Whisper Power M-SC6, User Manual

Page: 34 / 44

TROUBLE SHOOTING
34
December 2010 / M-SC6/8/10 / EN
5.3.3 Winding resistant values
If after establishing and correcting any fault on the
capacitor and diodes output is still low when separately
excited, then the main rotor, stator and exciter stator
winding resistance should be checked as the fault must be
in one of these windings. The respective leads must be
disconnected before taking the readings.
Resistance values should be within 10% of the values
given in the table below:
M-SC6 and 8
Resistance 50Hz
•
Resistance both main stator windings
in series
0.54 Ohm
•
Resistance both rotor windings
0.93 Ohm
•
Resistance exciter stator winding
1.4 Ohm
M-SC10
Resistance 50Hz
•
Resistance both main stator windings
in series
0.36 Ohm
•
Resistance both rotor windings
1.05 Ohm
•
Resistance exciter stator winding
0.85 Ohm
5.3.4 Meggering
One can try to measure resistance between the housing
and the windings with a multimeter which should read
infinity. When readings are infinity but a fault is suspected
one can do a high voltage resistance test (MEGGERING)
This procedure should be carried out by an expert
5.4 SPECIAL PROCEDURES ENGINE
5.4.1 Setting the RPM
RPM is set by the manufacturer and should not need
readjustment! However a very slight offset after running in
could occur. RPM can be measured by a frequency meter.
M-SC8 and 10:
When adjustments are necessary this can
only be done with the help of an interface to a computer
and special software to get access to the microprocessor.
If readjustment of the RPM is necessary, please contact
your WhisperPower Service Centre for advice.
M-SC6:
Before readjustment check any other explanation
for the wrong speed. Engine speed is set at the factory at
nominal 3000 (50 Hz) RPM. A RPM drop of 5% at full load
is acceptable. Therefore a no load setting should be at ±
3150 RPM = 52.5 Hz. Under no circumstances should the
RPM be under full load below 2940 RPM = 49 Hz.
When no cause can be found for a wrong speed, the
setting can be adjusted:
Fig. 22
2= adjustment screw RPM
3= manual stop
It is very important to identify the correct setting assembly
(refer to fig. 22).The screw is to be locked in position with
the lock-nut.
1
2
3