Forum Discussion

d-mac1's avatar
d-mac1
Explorer
Apr 13, 2015

Boondocking - power transfer switch (DC to AC ) quit working

We were under generator power last night when the removable key to the battery disconnect switch vibrated out and afterwards, the auto transfer switch (that switches trailer to AC power) will not work. Am boondocking and would like AC power. Any ideas? Seems like the transfer switch needs a reset...I find no button to do so on the switch housing.

Anyone know if generator will charge batteries if transfer switch inoperable?

Sequence of events was this...key to disconnect switch must have gotten bumped when unloading stuff cuz the lights were flickering right before they went out when we were under AC (generator) power. I found the key switch was out and reinstalled and we have DC power but the transfer switch wont switch us to generator. The breakers at the generator were not tripped. I reset them anyway. I tried removing DC power via disconnecting batteries briefly to see if that would reset transfer switch, no go.

Any ideas? If I pop the cover off the transfer switch, anything servicable in there? I have volt/ohm meter.

Thanks for any help!
  • d-mac1's avatar
    d-mac1
    Explorer
    Apr 13, 2015
    Only things running when this happened was tv, dvd player a couple lights and 2 cell phone chargers. How would I test inverter?
  • d-mac1's avatar
    d-mac1
    Explorer
    Apr 13, 2015
    Will pop the lid off in a while. If the transfer switch doesnt switch between dc and ac, what does? When I am on dc power and start genny, after a 15 or so sec delay, there is a noticable click, almost a pop, and ac power is functional. Thats what normally takes place. No switch over now.

    Isnt the transfer switch doing the change?
  • TT_Tim's avatar
    TT_Tim
    Explorer
    Apr 13, 2015
    Yes, pop the cover off the transfer switch, make sure there is AC power coming in from the generator, then check the output. If nothing, could be a bad coil on the relay.
  • Me_Again's avatar
    Me_Again
    Explorer III
    Apr 13, 2015
    "lights were flickering right before they went out" That is not a good sign! Maybe your converter got fried. What do you measure for DC voltage in the trailer? Did you have a heavy AC load when this happen? Air Conditioner running etc.

    Sounds like a bad AC connection, maybe at the transfer switch.

    Chris
  • RoyB's avatar
    RoyB
    Explorer II
    Apr 13, 2015
    Having a MULTIMETER around is very helpful determining if your batteries are charging.

    I use my MULTIMETER all the time across the battery terminals to check their DC VOLT level. If they are 'fully charged' I see from 12.6-7VDC when my trailer is not connected to the shore power or AC Generator. When I connect to shore power or attach a Generator the DC VOLT LEVEL will jump up to 13.6VDC or higher telling me the battery is charging. Same thing should happen for your batteries.
  • Ivylog's avatar
    Ivylog
    Explorer III
    Apr 13, 2015
    No you are not going to charge your batteries until you get AC power inside the rig. It concerns me that you posted (DC to AC) as a transfer switch does not do that... it switches the AC between shore and generator.
    Sounds like the coil that holds that side of the contacts closed is not getting power. If you cannot find the problem (are you sure you have power from the generator), I'd figure out how to manually hold those contacts closed or run jumper wires around them, or bypass the transfer switch completely... for now.

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