance is restored to a high value which suppresses the arc across the gap effectively when line voltage returns to normal.

4 What are the points to se checked when carrying out inspection of O/H lines?

Frequency weekly/monthly depending in location Check points non growth of trees, birds nests, cracks of insulators, faulty line

regulation structure for mechanical defect-corrosion.

SAFETY What precautions should take while working with electrical supply?How many types work permits explain?What precautions should take while working with open bus bars?

40

Transformer Protection Relays

MCGG-48/125 ; A-1 ; F=50/60hzMake GEC ALSTHOM

Relay No.s:-

MCGG :- 50/51-Over current relay 51N—Earth fault relay

MMLG01 :- O/C & E/F - GEC ALTHOM

MVAJ :- Trip/Lockout – 86 110/125 volts

MVAA :- Buchholz Trip/Alarm –63/AT

MVAA – :- Winding Temperature -- Trip/Alarm -- 26W A/T Winding Temperature Trip – 26WT Winding Temperature Alarm – 26WA

MVAA :- Oil Temperature Trip/Alarm – 26QA/T

Oil Temperature Trip 26QT Oil Temperature Alarm 26QA

MVAA :- Oil Pressure/Oil level Trip / Alarm 63P/63L Oil pressure trip 63PT Oil pressure alarm 63PA-----------110/125v

SWITCH GEAR –HAWKER SIDDELEY (VMH)VACCUM CIRCUIT BREAKER

HT MOTOR PROTECTION RELAYSM.P.C 2000 D :- 110V/ac-dc--- 1A/50Hz

Protection Relay No.s

46 Reverse phase or phase unbalance current relay48 Incomplete sequence relay49 Thermal relay for rotating machines95 Automatic frequency regulator or frequency relay50N --- Earth Fault Relay26W Thermal relay for stationery apparatus

Motor Protection :-MMLG01 – (GEC-ALSTHOM)TRIP LOCK OUTProtection Relay86:- Over/Under volts ; 100/125 D.C supply SW.GEAR – HAWKER SIDDELEY 41

3.3kv BUS COUPLER PRTECTION RELAYS

o MCGG :- O/C & E/F --51/51N -- 48/125V --1A-- 50/60HZ.

o MMLG01 :- O/C & E/F

o MVAJ :- TRIP/LOCKOUT—86---- 110/125V

o MVTU :- R.H BUS BARS--- UNDER VOLTAGE – 27T—(R-Y) 110/125V

o MVTU :- R.H.BUS BARS--- UNDER VOLTAGE-27T—(Y-B) 110/125V

o MVTU :- R.H BUSBARS--- UNDER VOLTAGE 59R – (R-Y) 100/120V

o MVTU :- R.H BUS BARS—UNDERVOLTAGE 59R – (Y-B) 10/120V

o MVAJ :- L.H BUS BARS—OVER/UNDER VOLT 86 – 110/125 AC/DC

o MVAJ :- R.H NUS BARS—OVER/UNDER VOLTS 86—110/125V— AC/DC

3.3KV INCOMER FEEDER PROTECTION RELAYS

o MCGG :- STAND BY E/F 51G—48/125V –1A—50HZ

o MMLG01 :- STAND BY E/F

o MVAJ :- TRIP / LOCKOUT 86—110/125V

o MMLGO1 :- RES E/F

o KCEG 130 ;- ERECTIONAL O/C ; 50/51/67 – 24/125V DC—1A—50HZ

o MMLG01 :- EITECTIONAL O/C

o MAKE ---GEC ALSTHOM

440 VOLT BUS COUPLER PROTECTION RELAYS WITH ACB

o MVAA :- INTER TRIP – 110/125V

o MVAJ :- LOCK OUT –110/125V

o MVAX :- TRIP CCT SUPERVISION

o MCGG :- OVER CURRENT / EARTTH FAULT 48/125V—1A—50HZ

o MMLG01 :- TEST BLOCK

o MAKE ---- GEC ALSTHOM 42

440V INCOMER FEEDER PROTECTION RELAYS WITH A.C.B

MVAA :- INTER TRIP – 110/125V

MVAJ :- LOCK OUT – 110/125V—AC/DC

MVAX :- TRIP CCT SUPERVISION –110/125V DC—1A—50HZ.

