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  • Kohler 20kw Gen would not put out voltage…

    Posted by Dorel on October 11, 2017 at 12:08 pm

    Lately, our Kohler 20kw Gen would not put out the voltage required by the Inverters to start charging the batteries unless runs for awhile / gets hot…

    Scenarios:

    1. Autogen ON:

    When batteries are at Low voltage cut out set in the controlling inverter, signal is sent to Autogen to start, Autogen starts – no problem, runs but seems to fail to produce the required 117/118V to handshake with the inverters.

    Looking at Trace monitoring displays “Meters” screen:

    Inverters are inverting showing 118/121V – Green light, on both inverters, AC2 in is blinking once per second, some times goes into bulk charge for couple seconds, then returns into blinking mode AC2 in…

    AC2 “IN” display – shows the voltage scrolling between 105 to 125V or so, up/down, with only some times showing 117 or 118, then back to scrolling…

    Frequency is at 59/60 HZ on both inverters.

    Marathon dash display:

    – for Inverters, show same values as on Trace display, 118 / 121V

    – for GEN Power – one leg shows AC 121 V, the other AC 125V(goes up / down couple volts)

    As per Trace setup, if AutoGen fails to “handshake” with the Inverters at required voltage and Frequency within 10 min of autostart, Gen shuts off…with “Gen Sync” error displayed on the Trace Error cause display.

    Not sure why Marathon reports “constant” voltage values and Trace is scrolling between 105 to 125V or so…

    2. Generator ON

    Same values scrolling / reporting with the exception that the Generator is forced into “ON” run, is NOT required to complete the “handshake” for voltage or frequency with the inverters, just runs…after approx 1/2 hr of running, it start charging, and charge the batteries to float condition…but I will have to monitor the charge by driving to the storage few times per day…

    BTW, gen is maintained regularly, oil change – oil/fuel/air filters and belt changes.

    Another thing…sometimes while gen is running, it shakes then returns to normal run

    Looking for PC expertise on resolving these scenarios, where do I start?

    Thank you!

    Dick replied 8 years, 11 months ago 5 Members · 4 Replies
  • 4 Replies
  • Per

    Member
    October 11, 2017 at 2:48 pm

    Are those trace 4024 inv?

  • Will

    Member
    October 11, 2017 at 3:19 pm

    Yes Jeff..they are SW4024, one dated 2000 and the other 2004…

  • Dick

    Member
    October 12, 2017 at 12:25 pm

    My Kohler is the same vintage as yours and, while I am a poor electrician and not familiar with your vintage Marathon protocols, I will say that I chased a problem on mine causing intermittent shutdown for quite a while. Finally figured out that the problem was erratic voltage output from gen due to defective voltage regulator. Wondering if erratic output voltage may be an issue for you. the replacement voltage regulator failed about a year ago allowing runaway high voltage which I luckily noticed.

    BTW, my gen is currently down with burned wiring in the control box.

  • Tim

    Member
    October 12, 2017 at 8:50 pm

    Jeff, what are your thoughts?

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