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notlost · 05-02-2014, 01:07 PM

The generator frequency varies from 57-63 hz. this seems to only happen when there is no load.
under load (even a small 8amp heater) i seem to keep steady at 60 hz (it did go to 61 for a very short time).
is this normal, or should i take any action? we are headed to alaska and expect to be doing a good amount of dry camping.
i don't want to worry needlessly, but also don't want to have problems up north.
thanks

gemini5362 · 05-02-2014, 04:35 PM

hopefully someone with one of these units will see your post. IF the 10k is the same as my 7500 Onan diesel generator it has a inverter to power it. The generator either produces dc or it is rectified I am not sure which then that is fed into an inverter to produce 60 cycle power. IF that is how they work. ( I do not work on these so I could be wrong) then I would not expect it to vary hardly at all. The 60 cycle should be slaved to a crystal controlled oscillator and be very steady load or no load. Either way I am sure if I am wrong someone will point it out to me and I can learn something new.

calhyatt · 05-03-2014, 07:18 AM

As long as the freq is stable under load I would run it. The small oscillations you describe are absolutely no trouble for your equipment. IMHO.

dvmweb · 05-03-2014, 01:26 PM

How many hours? Even when warmed up? Call Onan. But, I would think that not unusual.

94-Newmar · 05-04-2014, 06:32 AM

Notlost, posting your exact model # will certainly help in the future. For now I'll assume it's an HDK series QuietDiesel, inverter type generator - if so, the rpm will increase as load on the generator is increased. Being an inverter type generator, the rotor speed (RPM) has nothing to do with the cycles, and instead is entirely controlled by the electronic control board. It is not uncommon on the inverter style generators to see minor fluctuations in HZ when there is less than 5 watts load on the unit.

gemini5362 · 05-04-2014, 08:57 AM

Quote:

Originally Posted by 94-Newmar

Notlost, posting your exact model # will certainly help in the future. For now I'll assume it's an HDK series QuietDiesel, inverter type generator - if so, the rpm will increase as load on the generator is increased. Being an inverter type generator, the rotor speed (RPM) has nothing to do with the cycles, and instead is entirely controlled by the electronic control board. It is not uncommon on the inverter style generators to see minor fluctuations in HZ when there is less than 5 watts load on the unit.

I am not arguing with your post just curious if you know why they have a variation. Inverter boards should just be SCR devices that are turned on and off by an oscillator. I would have though that these oscillators are crystal controlled which should be very stable and the load should not make a difference ?

94-Newmar · 05-04-2014, 03:38 PM

Yea, not sure why... I see it all the time on the QuietDiesel inverter gensets. Erratic HZ then just add a small load, even a few watts - not even enough load to make the rpm leave idle speed, and it cleans up instantly.

notlost · 05-04-2014, 11:09 PM

I do have the model number it is 10HDCAA11506A. I appreciate any further input that you may have. I tried running the gen today again. And the same conditions happened. From the start up and with nothing on in the coach there is a fluctuation of the Hz. When we put on an 8-10 amp load the Hz level out to a solid 60Hz. Do you still feel this is normal giving you the model number do you know if we have an inverter type generator? I really appreciate your help. Notlost