Troubleshooting - Sincro SK225 Serie Manual De Uso

8.4 Troubleshooting

Refer first to the troubleshooting guide of complete
alternator. In case that the power supply of AVR is
under suspect, performe following checks:
• Electrical: rotate the alternator to the nominal speed
and measure the voltage on the PMG outputs i.e.
on the input to the AVR supply (normally L and N
terminals on the AVR). The value should be 115 V
+/- 10% at 50 Hz in case of AVR DBL1 and 230 V
+/- 10% at 50 Hz in case of AVR BL4-U. In case
of additional doubts the PMG stator resistance
and insulation resistance should be checked.
Resistance values are 3,5 ohm +/- 5% for PMG in
case of digital AVR (AVR DBL1) and 14 ohm +/-
5% in case of alternator with analogue AVR (AVR
BL4-U). Insulation resistance should be >10 Mohm.
Mechanical: check if during nominal speed there is
•
abnormal sound from PMG and related excesive
vibrations. Also the temperature of external housing
of PMG have to be under 80°C.
This symbol signals risk conditions or
hazardous procedures that COULD cause
severe injury or death.
WARNING!
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