Forum Discussion

Chuck_Sorensen's avatar
Jan 04, 2015

Generator Check using Portable Power Protection Unit

When running the Onan generator, I have used my portable power protection unit, a Progressive Industries 30 amp to see what it thinks of the generated power. Using a 30 amp female to 20 amp male plug I connect the protection unit to a van 120 vac outlet; a three wire extension cord helps. Nothing need be plugged into the protection unit. The error codes will show what the protection unit sees and the generator frequency and output voltage are displayed.

Chuck Sorensen
Buellton, California
2012 Ford PW Excel TS
  • Interesting. I also have a Progressive unit and an Onan generator. What did you find out with the test?
  • Good thread, I have a champion 4000 and plugged a surge gard into the 30 amp outlet.....get parttime flashing red light saying to use caution and reverse polarity read out for about 30 seconds, then get steady green light for about same time and reads correct voltage and amps....no reverse...all appliances in unit work fine.....it flips from one to the other during the whole operation no matter what kind of load....called surge gard and they say is normal because of a floating ground in all generators.....any thoughts from other users?
  • Also, if your rig has a fancy inverter/charger, it very likely is able to do a thorough analysis of the AC input (whether from shore power or genset). I know our Outback 2800 watt inverter does so. Explore the menus.
  • I use a fluke multimeter to check the frequency of the genny ac power- it is within a few cycles of 60 Hz all the time under various loads.
    Like the voltage it will swing slightly as the Onan 2800 responds to load.

    A more likely source of problems is shore power- easy to check with a plug in "checker" along with a voltmeter.

    Good practice to check before plugging in.


    this way you know what is happening, rather then using a "box".
    keeps money in your pocket too.

    Mike
  • jjson775 wrote:
    Interesting. I also have a Progressive unit and an Onan generator. What did you find out with the test?


    Hi -

    I found that the generator was wired correctly; at least to the receptacle that I plugged the Progressive unit into. No Power Protection alarms while running the generator under different loads.

    Chuck Sorensen
    2012 PW Excel TS
  • In the Transit build I'm working on, the generator feeds a Magnum Energy MSH4024RE inverter/converter that takes two 120VAC sources as well as batteries. It is $2319.20 on Amazon, and $2245.00 at Wholesale Solar, but it makes things like damaging voltage sags a thing of the past. Plus, it can be connected to a generator controller so it can automatically start a generator if the batteries hit a low water SoC mark, and stop the generator when the batteries hit a high water SoC level.

    The inverter isn't cheap, but it does allow for a generator to be a tad off with regards to voltage or frequency, and not affect anything else.