AVR Comparision

A V R COMPARISION CHART SX 460

SX 440

SX 421

MX 341

MX 321

Used on m/cs from 30-200 KVA, UC frame machine.

Used on m/cs from 210-650 KVA, HC4 & HC5 frame machines.

Used on m/cs from 210-650 KVA HC4 & HC5 frame machines.

Used on m/cs from 30-650 KVA I.e. UC22,27 & HC4, HC5 frame m/cs with PMG as optional.

Used on m/cs from 725 KVA & above I.e. HC6 & HC7 frame machines.

2 phase sensing. Terminal 7,8 from main stator are, Power & sensing input for AVR. Power - Connect 7 , 8 from main stator to 7 , 8 of AVR.

3 phase sensing. Terminals 6, 7,8 sensing & power input from main Stator of m/c to AVR. Power - Connect 6, 7, 8 from main Stator to P4, P3, P2 of AVR respectively.

2 phase sensing. Terminal 7,8 sensing I/p from main stator & Power input from PMG to AVR. Power - Connect P2 , P3 from PMG to P2 , P3 of AVR respectively.

3 phase sensing terminals 6,7,8 from Isolation Transformer Secondary & power input from PMG.

Sensing - Connect 7, 8 from main stator to 7, 8 of AVR.

2 phase sensing. Terminal 7,8 sensing & power input from main stator of m/c to AVR. Power - Connect 7 & 8 from main stator to P3 & P2 of AVR. respectively. Sensing - Connect 7 & 8 from main stator to 3 & 2 of AVR respectively.

Sensing - Connect 6, 7, 8 from main stator to, 6, 7, 8 of AVR terminals respectively.

Sensing - Connect 7 & 8 from main Stator to 3 & 2 of AVR respectively.

Sensing - Connect 6, 7, 8 from Isolation Transformer secondary to 6, 7, 8 of AVR respectively.

AVR DC output X, XX OR F1 F2, to Exciter Stator ( I.e. +ve, - ve ) respectively.

AVR DC output X, XX OR F1 F2 to Exciter Stator ( I.e. +ve, - ve )

AVR DC output X, XX OR F1 F2 to Exciter Stator ( I.e. +ve, - ve )

AVR DC output X, XX OR F1 F2 to Exciter Stator ( I.e. +ve, - ve ).

AVR DC output X, XX OR F1 F2 to Exciter Stator ( I.e. +ve, - ve )

Used with SELF EXCITED, non PMG machine.

Used with SELF EXCITED MACHINE WITHOUT PMG.

Used with SELF EXCITED MACHINE WITHOUT PMG.

Used with SEPARATELY EXCITED MACHINE WITH PMG.

Used with SEPARATELY EXCITED MACHINE WITH PMG.

Excitation Interruption link, K1, K2, not provided.

Excitation interruption link K1, K2 provided. ( Always short externally )

Excitation interruption link K1, K2 NO EXTERNAL SHORT LINK. K1, K2 control thru B0, B1 coil supply control. During High excitation, coil at B0, B1 activates & opens link at K1 , K2 thus interrupts excitation.

Excitation interruption link K1, K2 provided. ( Always short externally )

Excitation interruption link K1, K2 NO EXTERNAL SHORT LINK. K1, K2 control thru B0, B1 coil supply control. During High excitation, coil at B0, B1 activates & opens link at K1 , K2 thus interrupts excitation.

Stability selection Frame UC 22, HC 4,5 - Link BC ( 90 KW - 550 KW )

Stability selection Frame UC 22, HC 4,5 ( Under 90 KW ) - Link AC

Frame UC 27, HC 6,7 - Link A,B ( Over 550 KW )

( 90 KW to 550 KW ) - Link BC Frame UC 27, HC 6,7( Above 550 KW ) - Link AB. Frequency selection 4 Pole 50 HZ - LINK 4 Pole 60 HZ - LINK 6 Pole 50 HZ 6 Pole 60 HZ - LINK

Stability selection Frame UC 22, HC 4,5 - Link BC ( 90 KW - 550 KW )

- Connect P2, P3, P4 from PMG to P2, P3, P4 of AVR respectively.

Frame UC 27, HC 6,7 - Link A,B ( Over 550 KW )

Stability selection Under 40 KW 40 KW - 90 KW 90 KW - 550 KW Over 550 KW

Frequency selection 50 HZ - LINK C - 50. 60 HZ - LINK C - 60.

