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exp2ex's avatar
exp2ex
Explorer
Jun 30, 2016

Converter Toubleshooting Question

My Converter - WFO WF-8955AN
Here is a video of my problem. Little long because of the gremlins in the box !

https://youtu.be/mdQOuhGCluQ

Trying to troubleshoot my issue.
Got a new battery and hooked it up to the camper.
Took the panel cover off the converter.

Put a 12v test light on the 12v feed line and the 12 neg line on the converter.
Test light was very dim. approx. 25% compared to when I put it on the battery prior to connecting the cables.
I start switching all the AC breakers one at a time to see if there is any change in the light on the tester.
Sure enough, the main (30amp) breaker causes a noise and the tester goes to very bright for a moment then goes back to being dim.

19 Replies

  • Quick update.

    I pulled the converter and just set it in front of the opening on the floor.
    Plugged the 220 line in and put the positive lines on the battery.

    Everything seems to work in this configuration which leads me to believe that there is a loose wire somewhere. So I unplugged the 220 line and removed the + cables off the battery. I tightened all the lugs on the ground bars, breakers, and 12 v circuits.

    All appliances and circuits appear to be working as designed. I turned everything off but left the fridge on to see if it cools down. Previously the check light would come on a few minutes after I pressed it.
    We will see how that works out.

    Also, I checked the voltage at the battery and the - / + terminals in the converter. Both Read 12.57 V. The NEW battery might have had some drainage from last week prior to me removing the cables. So I will check it later tonight.

    So I hope the problem is resolved !

    Thanks to all the input.
  • Alright !
    Great info folks and for that I say thank you !

    I will do some more work on this today and follow up with what I find out.

    Thanks again.
  • https://youtu.be/mdQOuhGCluQ

    OK so I watched the video. Looks like an intermittent 12 volt connection issue. Because it affects several systems (12v thermostat and 12v lights) I believe it is a common ground point issue. So pull the last four screws and pull the whole power center out from the cabinet. Behind you should find a common ground bus. Tighten all connections. Then follow the main ground where a big wire drops through the floor and connects to the frame. Clean and tighten that connection to the frame.

    At some point you stepped hard on the floor and the lights flickered. If you really want to find the issue you might be able to gently wiggle those ground connections and see the lights flicker.
  • alaska dennis wrote:
    Where does the green wire go that is attached to the positive terminal? I am wondering why two plus connections.


    Is it fused? Power jack, maybe?
  • Where does the green wire go that is attached to the positive terminal? I am wondering why two plus connections.
  • wa8yxm's avatar
    wa8yxm
    Explorer III
    I too suggest Progressive Dynamics over WFCO.. In fact in doing considerable research I have yet to find a converter I like better than the Progressive Dynamics with the optional dongle or optional wizard depending on the model.

    And I doubt I ever will


    Alas there are many reasons you may be getting low output voltage. Some converters really do not play nice without a battery attched.. My 9180 (progressive dynamics with added wizard) plays very nice without a battery.
  • exp2ex wrote:
    My Converter - WFO WF-8955AN
    That is plenty of information right there to recommend a replacement with a different brand.

    I recommend Progressive Dynamics or IOTA. Possibly PowerMax if you are always plugged in.
  • Use a voltmeter

    Measure Converter DC output

    With 120V AC input to converter.......DC output s/b 13.2V DC MINIMUM

    Anything less and converter has failed


    Which is what you dimming suggests

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