Onan Genset,voltage output exceeds 150 volts

[David Selby]

I have a 7.5 HDKAL 61730 Genset. I just noticed this high voltage (150 volts) today as I was running my gen. to test a new water heater element I has just installed. It does not matter whether I have both AC units and the water heater runnning or NO LOAD. What I did notice is that when first started there is the normal run time with no voltage, then the meter responds at about 105 volts for about 20 seconds, when the Heart Interface kicks in it then jumps to 150 and stays there. The Interface panel reads 14 volts @ 40 to 50 amps DC. I did accidentally shut down the Gen whie bothAC units and the water heater where on. I did not notice the voltage level before I did this. It was only when I restarted the Gen to see if there was a oroblem due to my shutdown error that I discovered this high voltage, even under load. I appreciate any insight anyone may have on this issue. The Heart Interface is a Freedom model 20. The Coach is a 1997 Gulf Strem Friendship 102. Thanks

[David Selby]

I have a 7.5 HDKAL 61730 Genset. I just noticed this high voltage (150 volts) today as I was running my gen. to test a new water heater element I has just installed. It does not matter whether I have both AC units and the water heater runnning or NO LOAD. What I did notice is that when first started there is the normal run time with no voltage, then the meter responds at about 105 volts for about 20 seconds, when the Heart Interface kicks in it then jumps to 150 and stays there. The Interface panel reads 14 volts @ 40 to 50 amps DC. I did accidentally shut down the Gen whie bothAC units and the water heater where on. I did not notice the voltage level before I did this. It was only when I restarted the Gen to see if there was a oroblem due to my shutdown error that I discovered this high voltage, even under load. I appreciate any insight anyone may have on this issue. The Heart Interface is a Freedom model 20. The Coach is a 1997 Gulf Strem Friendship 102. Thanks

[Mutha]

David, you need to have your Genset RPM and Hertz (60HZ) checked by a shop equiped to set these two parameters correctly. The higher the RPM The HIGHER the VOLTS and Hz.; This can burn up a lot of electrical stuff on your coach.

Let us know the final resolution and good luck in getting it solved.

Glenn

[David Selby]

Thanks Glenn, I'll be calling Cummins in the morning. I was hoping there might be a simple solution but I guss not.

[Mutha]

David, the Cummins folks generally know their stuff and in the long run they will save you time, money, and equipment - you are doing the right thing!

Best to ya, Glenn

[hamdave]

I had a similar situation with a kohler confidant genset. I looked at the drawing schematic/wiring diagram and found that there were three pot's(potentiometers) behind the genset control panel. I adjusted the voltage down and noticed the genset slow down a little as well. I'm a little off on frequency, but its within parameters necessary for the A/C. I have to get a freq-meter and then adjust both again. Cheaper than going to a shop. JMO

[SEMO Mike]

I had the exact problem with my Onan. I took it in and they said the rings were extremely dirty and the voltage regulator was checked. Not a big cost.