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9 TROUBLESHOOTING
Problem
alternator set is not generating any
voltage.
When load is applied, the generated
voltage decreases and it doesn't
return to the setpoint.
Overvoltage without control.
alternator voltage low and doesn't
increase.
Generated voltage oscillates when
there is no load.
NOTE
If the procedure suggested above doesn't solve the problem, the regulator must be
replaced.
10 WARRANTY
See the Installation and Maintenance Manual of the alternator Weg.
20 | Automatic Voltage Regulator - K38L
Causes
Residual Voltage is too low.
Field terminals (F+ and F-) are inverted.
Alternator is overloaded.
Subfrequency protection is active.
SW2 may be incorrect.
Faulty voltage regulator.
No sensing voltage found and the
protection against loss of sensing
voltage is active.
Voltage set far below the rated voltage.
alternator field voltage is too low.
Solution
With an independent 12V battery,
excite the alternator field. The genset
battery can't be used for this purpose.
Reverse the alternator field polarity (F+
and F-).
Decrease the load applied to the
alternator.
Turn slowly counter-clockwise the U/F
potentiometer.
Correct the switch SW2.
Replace the voltage regulator.
Correct the electrical installation,
making sure that the sensing voltage
are coming to the regulator.
Adjust the voltage in the VOLT pot.
Connect a 15Ωx200W resistor in series
with the alternator field.