charging AC lines - off-grid cabin

bobdog

This sounds really dumb, but how do you all run your output from the inverter to the AC circuit panel?

I just looked and like my cheap one, the expensive inverters have "wall" plugs or receptacles as AC outs. So, I have a homemade cord with a male plug on one side, and open wires on the other. The male plug, plugs into the inverter and the open wires attach to the AC panel box and breakers, etc. Is this how everyone else does it?

Tim

niel

Re: charging AC lines

THIS IS NOT A DUMB QUESTION.
unless the inverter is meant to tie to the grid, DO NOT ATTEMPT TO CONNECT IT TO YOUR UTILITY AC! cheapo inverters are not meant to be grid tied. plug your stuff into the inverter, fine, but do not plug the inverter into your utility ac or nasty things will happen. at a minimum the inverter will be destroyed. this can be violently with the possibility of fire as well. this will also pose an electric shock hazard.

bobdog

Re: charging AC lines

I'm sorry, I didn't make myself clear. This is for an off-grid cabin.

The reason I'm asking is that I'm confused that someone would spend 100's if not a thousand dollars on an inverter and then have to use a homemade "extension" cord to plug the inverter into the AC distribution panel. It seems to me they would be "hard wired".

Sorry for the confusion, but I'm still wondering how it is done by the big boys.

Tim

niel

Re: charging AC lines - off-grid cabin

ok, the bare ends just get hardwired into the breaker/distribution panel with the other end just plugged into the inverter. some do provide for hardwiring, but many may wish to plug an appliance directly into the inverter and would then need to hardwire a receptacle just to do that. big reason is that it's easy for the manufacturers to just put a receptacle on it.

bobdog

Re: charging AC lines - off-grid cabin

Thanks Niel. I just wanted to make sure I was doing it right.

icarus

Re: charging AC lines - off-grid cabin

Bobdog,

Be advised however than many (most) cheap inverters will self destruct if you wire it into a panel box with a grounded neutral.

Make sure that the neutral is not bonded to the grounded bus bar in the panel. Cheap inverter use a floating neutral and will go up in smoke right now if grounded! I know this from painful experience.
Tony

bobdog

Re: charging AC lines - off-grid cabin

icarus wrote: »

Bobdog,

Be advised however than many (most) cheap inverters will self destruct if you wire it into a panel box with a grounded neutral.

Make sure that the neutral is not bonded to the grounded bus bar in the panel. Cheap inverter use a floating neutral and will go up in smoke right now if grounded! I know this from painful experience.
Tony

I was thinking that as well. Given that, I will probably use my Suresine when I get back up to the cabin. How do you have yours wired in? Is there a grounded neutral?

BB.

Re: charging AC lines - off-grid cabin

Always check the manual--But True Sine Wave inverters typically can have a grounded neutral (Sure Shine included). Typically, MSW (especially cheap MSW) cannot support a ground neutral.

And, specifically the grounding issue is if both the inverter output is bonded to a common ground AND the battery bank is also bonded to the common ground (commonly negative ground--but positive ground is also a problem).

For an MSW inverter without transformer isolation (transform isolation is expensive)--the common DC Input / Output grounding creates a short circuit through the inverter's internal switching FETs.

-Bill

icarus

Re: charging AC lines - off-grid cabin

I have my suresine wired with a grounded neutral,

Tonyu