Frequency selection 50 HZ - LINK C - 50 60 HZ - LINK C - 60

Frequency selection 50 HZ - LINK C - 50 60 HZ - LINK C - 60

Frequency selection 4 Pole 50 HZ - LINK 4 Pole 60 HZ - LINK 6 Pole 50 HZ 6 Pole 60 HZ -

External Hand Trimmer for,REMOTE VOLTAGE ADJUSTMENT. No Trimmer - Link 1 , 2. For Trimmer - Remove Link at 1,2 & connect trimmer here.

External Hand Trimmer for,REMOTE VOLTAGE ADJUSTMENT No Trimmer - Link 1 , 2. For Trimmer - Remove Link at 1 , 2 & connect Trimmer here. TRIMMER - 1 K Ohm / 1 Watt

External Hand Trimmer for,REMOTE VOLTAGE ADJUSTMENT No Trimmer - Link 1 , 2. For Trimmer - Remove Link at 1 , 2 & connect Trimmer here.

External Hand Trimmer REMOTE VOLTAGE ADJUSTMENT No Trimmer - Link 1 , 2. For Trimmer - Remove Link at 1 , 2 & connect Trimmer here.

External Hand Trimmer REMOTE VOLTAGE ADJUSTMENT No Trimmer - Link 1 , 2. For Trimmer - Remove Link at 1, 2 & connect Trimmer here.

TRIMMER

TRIMMER

TRIMMER

AVR input selection Link 2 - 3, 4 - 5, 6 - 7 at AVR.

AVR input selection - N. A.

AVR input selection,Link 2 - 3, 4 - 5, 6 - 7 at AVR.

Terminals A1, A2 used only in parallel operation with grid. Wires from Power Factor Controller need to be connected to A1, A2. NORMALLY KEEP OPEN.

Terminals A1, A2 used only in parallel operation with grid. Wires from Power Factor Controller need to be connected to A1, A2. NORMALLY KEEP OPEN.

Terminals A1, A2 used only in parallel operation with grid. Wires from Power Factor Controller need to be connected to A1, A2. NORMALLY KEEP OPEN.

Parallel operation :S1 , S2 terminals of Droop CT provided at W phase of machine need to be connected at S1 , S2 terminals of AVR respectively. S1, S2 terminal of AVR are of Voltage Droop.

Parallel operation :S1 , S2 terminals of Droop CT provided at W phase of machine need to be connected at S1 , S2 terminals of AVR respectively. S1, S2 terminal of AVR are of Voltage Droop.

Parallel operation :S1 , S2 terminals of Droop CT provided at W phase of machine need to be connected at S1 , S2 terminals of AVR respectively. S1, S2 terminal of AVR are of Voltage Droop.

Parallel operation :S1 , S2 terminals of Droop CT provided at W phase of machine need to be connected at S1 , S2 terminals of AVR respectively. S1, S2 terminal of AVR are of Voltage Droop.

Over Voltage Protection - N. A.

Over Voltage Protection :Connect E0 , E1 of AVR to terminals 7 & 8 at Isolation Transformer.

Over Voltage Protection - N. A.

Over Voltage Protection :Connect E0 , E1 of AVR to terminals 7 & 8 at Isolation Transformer.

Stability selection - N. A.

TRIMMER

- 1 K Ohm / 1 Watt.

AVR input selection 220 / 240 V input - No Link. High Voltage. 110 / 120 V input - Link 3 , 4. Low Voltage. For 415V output machine, NO LINK AT 3,4 IS REQUIRED.

- Link B D - Link A C - Link B C - Link A B

Power

- 1 K Ohm / 1 Watt

- 2 , 3. -1,3 - NO LINK - Link 1 , 2.

- 4.7 or 5 K Ohm / 1 Watt

- 2 , 3. -1,3 - NO LINK - 1 , 2.

- 4.7 or 5 K Ohm / 1 Watt

AVR input selection - N. A.

Terminals for Parallel Operation with Grid. NOT SUITABLE FOR PARALLEL OPERATION.

Over Voltage Protection - N. A.

( S1 - S2 ) - U / ( S1 - S2 ) - V / ( S1 - S2 ) W & A1, A2

NORMALLY KEEP OPEN.

