Engine Faults; General - Whisper Power W-SQ25 User Manual

TROUBLE SHOOTING
PROBLEM
than 225V between phase and
neutral).
Generator output voltage too
low under load (less than 225V).
In no load condition it is OK
Generator output voltage too
high, (more than 235V)
Generator output voltage too
high, (more than 235V)
In no load condition it is OK
Generator voltage fluctuates.
Generator is not able to start an
electric motor
5.2

ENGINE FAULTS

Remove 3 Amp. fuse in the control panel
while working on the generator to prevent the
engine from starting.
5.2.1

General

Most electrical problems relating to Voltage or Frequency
are due to wrong engine speed. Note that RPM and Hz
are basically the same.
Use the problem solving table to find the cause of a wrong
engine speed. When there is no obvious cause one can
adjust the RPM (refer to special procedures).
28
CAUSE
• Faulty AVR. When slightly too low,
adjustment could be necessary
• Defective diode
• When
applying 3
unbalanced load; check the voltage of
the other phases. When the voltages
are different this is caused by an
unbalanced load.
• Engine is not reaching the rated RPM.
Possibly too much load or engine
problems (lack of fuel)
• Faulty AVR or readjustment necessary
• Over-energising due to defective AVR
or wrong AVR setting
• Unbalanced load
• Disturbances on the electrical system/
user side.
• AVR reacts on fluctuating load
• Engine runs irregularly.
If the generator is unable to supply
enough power to start an AC electric
motor, this is usually because this motor
draws too much current during starting
As the alternator is very much under-
rated the problem will appear by the
engine RPM collapsing
SOLUTION
Try to readjust AVR. Check by independent
excitation if the problem is in the AVR or in the
windings and replace AVR if necessary (see
special procedures).
Check the diode in the rotor (see special
procedures). The
block/rectifier unit.
Bring load in balance. When slightly out of
phase: an
balance, remove the sense wires to the phase
with the highest load and check if the voltage
on the other phases is not too high.
Switch off a load; (part off) consumers
See to engine RPM problems
Try to readjust the voltage
Check by independent excitation if the problem
is in the AVR or in the windings and replace
AVR if necessary (see special procedures).
Check AVR, readjust and replace if necessary
capacitor specification and replace AVR if
necessary (see special procedures)..
Bring load in balance.
When slightly out of balance, remove the
sense wires to the phase with the highest load
and check if the voltage on the other phases is
not too low.
Check if electrical load is fluctuating
Readjust the stability setting on the AVR
trimmer "ST"
When engine runs irregularly see section:
"Engine runs irregularly" at the "Engine faults"
paragraph.
Check the electric motor's current draw
required for starting. This should not exceed
the rated generator output current. This could
be remedied by using a "soft-start". Inquire at
your nearest
at the manufacturer,
Netherlands.
When the engine is not cranking well, starting problems
almost always originate from battery problems or poor
battery cable connections.
When the engine is cranking, well starting problems
almost always originate from lack of fuel or air bubbles in
the fuel pipes.
A failure code is displayed when a hardware failure at the
generator is detected.
January 2009 / W-SQ25 for mobile applications / EN
W-SQ25 has one diode
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