For more detail of installation, commissioning and trouble shooting, please click here..

» SELECTION OF SITE

» FOUNDATION DETAILS AND GUIDELINES

» EARTHING SYSTEM

» EXHAUST PIPING

» FUEL PIPING

» CABLING

» BATTERY CHARGING PROCEDURE

» SUMP CAPACITY (LITRES)

» CHECK UP BEFORE STARTING THE DG SET

» PRE-COMMISSIONING CHECK

» ROUTINE CHECK POINTS

» DO'S & DON'T'S

» TROUBLE SHOOTING - ENGINE

» TROUBLE SHOOTING CHART : ALTERNATOR

» TROUBLE SHOOTING GUIDE FOR MANUAL PANEL

» TROUBLE SHOOTING GUIDE FOR AMF PANEL

TROUBLE SHOOTING CHART : ALTERNATOR

Fault Cause Rectification

No voltage build - up 1) Insufficient residual voltage.2) Improper connection3) Low speed4) Faulty Winding5) Rotating rectifier fai lure6) Faulty AVR

1) Excite the rotor using a battery.2) Correct the connection3) Reset the speed to the nominal.4) Check the winding resistance and rewind ifrequired.5) Replace the rotating required.6) Replace the AVR

Low no-load voltage 1) Low Speed

2) Faulty Rotating rectifier

3) Faulty Winding

1) Reset the speed to the nominal2) Replace the rotating rectifier.3) Check the winding resistanceand rewind if required.

Low voltage on load1) Low speed at ful l load

2) AVR faulty3) Faulty rotor winding4) Over load on alternator

1) Set the rated speed of the prime mover.2) Change AVR3) Check the rotor winding resistance and if faulty,rewind it.4) Operate on specified load.

High voltage on load 1) Capacitors on the load side2) Faulty AVR setting orAVR is faulty

1) Disconnect the PFimprovement capacitors2) Correct the setting/ReplaceAVR

Too highno-load voltage

1) Excessive speed2) Correct the settingReplace AVR

1) Adjust the revolving speedCorrect the settingReplace AVR

Fault Cause Rectification

Voltage oscil lations 1) Incorrect AVR Setting2) Thyristor load more that specified l imits3) Insufficient engine flywheel

1) Set the AVR stabil i ty pot2) Reduce the Thyristor load

Unbalance Voltage 1) Unbalance load2) Loose connections3) Stator winding faulty

1) Correct the load2) Tighten the loose connections3) Check winding resistance& rewind if required.

Generator does not share(2 Generators inParallel OperationKW load proportionately

Prime mover speed droop Set prime mover speed properly.

Improperly set Droop (Governor)characteristic of engines.

Generator does not shareKVAr load proportionately

Quadrature droop Interchange CT secondary

Incorrect Correctly by QDC Pot in AVR.

QDC-CT polarity reversed Interchange CT secondary

QDC-CT are not inW-phase

Check and rectify

Excessive overheating of one or bothbearings (temp. of bearings over80ºC)(with or without noise)

1) Set misalignment2) Bearing loose in end shield housing

1) Align the set properly2) Replace the faulty EndShield

Fault Cause Rectification

Excessive overheating of alternator frame 1) Air flow (inlet-outlet) partial ly clogged or hotair is being circulated either from alternator orprime mover2) Alternator operatingat high Voltage at load3) Alternator overloaded4) Load PF less then0.8 lag.

1) Check air inlet - outlets of the alternator2) Set the voltage to rated value3) Operate at specified load4) Correct the load power factor

Excessive Vibrations Defective mounting or play inthe couplingLoose mounting Bolts

Replace the coupling & check the alignment Resetthe speed to the nominal

Excessive vibration and humming noisecoming from the alternator

1) Three phase alternatoris single phase loaded in excess of acceptablel imits2) Start up with no-load:if humming persists-faulty alternator statorwinding

1) Check and correct the load2) Rewind stator

Smokes, spark or flames coming from thealternator

Short circuit in the external circuit (includingwiring between alternatorand control board)Object fal len into the machine short circuit orflash in the stator winding

Stop the gen-set immediately

Fault Cause Rectification

Alternator damaged by as significantimpact which is fol lowed by hummingand vibration

Short circuit in external circuit faulty parallelconnection (out of phase) Break or deteriorationin the coupling Break or twist in shaft extensionshifting or circuit of main field winding Burstingor unlocking of the fan Diode burnt, rectifierbridge damaged.

Stop the gen-set immediately