Onan Adjustment
Is it possible to adjust the voltage output on an Onan 4K ? Mine runs ~109V no load, and sags to 105V at half load.
Forum Discussion
Depending on the "spec" letter, your KY Onan will have a voltage regulator separate from control board (around 2000, spec H and older).
Or the regulator is built into the control board (spec J and up).
Neither comes from Onan with a voltage adjust capability. As OP stated, verify your meter readings, the sign wave output is pretty "dirty" on
these sets, and an analog meter usually reads inaccurately.
Need to measure voltage and freq (hz) with a RMS digital meter. And yes, if engine running slow, voltage is affected. Governor speed should be adjusted at governor spring (NOT THROTTLE STOP SCREW) for ~62 hz no load, and if working correctly, will droop to ~59 hz or so at full load.
Vlotage should be ~125-115.
If speed correct, then possible causes are dirty rotor field brush slip rings, partially shorted rotor windings, or bad voltage regulator.
Or the regulator is built into the control board (spec J and up).
Neither comes from Onan with a voltage adjust capability. As OP stated, verify your meter readings, the sign wave output is pretty "dirty" on
these sets, and an analog meter usually reads inaccurately.
Need to measure voltage and freq (hz) with a RMS digital meter. And yes, if engine running slow, voltage is affected. Governor speed should be adjusted at governor spring (NOT THROTTLE STOP SCREW) for ~62 hz no load, and if working correctly, will droop to ~59 hz or so at full load.
Vlotage should be ~125-115.
If speed correct, then possible causes are dirty rotor field brush slip rings, partially shorted rotor windings, or bad voltage regulator.