3 PHASE ---45 DEGREE ANGLE

MCAG :- RE.EARTH FAULT RELAY

MCGG :- OVER CURRENT 48/125V DC—11A—50HZ

MCGG :- EARTH FAULT – 48/125V—1A—50/60HZ

MMLG01 :- TEST BLOCK—

MAKE --- GEC ALSTHOM

TEM POWER ACBTERASAK8I CE (AT20)

V= 690V ACF= 50/60 HZI= 2000ASTANDRD—IEC-947-2UTILIZATION CATEGORY-B

Breaking capacity (icu) (with inst) ics=100% icu690v----50KA550-600---50KA220-500V--- 65KA

Short time current (icw) 1sec-50ka---3sec-50ka

Motor 110v acShunt 110v dc

43

SI MOTOR MANAGER – 2

1. Set point 2. Actual values

1.In set point

Communications Drive identification Starter CT inputs Fault mode Statics End of page S1

2.In Actual values

Motor Data

Set point

Communication Address off Communication type – modbus Baud rate – 19200 Restore control mode – Disable

Drive identification Drive name – 27-EM-1503-2 Motor rating – 30kw System supply – 440v

Starter Type – DOL non reversing

CT inputs Phase CT primary amps – 60 Earth fault CT input – 2000:1 – CBCT Nominal frequency – 50hz

Fault mode Internal fault trip – Enable Serial comms failure trip – off

44

Statistics Clear timers – Disable Clear counters – Disable

Actual values

Motor data – 27-EM-1503-2 Status AVIL-AUTO R-0,Y-0,B-0 Fearth current – 0.0A Motor load – 0% full load Thermal capacity – used 0% Phase current inbalnce-0% Acceleration time – 2.4s Last start peak inrush – 290A Time to trip----

45

MOTOR PROTECTION

46/48/49/95/50N/26WMPC-2000

W.M.C.OIL FEED PUMP27-PM-1301-270K.W

1

PRESS

SET PAGE

IN SET PAGE

1. COMMUNICATION SETTINGS2. SYSTEM PARAMETER SETTINGS3. VOLTAGE SETTINGS4. CURRENT SETTINGS5. TEMPARATURE SETTINGS6. TRIPING / ALARM OPTIONS

CHECKING (LINE DOWN-LINE BACK)CHANGE THE VALUES (VALUE / UP-DOWN)

PRESS

DATA PAGE

IN DATA PAGE

1. MEASURE DATA2. CALCULATED DATA3. LOGICAL INPUTS CONTACT STATUS4. STATISTICAL DATA5. FAULT DATA

CHECKING (LINE DOWN-LINE BACK)CHANGE THE VALUE (VALUE / UP-DOWN)

2

SET PAGE

1. COMMUNICATION SETTINGS

1. FAST SCAN ANNUAL- 4222. FAST SCAN ANNUAL-313. FAST SCAN ANNUAL- 20 4. SERIAL LINE NO-335. BAUD RATE- 96006. DRIVER NUMBER- 0

SET PAGE

2. SYSTEM PARA METER SETTINGS

1. LOC/REM DISABLE NO2. PROTECTION ON IT YES3. AUX.2 DELAY (0) SEC4. DESIGNATE AUX.2 TRIP5. AUX.1 DELAY (0) SEC6. DESIGNATE AUX.1.ALARAM

7. STAR TO DELTA AT8. TRANSITION TIME 9. MAX TIME IN STAR10. STARTING METHOD DIRECT ON LINE11. START/STP SIGNAL MOMENTARY12. CURENT INHIBIT 1000% OF FLC13. E/F TRIP DELAY 0.0 SEC14. E/F TRIP 6% OF INOM15. E/F ALARAM DELAY 10 SEC16. E/F ALARAM 3% OF INOM17. EARTH FAULT CT PRIMARYY -100 AMP18. CT PRIMARY-100 AMP19. MOTOR FLC- 55 AMP20. VT SECONDARU- 110V21. VT PRIMARY- 3300 VOLT 22. LINE VOLTAGE- 5700 VOLT