AVR SETTING POTS & ADJUSTMENT PROCEDURES. POTS

AVR TYPE

PURPOSE

RAMP

MX 321

To control time taken by generator to build up voltage from initial to rated.

STABILITY

SX 460 SX 440 SX 421 MX 341 MX 321

To prevent voltage hunting ( fluctuation ) I.e. to provide damping effect.

VOLTS

SX 460 SX 440 MX 341

To adjust generator output voltage.

OVER VOLTAGE

SX 421 MX 321

Over Voltage Protection. To remove generator excitation in event of loss of AVR sensing input. SX 421 - Priovides only tripping signal for overvoltage Additional tripping circuit need to provide. MX 321 - It has internal de excitation system & also provides signal to use for tripping external circuit as Circuit Breaker. Incorrect setting LED will glow.

EXCITATION MX 341 TRIP MX 321

AVR detects high excitation & removes it after predetermined time 8 - 10 sec.

Only for m/cs with PMG

I ' LIMIT

To set maximum short circuit current capacity.

UFRO

SX 460 SX 440 SX 421 MX 341 MX 321

To set under Frequency Roll Off Point. All AVR's are incorporated with under speed protection Incorrect setting - LED will remain permanently ON. when generator is ON LOAD.

DIP

SX 421 MX 341 MX 321

Adjusts slope of voltage /speed ( HZ ) characteristic below the knee point.

DWELL

MX 321

To maintain time delay between recovery of voltage and speed. Dwell time delay is to reduce generator KW below available engine KW to allow improved speed recovery.

PROCEDURE

Standard Ramp time - 3 sec. can be reduced to - 1 sec. can be increased to - 8 second

- Factory set. - Fully anticlockwise. - Fully clockwise.

* Clockwise rotation of the pot increases damping effect and vice versa.

Clockwise rotation of the pot increases output voltage and vice versa.

Correct setting is 240 V across AVR terminal E1& E0. * Run the DG set on No Load at 1500 RPM. * Turn overvoltage pot fully clockwise. * Set output voltage of machine to 480 V with Volts pot. * Turn Overvoltage pot slowly anticlockwise. * At one point output voltage will collapse. This is correct point of setting. * Now turn Volts pot anticlockwise and stop DG set. * Restart DG set & run to 1500 RPM on no load. * Set output voltage of machine to 415 V with Volts pot. * Now overvoltage setting is set. * Now max. Overvoltage limit is 480 V.

Correct setting 70 V + 5 % DC between AVR terminals X, XX ( + , - ). LED will remain permanently ON during Excitation Trip. PMG being separate source for excitation supply, it can deliver max excitation during large overload or shortcircuit. This may cause to overvoltage and burn the winding. Hence to protect winding, Excitation trip protection is provided.

* Put generator off. * Remove short link at K1, K2 of AVR & connect 5A switch there. * Turn I limit pot fully anticlockwise. * Short all main stator winding at terminals & put clamp on Ammeter there. * Switch at K1, K2 keep open and start the generating set. * Close across K1, K2 & turn I limit clockwise until required current limit observed on the clamp on meter.

* As soon as required current limit reads, open the K1, K2 switch. If current collapses during procedure, * Shut down set & open K1, K2 switch. * Restart set for 10 min with K1, K2 open to cool generator winding. Running set for cooling without K1, K2 open may lead to damage the set.

Clockwise rotation reduces speed ( Frequency ) setting of KNEE POINT and LED becomes off. LED should on if frequency falls below 47 HZ ( on 50 HZ Generator ) Setting procedure :* Run DG on no load at 1425 RPM. * Turn UFRO pot fully anticlockwise, LED will become off. M/c vtg. Will be 415 V. * Now start turning UFRO pot slowly clockwise. * At one point LED will glow and voltage will drop down slightly. * Turn the UFRO pot slightly anticlockwise and LED will become off. * Again turn UFRO pot clockwise and LED will glow. * Now increase speed of engine to 1435 - 1440 RPM & LED will become off. * Now UFRO is set at 47.5 HZ. NOTE : for MX 341 & MX 321 if LED is glowing & no output voltage is present checkup with Excitation Trip and / or Overvoltage setting.

Clockwise adjustment of the pot increases dip in voltage and vice versa.

Clockwise adjustment gives increased recovery time.