Forum Discussion

roachcoach's avatar
roachcoach
Explorer
Oct 01, 2015

UPS

I purchased 2 APC UPS battery backup to keep the receivers on and not have to reboot constantly. It's working great on shore power but when I plug into the inverter the building wiring fault light comes on. The inverter is working as it always has. The people at APC say the inverter needs to be grounded, well it is grounded so not sure what they mean?. They said the ups will work even with the building wire fault on but if it won't be covered under warranty if it malfunctions.
Hoping someone can shed some light on this

Double post
See other thread running
Thanks

Admin
RV. Net
Class A

4 Replies

  • chuckbear's avatar
    chuckbear
    Explorer
    Oct 01, 2015
    UPS devices have issues running on inverters. But I don't see the need to run a UPS on an inverter since they basically do the same thing.
  • DrewE's avatar
    DrewE
    Explorer III
    Oct 01, 2015
    I would guess that the neutral and "ground" are not bonded by the inverter.

    It's possible that you could fiddle with e.g. the transfer switch setup for the inverter to bond them when using the inverter (and only when using the inverter). However, it's also at least theoretically possible that the inverter would not work with its neutral output bonded to ground with some output circuit designs. You'd have to consult the inverter maker.

    I personally wouldn't worry too much about the light. My guess is that in practice either they would cover any reasonable fault under warranty and have the disclaimer for the odd situation where the building wiring is dangerously faulty, or else they would try to avoid warranty coverage for using the UPS with an inverter in the first place, apparent wiring fault or not.
  • ILVMYGT's avatar
    ILVMYGT
    Explorer
    Oct 01, 2015
    Do you have a modified sine wave inverter? Modified sine wave inverter can cause interesting issues with some equipment.

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