Winco MD6L - Manual (Page 13)

PAGE 11 60706-121
DIAGNOSTIC TABLE
GENERATOR
SYMPTOM
POSSIBLE CAUSE
CORRECTION
LOW VOLTAGE (UNDER 220 VOLTS LOADED)
Engine Speed too Slow Check the no-load engine speed with a frequency meter and adjust
the governor to 61.5 Hertz at no-load. Troubleshoot engine and deter- mine why it will not hold the
proper speed.
Generator Overloaded Measure load being run and compare with nameplate rating. The load
on each leg should be as evenly balanced as possible and should not exceed the rated current on
any leg.
LOW VOLTAGE (UNDER 230 VOLTS NO LOAD)
Engine Speed too Slow Check the no-load engine speed with a frequency meter and adjust the
governor to 61.5 Hertz at no-load.
Generator Overloaded Measure load being run and compare with nameplate rating. The load
on each leg should be as evenly balanced as possible and should not exceed the rated current on
any leg.
Defective Main Rotor Measure rotor resistance (Rotating Fields). Check for grounds. Replace
if defective.
Defective Capacitor Test and replace if defective.
LOW VOLTAGE (3 TO 40 VOLTS)
Loose or Shorted Wires in Check all wiring and repair as needed.
Control Cabinet
Defective Diode Follow test procedure and replace if defective.
(Rotating Excitation)
Defective Excitor Winding Measure the resistance of the two leads connected to the capacitor,
Repair or replace as required. Check for grounds.
Defective Capacitor Test for opens and shorts. Replace if defective.
(Excitor)
Defective Main Rotor Measure rotor resistance (Rotating Field). Check for grounds. Replace
if defective.