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  • Generator Not Synching With Inverters

    Posted by Archived on February 5, 2017 at 8:31 am

    I am starting to experience a problem with the inverters when I start the generator. It does not happen every time but maybe every third or fourth time now. My coach is a 2003 Marathon with the Kohler 20kw genset and and the original two 4000 watt Trace inverters. The generator which has 6900 hours gets a lot of use compared to many on this site but I depend on it and maintain it frequently. Specifically, if I am watching the Tecklink system when I start the generator I can see it spool up. Normally after both legs reach 120 volts, the inverters will begin drawing current and you can see the amp draw on each beginning to rise after about 30 seconds. Recently after starting the generator, and a minute or so afterward, I could tell from the sound of it running that there was little to no load on it. Sure enough, the Techlink display verified there was no draw from the inverters. I walked back to the inverter panel and both “AC2 in” indicators were still flashing. After another minute, and no change, I put the first inverter in “Search” mode and the “AC2 in” LED almost immediately went solid. I returned the inverter status to “On” and did the same with the second inverter. Everything functioned normally after this.

    Several weeks later, and after other successful generator usages, the same scenario played out. Has anyone ever experienced this problem? Since both inverters are initially rejecting the generator power, my first guess is a problem with the transfer switch. Let me hear your all’s thoughts. Thanks.

    Archived replied 9 years, 8 months ago 7 Members · 16 Replies
  • 16 Replies
  • AL

    Member
    February 5, 2017 at 10:31 am

    Advice from me as a Liberty owner is essentially worthless, but unless Marathon does things completely different than a Liberty my guess of the issue has nothing to do with the inverters.

    I may have misunderstood, but am I right in assuming when the generator starts that circuits not run through the inverters are unpowered? I think you said generator power is not sensed by the inverters so they are not switching to function as chargers. If that is the case I would look first at the transfer switch that should be sensing the generator and allowing generator power to pass through to all 120V circuits.

    Do you have a similar issue with shore power? If not, to prove my theory you might be able to swap transfer switch relays and if that fixes the generator issue, it likely has moved the problem to the shore power relay.

    Keep in mind the above might be fertilizer because I am thinking of in terms of how my Liberty is set up.

  • Archived

    Member
    February 5, 2017 at 11:00 am

    Have you checked the circuit breaker on the front of the inverter? Had a problem with one of the inverters, and found the CB had tripped.

  • Archived

    Member
    February 5, 2017 at 12:43 pm

    You should have a square light in the main breaker panel inside bus labeled “AUX RESET” After you plug in to shore power, throw the breaker box to “on” allowing shore power into your bus. In my experience this light could flash a short time probably a minute or several minutes. In then stops flashing and allows the transfer switch to accept incoming shore power on 2 legs.

    If “AUX RESET” light remains on you have a problem with resets …gen to house or shore to house give Leon a call. My issue was the incoming power bus breaker switch.

    Another item Marathon owners should check and replace is the breaker / transfer switch you flip each time you accept or stop shore power to your bus. Brand is “Square D” and available at Home Depot under $10 bucks, carry a spare. They wear out from use.

    AL

  • Archived

    Member
    February 5, 2017 at 2:46 pm

    I’m having zero problems on the shore power side of the equation. That main breaker is relatively new. My aux power light functions as it always has when shope power comes on line. I will certainly check breakers on the actual inverter boxes as well. I will also do a little research on the transfer switch relays as suggested. Keep the ideas coming. This has not been a problem that is stopping us from using the coach, it just is not behaving as it has for the past 10 years.

  • Roy

    Member
    February 5, 2017 at 3:22 pm

    Towson,

    If you aren’t having problems with shore power you reinforce my opinion (as a Liberty owner) the issue is isolated to the transfer switch. If I am right and all these Marathon guys are wrong I am going to do a happy dance, but if they are right does anyone know where I can get a decent size crow for dinner?

  • Archived

    Member
    February 5, 2017 at 4:14 pm

    I would’nt be lick’en my chops…. not yet…Mr Knoxville

  • John

    Member
    February 5, 2017 at 9:17 pm

    I’ll wait for the report from Towson. I do not particularly enjoy eating crow so I am not licking my chops Mr. Marathon.

    (Mr. Marathon is Al’s new name and unless he wishes to elaborate I will leave it at that. It has nothing to do with this thread.)

  • Archived

    Member
    February 5, 2017 at 10:51 pm

    Al,

    Breaker switch that Marathon owners should be switching when they accept shore power?

    Add one more thing to the list of things I have not learned yet about our coach.

    Hopefully, I can get some of the orientation we never got from our private sale at the Carlisle Rally this month.

    Thanks for always providing such great info in your posts.

    Jon and Tom, Al’s dues for next year are on me.

    Love this group.

  • Larry & Diane

    Member
    February 6, 2017 at 8:27 am

    Tranfer switch……

  • Archived

    Member
    February 6, 2017 at 2:17 pm

    So where is the transfer switch located on a Marathon?

    I’ve looked but darned if I can locate it on my coach.

  • jack

    Member
    February 6, 2017 at 5:08 pm


    On our coach is on driver side, 2nd bay on the forward wall.

  • Archived

    Member
    February 6, 2017 at 5:59 pm

    Its a breaker located by the buddy recepticle , I leave mine on all the time.

  • Archived

    Member
    February 6, 2017 at 6:55 pm

    John,

    Al’s right on!

    I replaced my “Square D” breaker last February while sitting at the Air & Car Show. Switched out my five led lights as well since mine were all so dim I couldn’t tell if they were working or not. Easy fix, under an hour, at minimal price.

  • Archived

    Member
    February 6, 2017 at 7:55 pm

    Just to clerify, the breaker Al and Tim are talking about is for shore power and has nothing to do with the generator or it’s power supply.

  • Peter

    Member
    February 6, 2017 at 9:46 pm

    Apples and oranges Tim. I will wait for Towson to report, but until then I have to stick with my educated guess.

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