I have a battery and an inverter. I just want to carry them into the house if there is a power outage. I am concerned about safety and earthing the inverter. Can I wire the inverter earth to a plug with only the earth wire connected, and plug it into the house AC circuit?
No I would not do that! It is not about the earthing, you need to disconnect the utility input in such a way should power be restored your inverter output is protected from the utility input, it is called a transfer switch( automatic or manual) where live ( hot) and neutral is isolated from the utility. The switch ensures that only 1 ac supply would be servicing your loads at any time.
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Thank you for taking the time to reply. I don’t understand. How would a restoration of the utility supply be a problem if only the earth pin in the plug is wired?
@kennethclements if your concerns are safety this is not a safe way the whole point of a back up system is everything is backed up.
I can only speak for UK side but a lot os our properties are TNC-S Terra Neutral Combined Separate this means the earth and neutral one cable and then separated at the DNO service head. Or a TNC which is the same but not separated.
Or you have a TT system or are blessed with TNS.
If your DNO neutral breaks known as PEN fault which is not uncommon at least in the UK which result in a lot higher voltages due to the neutral break but the other issue is that ever one earths there metal water and metal gas pipes so you may have no idea your neutral has gone as it’s using the earth to the pipes same as your neighbour so just jumps from the earth back to a part of the neutral that has not broken. Not just as simple as an earth rod in the ground as there is a lot more resistance which could cause RCD’s not to trip.
Get a Spark in to do the work, The DNO earth can not be relied on hope this helps
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Regulations normally require that an inverter earth is permanently connected. This does not allow plugging in an earth connection.
The appropriate way to do what you want would be to have an RCCB or ELCB on the inverter output, and that powers only one or 2 sockets on extension cables for appliances to be plugged into. no connection to fixed wiring would be permitted.
Thanks all. That makes sense, I saw a video about the PEN issue recently, I’ll put a RCCB on the output.