3

SET PAGE

3. VOLTAGE SETTINGS

1. O/V TRIP DELAY 1 SEC2. O/V TRIP 120% OF Vn3. O/V ALARM 115% OF Vn4. RESTART DELAY5. U/V AUTO RESTART NO 6. U/V DELAY 5 SEC7. U/V SETTINGS 70% OF Vn

SET PAGE

4. CURRENT SETINGS

1. UNBALLANCE MAX. TIME-30 SEC2. UNBALANCE CURENT 10% OF FLC3. O/L RESET METHOD HAND4. STALL TIME FACTOR- 50%

5. COOL TIME FACTOR- 56. HOT/COLD RATIO- 60%7. T6x TIME-6 SEC8. THERMAL ALARAM 80% OF CAPACITY9. OVER LOAD SETTING 105% OF FLC10. HIGH SET DELAY 0.0 SEC11. HIGH SET SETTING 800% OF FLC12. LOW SET DELAY 2 SEC13. LOW SET SETTING 400% OF FLC14. LOAD INCREASE AC 120% OF FLC15. U/V TRIP DELAY 5 SEC 16. U/V TRIP 40% OF SEC17. U/C ALARAM DELAY 2 SEC18. U/C ALARM 50% OF FLC19. STAART INGIBITOR 60 MIN 20. START PERIODS 60 MIN21. NUMBER OF STARTS-222. MAX. START TIME. 5 SEC

4

SET PAGE

5. TEMPARATURE SETTINGS

1. CHANNEL 3 TRIP 155*C2. CHANNEL 2 TRIP 155*C3. CHANNEL 1 TRIP 155*C4. CHANNEL 3 ALARAM 145*C5. CHANNEL 2 ALARAM 145*C6. CHANNEL 1 ALARAM 145*C7. TMERMISTOR TYPE8. CH.123 SENSOR RTD

SET PAGE

6. TRIPING / ALARAM OPTIONS

1. EXTERNAL FAULT 3 PLC RESET –ENABLE 2. EXTERNAL FAULT 3 PANEL RST- ENBLE 3. EXTERNAL FAULT 3 AUTO RST- DISABLE4. EXTERNAL FAULT 3 ALARAM DISABLE5. EXTERNAL FAULT 3 TRIP – DISABLE6. EXTERNAL FAULT 2 PLC RESET –ENABLE 7. EXTERNAL FAULT 2 PANEL RST- ENBLE 8. EXTERNAL FAULT 2 AUTO RST- DISABLE9. EXTERNAL FAULT 2 ALARAM DISABLE10. EXTERNAL FAULT 2 TRIP – DISABLE11. WELDED CONTACTOR PLC RESET – ENABLE12. WELDED CONTACTOR PANEL RST – ENABLE13. WELDED CONTACTOR AUTO – DISABLE14. WELDED CONTACTOR ALARAM – DISABLE15. WELDED CONTACTOR TRIP – DISABLE16. CONTACTOR CIRCUIT OPEN PLC RESET – ENABLE17. CONTROL CIRCUIT OPEN PANEL RST – ENABLE18. CONTROL CIRCUIT OPEN AUTO RST – DISABLE19. CONTROL CIRCUIT OPEN ALARAM – DISABLE20. CONTROL CIRCUIT OPEN TRIP – DISABLE 21. EMERGENCY SSTOP PLC RESET – ENBLE22. EMERGENCY STOP PANEL RESET – ENBLE 23. EMERGENCY STOP AUTO RESET – DISBLE24. EMERGENBCY STOP ALARM – DISABLE 25. EMERGENCY STOP TRIP – DISBLE26. INTERNAL FAILURE PLC RESET – DIS 527. INTERNAL FAILURE PANEL RST – DIS28. INTERNAL FAILURE AUTO RST – DIS29. INTERNAL FAILURE ALARM – EN30. INTERNAL LFAILURE TRIP – EN31. SER. PORT FAILURE PLC RESET – EN32. SER. PORT FAILURE PANEL RESET – EN33. SER. PORT FAILURE AUTO RESET – EN34. SER. PORT FAILURE ALARM RESET – EN35. SER. PORT FAILURE TRIP RESET – EN36. E/F TRIP PLC RESET - DIS37. E/F TRIP PANEL RESET - DIS38. E/F TRIP AUTO RESET – DIS39. E/F TRIP ALARM – EN40. E/F TRIP TRIP – EN41. E/F PRE ALARM PLC RESET - EN42. E/F PRE ALARM PANEL RESET - EN43. E/F PRE ALARM AUTO RESET - DIS44. E/F PRE ALARM ALARM RESET - EN45. E/F PRE ALARM TRIP RESET – DIS46. TRMPARETURE 3 TRIP PLC RESET - EN47. TRMPARETURE 3 TRIP PANEL RESET – EN48. TRMPARETURE 3 TRIP AUTO RESET – DIS49. TRMPARETURE 3 TRIP ALARM RESET - EN50. TRMPARETURE 3 TRIP TRIP RESET – EN51. TRMPARETURE 2 TRIP PLC RESET - EN

