230 vac inverter to house breaker box – weird things happened

  • 230 vac inverter to house breaker box – weird things happened

    Posted by coyotech on June 7, 2023 at 4:34 am

    I helped a friend put a new 230 vac 48 v 5Kw, pure sine inverter in today. It goes to his house breaker box. Previously he had a 120 vac 48v 5kw inverter which couldn’t run his 220 appliances, but did fine with the regular circuits. He’s gone off-grid on an all electric house. He especially missed having hot water, as the 220v water heater could barely warm any water, or none at all.

    So we got this new inverter which I went to help install today. It has 3 AC output terminals: 2 hots and a ground, or one marked ground. Of course the box needs 2 hot wires, and I thought a neutral … for 110. But there is none. I researched a little where it said 230 vac didn’t need a neutral. So I used the white wire as a hot, the black, and then the copper as the ground, and nothing to the neutral bar. It was 2 wire romex. Well, when we turned it on, several light bulbs and things popped and the ceiling fan started smoking! Turned off the ceiling fan, and found that most of the surviving regular lights and circuits worked, but some didn’t. The 220 things did work. The problem was in the regular 110 circuits. But then after awhile, nothing worked. The inverter had no error messages and seemed to think it was fine, but the fan quit running and nothing in the house was going. He said the inverter (judging by the fan) just gradually wound down. No error messages. I turned the switch on and off, disconnected and reconnected the positive cable from the batteries, turned breakers on an off … nothing.

    So we disonnected the new inverter and put the old inverter back in. The TV and computer are dead.

    Does anybody know what we did wrong, what we should do different? I’m going back tomorrow … but it’s still a mystery to me.

    Tomorrow I’m going to bring some heavier romex for the connection between the inverter and the box, since this inverter will accept bigger wire, and the old wire seemed too light for this set up, and was running warm. Could that have been the main problem? While I recognize using wire that’s too light is dangerous, I didn’t think it would cause the problem we ran into.

    waynenorman55 replied 5 months, 3 weeks ago 4 Members · 4 Replies
  • 4 Replies
  • CarolinaCarefree

    June 7, 2023 at 5:41 am

    The smaller wiring may have been the issue, but I would worry more of it being a fire hazard. The inverter should have recommended a wire size. I would go with it. Also when connecting it up, (since you are using the white as hot) do not (again do not) connect the white to the neutral (other whites) in the box, as this will send voltage backward on the other circuits and burn everything up. If the white is hot from the inverter it should act as a second main going into the box. Also turn all breakers off, once the inverter is in then turn your circuits on one at a time. This will help.prevent over loading and causing a surge from the inverter. Hope this helps. It is hard to say without being there. By the way, I am not an electrician, but have at times work with power. You may want to check with an electrician.

    • CarolinaCarefree

      June 7, 2023 at 6:13 am

      One more thing, for future reference to anyone else working on this system, please mark the white (if hot) with red electrical tape, on both ends. This will allow someone to know it is hot and not neutral. Hope some of this helps.

  • PaulAtreides

    June 7, 2023 at 3:05 pm

    When hooking up any new source of power I check and triple check the voltage before I add it to a circuit. I got an inexpensive ocillisope off of Amazon and it will do voltage and give you sinewave readings.

    Like cutting material, measure twice or three times cut once. Also when hooking anything sensitive that is electronic in nature I always put a UPS if there is any remote doubt as to the votage or sine wave even if I’ve tested. Cheaper to fry a UPS than your electronics. Always say to myself if I can’t afford to lose it, sepecially in SHTF make no assumptions before I hook something up.

    Your PC may just be a fried power supply and that is esily and inexpensively replaced. The TV may have the same issue but the power supply may not be inexpensively or easily replaceable. Also Check for fuses either clipped or sodlerd to the circuit boards of both devices.

    Side Note: I have a couple of freezers that do not like the modified sign wave from my 5kw generator and will not run but I put a UPS (because I have a bunch of old ones lying around) between the power and the device and it gives a clean sine wave and they are happy.

  • waynenorman55

    December 2, 2023 at 7:56 pm

    If your going to run both 120v lines and 220 your going to need an inverter that is a split phase with 2 120 lines.

Log in to reply.