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hedchange's avatar
hedchange
Explorer
May 18, 2015

Generac Impact-34 Plus Problems

I have recently acquired a Generac Impact-34 plus LP generator (Model 0941-1)
I wanted to install it in my Prowler 27 5A. This was just the right size to fit into the front compartment with a few modifications.

I had to rewire the 9 pin plug and the 2 pin plug that goes from the generator to the inverter. Upon completing this and testing the inverter with a static test. (Test 31 in the Manual - Everything tested within spec). This test was completed because the information that I got was the it stopped making AC power. I hooked up everything out side of the trailer and I was getting 120V AC out of the inverter. Running a skilsaw and a few other things to do a load test. This passed with several restarts there after and continued testing.

After completing the mods to the compartment and wiring in a ATS for the shoreline and the GEN i started the generator. After about 45 seconds the generator shut off. I assumed that it was because the 9 pin plug was broken but I did not have time to test it.

I retested the plug and continuity checked out fine.
I rechecked the inverter and everything was fine.

After turning on the generator and testing the inverter on the DC side i assumed that there was no power coming out of the output side. This was not the case. I checked the neutral and hot wire and was getting 22.0v AC. The inverter fans were not running and the inverter was humming. The side of the output gets really hot and I believe that this is why the generator turns off because the inverter senses over temp.



So after that long winded explanation up to now I have a few questions and hopefully you guys can help me answer them.

1: What controls the voltage that the inverter puts out
Is it the amount of DC voltage going in? (I did not remember what these values are)

2: Why would the inverter output 220V?

3: Could this be a control board problem?

Whatever information you could help provide it would be greatly appreciated. Thanks again

6 Replies

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  • hedchange's avatar
    hedchange
    Explorer
    May 25, 2015
    Ok quick update. I dug into the generator (good thing the box is big enough to get into the top without removing it). I found the circuit board and unplugged the connection to the diodes to check. Everything looked ok. While I was in there I actually took off and reseated all the connections several times. Went back into the trailer with the breakers off and noticed the fan was running I. The inverter. Turned on the circuit breaker and am now getting 120v. Plan is to get in there tomorrow and clean the terminals as much as possible and stick DG into all the connectors so the line don't oxidize or build corrosion . Thanks for the support and having a place to voice concerns and get problems fixed.
  • hedchange's avatar
    hedchange
    Explorer
    May 24, 2015
    Ok no new information today but I do have some questions and concerns.
    My dog was in the front yard today and ran out in the street under the gate because some horses went by. I took the gates off and was welding on them and got me thinking. The inverter 120V side was connected to an ATS and the DC in side were not connected to anything when I was welding the frame work in for the generator to sit on. Could this have caused and issue with the inverter. It was on the GEN side so the only thing that was physically connected in the ATS was the ground. If this is the case and the inverter is messed up why are none of my other electronics messed up. Everything works 120VAC and 12VDC that was connected when i was doing this.

    Secondly does anyone know anywhere in Southern California that will test the inverter if i take it too them. The local shops around me only have the ability to test Onan inverters. I am going to make a few more calls on Tuesday after the holiday.

    Thanks for your time.
  • hedchange's avatar
    hedchange
    Explorer
    May 22, 2015
    Checked the ats and it is not functioning. I ham going to return it under warranty and wire the shore power back into the control panel. Still working on coming up with a plan to check.
    Going to double check the polarity on the dc link again as I did not take note the first time I checked. I only looked at the output which the absolute number was in spec,
    Going to check the pcb. I should be able to get to the top without removing the generator as there is a good six inches above the unit.
    Thanks again for any input.

    EDIT: the polarities were good and they were the correct voltage
  • hedchange's avatar
    hedchange
    Explorer
    May 22, 2015
    Thanks for the advice. I have asked a mod to move it to the tech issues forum.

    I was reading another forum where a guy had intermittent no ac AC issues. Upon review I am going to be opening up the generator and fiddling with the connections on the PCB to see if that does anything.
    Also going to double check my ATS to see if there is anything in there that could be wrong even though the inverter only puts out 20V AC even when its unconnected.

    Just need to keep going. Reminds me of the issues I had on my honda when i first bought it. Ended up being the controller for ignition which is untestable :/

    Thanks again for your support.
  • Dtank's avatar
    Dtank
    Explorer
    May 22, 2015
    HC - (IMO) the best forum (here) for your question/s is the

    *Tech Issues* forum....that's where the generator gurus live, and not all of 'em,
    will visit the 5th wheel forum (lots of gens used for -or in- other types of RVs).

    You can simply ask the mod to move it.

    .
  • hedchange's avatar
    hedchange
    Explorer
    May 21, 2015
    Ok after some more testing.
    All the static inverter test were OK again
    Power supply test from the generator to the inverter was in spec for the circuit breaker off and on.
    The 9 wire testing with the generator on and circuit breaker on were all in spec.

    The DC voltage coming off of the red blue and black wires were all in spec.
    red-blue =375v
    black-red = 185V
    black- blue = 186V

    So I know that all the correct information is getting to the inverter but not sure if the control board is reading it in the generator.

    The inverter still only puts out 19-20v AC and the fan does not come

    -some background on the unit. This came from a camper that is owned by my grandfather. The generator has 78 hours on it and the inverter is new. When they bought the camper the generator had issues with supplying AC so they brought it to a shop and they said the inverter was bad. It was replaced. After being replaced it had worked for 2.5 hours and then it stopped.
    My grandfather tried to get it fixed again but the tech said it was not the inverter, that it was good.
    He took the generator out and replaced it with an onan. on.

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