52. TRMPARETURE 2 TRIP PANEL RESET – EN53. TRMPARETURE 2 TRIP AUTO RESET – DIS54. TRMPARETURE 2 TRIP ALARM RESET - EN55. TRMPARETURE 2 TRIP TRIP RESET – EN56. TRMPARETURE 1 TRIP PLC RESET - EN57. TRMPARETURE 1 TRIP PANEL RESET – EN58. TRMPARETURE 1 TRIP AUTO RESET – DIS59. TRMPARETURE 1 TRIP ALARM RESET - EN60. TRMPARETURE 1 TRIP TRIP RESET – EN61. TEMPARETURE 3 PRE ALRAM PLC RESET - EN62. TEMPARETURE 3 PRE ALRAM PANEL RESET - EN63. TEMPARETURE 3 PRE ALRAM AUTO RESET - DIS64. TEMPARETURE 3 PRE ALRAM ALARM RESET - EN65. TEMPARETURE 3 PRE ALRAM TRIP RESET – EN66. TEMPARETURE 2 PRE ALRAM PLC RESET - EN67. TEMPARETURE 2 PRE ALRAM PANEL RESET - EN68. TEMPARETURE 2 PRE ALRAM AUTO RESET - DIS69. TEMPARETURE 2 PRE ALRAM ALARM RESET - EN70. TEMPARETURE 2 PRE ALRAM TRIP RESET - EN71. TEMPARETURE 1 PRE ALRAM PLC RESET - EN72. TEMPARETURE 1 PRE ALRAM PANEL RESET - EN73. TEMPARETURE 1 PRE ALRAM AUTO RESET - DIS74. TEMPARETURE 1 PRE ALRAM ALARM RESET - EN75. TEMPARETURE 1 PRE ALRAM TRIP RESET – EN76. PHASE SEQUENCE PLC RESET – EN77. PHASE SEQUENCE PANEL RESET – EN 678. PHASE SEQUENCE AUTO RESET – EN79. PHASE SEQUENCE ALARM RESET – DIS80. PHASE SEQUENCE TRIP RESET – DIS81. PHASE LOSS PLC RESET – EN82. PHASE LOSS PANEL RESET – EN83. PHASE LOSS AUTO RESET – DIS84. PHASE LOSS ALARM RESET – DIS85. PHASE LOSS TRIP RESET - DIS86. O/V TRIP PLC RESET – EN87. O/V TRIP PANEL RESET - EN88. O/V TRIP AUTO RESET - DIS89. O/V TRIP ALARM RESET - EN90. O/V TRIP TRIP - EN91. O/V PRE ALARM PLC RESET – EN92. O/V PRE ALARM PANEL RESET - EN93. O/V PRE ALARM AUTO RESET - DIS94. O/V PRE ALARM ALARM RESET - EN95. O/V PRE ALARM TRIP - DIS96. UNDER VOLTAGE PLC RESET – EN97. UNDER VOLTAGE PANEL RESET - EN98. UNDER VOLTAGE AUTO RESET – DIS99. UNDER VOLTAGE ALARRM RESET – EN100. UNDER VOLTAGE TRIP RESET – EN101. UNBALANCE TRIP PLC RESET – EN102. UNBALANCE TRIP PANEL RESET – EN

103. UNBALANCE TRIP AUTO RESET – DIS104. UNBALANCE TRIP ALARM RESET – EN105. UNBALANCE TRIP TRIP RESET – EN106. UNBALANCE ALARM PLC RESET – EN107. UNBALANCE ALARM PANEL RESET – EN108. UNBALANCE ALARM AUTO RESET – DIS109. UNBALANCE ALARM ALARM RESET – EN110. UNBALANCE ALARM TRIP RESET – EN111. THERMAL O/C TRIP PLC RESET - EN 112. THERMAL O/C TRIP PANEL RESET - EN113. THERMAL O/C TRIP AUTO RESET - DIS114. THERMAL O/C TRIP ALARM RESET - EN115. THERMAL O/C TRIP TRIP RESET - EN116. THERMAL PRE ALARM PLC RESET - EN 117. THERMAL PRE ALARM PANEL RESET - EN118. THERMAL PRE ALARM AUTO RESET - DIS119. THERMAL PRE ALARM ALARM RESET - EN120. THERMAL PRE ALARM TRIP RESET – DIS121. HIGH SET O/C PLC RESET - EN122. HIGH SET O/C PANEL RESET - EN123. HIGH SET O/C AUTO RESET - DIS124. HIGH SET O/C ALARM RESET - DIS125. HIGH SET O/C TRIP RESET - DIS126. LOW SET O/C PLC RESET - EN127. LOW SET O/C PANEL RESET - EN128. LOW SET O/C AUTO RESET – DIS 7129. LOW SET O/C ALARM RESET - DIS130. LOW SET O/C TRIP RESET – DIS131. U/C TRIP PLC RESET - EN132. U/C TRIP PANEL RESET - EN133. U/C TRIP AUTO RESET - DIS134. U/C TRIP ALARM RESET - DIS135. U/C TRIP TRIP RESET - DIS136. U/C PRE ALARM PLC RESET - EN137. U/C PRE ALARM PANEL RESET - EN138. U/C PRE ALARM AUTO RESET - DIS139. U/C PRE ALARM ALARM RESET - DIS140. U/C PRE ALARM TRIP RESET – DIS141. TOO MANY STARTS PLC RESET - EN142. TOO MANY STARTS PAENL RESET - EN143. TOO MANY STARTS AUTO RESET - DIS144. TOO MANY STARTS ALARM RESET - EN145. TOO MANY STARTS TRIP RESET – EN146. MAX.START TIME PLC RESET - EN147. MAX.START TIME PANEL RESET - EN148. MAX.START TIME AUTO RESET - DIS149. MAX.START TIME ALARM RESET - EN150. MAX.START TIME TRIP RESET – EN

DATA PAGE

1. MEASURE DATA

1. T1, T2, T3—53,55,54 Degre.C2. POWER FACTOR 52%3. T;VA POWER 422.7 KVA4. T; REAL POWER 225.6 KW5. EARTH FAULT CURRENT ; 0.0A6. I1, I2, I3 ; 42,42,427. VL12,VL23,VL31—0,0,0.8. VP1,VP2,VP3—3.34,3.34,3.34V

2.CALCULATED DATA

1. UNBALANCE CURRENT 1%2. TIME TO START 0 SEC3. TIME TO TRIP NO TRIP EXPECTED4. THERMAL CAPACITY 17% OF CAPACITY5. MOTOR LOAD 68% OF FLC

83.LOGICAL INPUTS CONTACT STATUS

1. EXTERNAL FAULT 3 OPEN - STOP2. EXTERNAL FAULT 2 OPEN – STOP 3. EMERGENCY STOP OPEN – STOP4. AUTHORISED KEY CLOSED- UN LOCKED5. SPEED SWITCH OPEN- HIGH SPEED6. DRIVE STATUS- RUNING

4.STATISTICAL DATA

1. LAST ST. PEAK –I-280AMP 2. LAST ST,PERIOD – 2.1SEC3. TOTAL # OF TRIPS 254. TOTAL # OF START 1985. TOTAL RUN TIME 19307 HOURS

5. FAULT DATA

1. TRIP V1,V2,V3---3.3,3.3,3.3 K.V2. TRIP TO 0.0 AMP3. TRIP I1,I2,I3---275,285,280 AMP

4. LAST ALARM TOO MANY STARTS5. LAST TRIP TOO MANY STARTS

9

INTERNATIONAL STANDARD RELAYS NO.S

1. MASTER ELEMENT

2. TIME DELAY STARTING OR CLOSING RELAY

3. CONTROL SWITCH CHECKING OR INTERLOCKING RELAY

4. MASTER CONTACTOR OR RELAY

5. STOPPING DEVICE

6. STARTING CIRCUIT BREAKER , CONTACTOR , SWITCH OR RELAY

7. REGULATING SWITCH (ANODE CIRCUIT BREAKER)

8. CONTROL POWER DISCONNECTING DEVICE

9. REVERSE FIELD DEVICE

10. UNIT SEQUENCE SWITCH OR PROGRAMMABE DEVICE

11. TESTING SWITCH OR RELAY

12. OVER SPEED DEVICE

13. SYNCHROUNOUS SPEED DEVICE

14. UNDER SPEED DEVICE

15. SPEED OR FREQUENCY MATCHING DEVICE

16. PILOT WIRE FAULT PROTECTIVE RELAY

17. PILOT WIRE RELAY (SHUNTING OR DISCHARGE SWITCH)

18. ACCELRATING OR DECCELRATING DEVICE

19. STARTING TO RUNNING TRANSITION CONTACTOR OR RELAY

20. VALVE FOR AUXILARY APPARATUS

21. VALVE FOR MAIN MACHINES (DISTANCE RELAY)

22. SPARE NUMBER (EQUALISER CIRCUIT BREAKER)

23. TEMPARATURE CONTROL DEVICE

24. TAP CHANGING MECHANISM

25. SYNCHRONOUSING OR SYNCHRONOUSING CHECK DEVICE

26. THERMAL RELAY FOR STATIONERY APPARATUS

27. AC UNDER VOLTAGE RELAY

28. ALARM DEVICE (FLAME DETECTOR)

29. FIRE EXTINGUISHER (ISOLATING CONTACTOR)

30. ANNONCIATOR

31. SEPARATE EXCITATION DEVICE

32. DC REVERSE CURRENT RELAY (DIMENTIONAL POWER RELAY)

33. POSITION SWITCH

34. MOTOR OPERATED SEQUENCE SWITCH (MASTER SEQUENCE RELAY)35. BRUSH OPERATING OR SLIPRING SHORT CIRCUITING DEVICE

36. POLARITY RELAY

37. UNDER CURRENT RELAY

38. THERMAL RELAY FOR BEARING HT MOTOR

39. SPARE NUMBER (MECH CONDITION MONITOR)

40. FIELD CURRENT RELAY OR LOSS OF FIELD RELAY

41. FIELD CURRENT BREAKER , CONTACTOR OR SWITCH

42. RUNNING CURRENT BREAKER , CONTACTOR OR SWITCH

43. CHANGE OVER SWITCH (SELECTOR DEVICE)

44. DISTANCE RELAY (UNIT SEQUENCE STARTING RELAY)

45. DC OVER VOLTAGE RELAY (ATTN CONDITION MONITOR)

46. REVERSE PHASE OR PHASE UNBALANCE CURRENT RELAY - HT MOTOR

47. PHASE SEQUENCE VOLTAGE RELAY

48. INCOMPLETE SEQUENCE RELAY

49. THERMAL RELAY FOR ROTATING MACHINES HT MOTOR

50. SHORT CIRCUIT SELECTIVE RELAY OR GROUND SELECTIVE RELAY HT MOTOR

51. AC OVER CURRENT RELAY OR GROUND OVER CURRENT RELAY

52. AC CIRCUIT BREAKER OR CONTACTOR

53. EXCITATION RELAY

54. DC HIGH SPEED CIRCUIT BREAKER

55. AUTOMATIC POWER FACTOR REGULATOR OR POWER FACTOR RELAY56. SLIP RELAY OR OUT OF STEP RELAY (FIELD APP. RELAY)

57. AUTOMATIC CURRENT REGULATOR OR CURRENT RELAY (SC & GROUND DEVICE)

58. SPARE NUMBER (RECTIFICATION FAILURE RELAY)

59. AC OVER VOLTAGE RELAY

60. AUTOMATIC VOLTAGE BALANCE REGULATOR OR VOLTAGE BALANCE RELAY

61. AUTOMATIC CURRENT BALANCE REGULATOR OR CURRENT BALANCE RELAY

62. TIME DELAY STOPPING OR OPENING RELAY

63. PRESSURE RELAY (VACCUM RELAY)

64. GROUND OVER VOLTAGE RELAY

65. GOVERNOR

66. FLASHER RELAY NOTCHING OR TAGGING DEVICE

67. AC POWER DIRECTIONAL OR GROUND DIRECTIONAL RELAY

68. IMPURITY DETECTOR (BLOCKING RELAY)

69. FLOW RELAY (PERMESSIVE CONTROL DEVICE)

70. RHEOSTAT

71. RECTIFIER FAULT DETECTOR (LIQUID OR GAS LEVEL RELAY)

72. DC CIRCUIT BREAKER OR CONTACTOR

73. SHORT CIRCUTING CIRCUIT BREAKER OR CONTACTOR

74. REGULATING VALVE (LOAD RESISTANCE OR CONTACTOR)

75. DAMPING DEVICE (POSITION CHANGING MECHANISM)

76. DC OVER CURRENT RELAY

77. LOAD REGULATING DEVICE (PULSE TRANSMISSION)

78. PHASE COMPARRISION RELAY

79. AC RECLOSING RELAY

80. DC UNDER VOLTAGE RELAY (LIQUID OR GAS FLOW RELAY)

81. GOVERNOR DRIVING GEAR (FREQUENCY RELAY)

82. DC RECLOSING RELAY

83. SELECTIVE CONTACTOR OR SELECTIVE RELAY

84. VOLTAGE RELAY (OPERATING MECH)

85. CARRIER OR PILOT WIRE RECEIVER RELAY

86. LOCK OUT RELAY HT MOTOR

87. DIFFERENTIAL CURRENT RELAY

88. AUXILARY CONTACTOR OR SWITCH

89. DISCONNECTING SWITCH (LINE SWITCH)

90. AUTOMATIC VOLTAGE REGULATOR OR REGULATING RELAY

91. AUTOMATIC POWER REGULATOR OR POWER RELAY (VOLTAGE DIRECTION)

92. DOOR (VOLTAGE AND POWER DIRECTIONAL RELAY)

93. SPARE NUMBER (FIELD CHANGING CONTACTOR)

94. TRIP FREE CONTACTOR OR RELAY

95. AUTOMATIC FREQUENCY REGULATOR OR FREQUENCY RELAY HT MOTOR

96. INTERNAL FAULT DETECTOR FOR STATIONARY INDUCTION APPARATUS97. RUNNER

98. CONNECTING DEVICE

99. AUTOMATIC RECORDING DEVICE

100 RUN HOUR METER HT MOTOR