Twin plugs on OEM 110v trickle charger

[fooljoe]

Got it off ebay - on the cheep! Yes, I thought I'd need 2 of 'em as well ... until some of the friendly folks in the know, right here on mnl said you could wire one to do the job. My electronics engineering father in law said it's not possible . . . but the electronics engineering uncle of my wife agreed with Mnl folks who said it is possible to spoof 2 gfi's w/ one transformer. He helped me through the wiring so... now I'm good to go ... 1/2 the cost and 1/2 the weight !!

Can you post the details of exactly what to look for on ebay or otherwise and how to wire it? I've searched MNL and the rest of the internet exhaustively but can't find a complete answer to this. Thanks.

 

[ebill3]

Got it off ebay - on the cheep! Yes, I thought I'd need 2 of 'em as well ... until some of the friendly folks in the know, right here on mnl said you could wire one to do the job. My electronics engineering father in law said it's not possible . . . but the electronics engineering uncle of my wife agreed with Mnl folks who said it is possible to spoof 2 gfi's w/ one transformer. He helped me through the wiring so... now I'm good to go ... 1/2 the cost and 1/2 the weight !!

Can you post the details of exactly what to look for on ebay or otherwise and how to wire it? I've searched MNL and the rest of the internet exhaustively but can't find a complete answer to this. Thanks.

+1

Could you post the connection details?

 

[Ingineer]

If you use a 1:1 isolation transformer (rated for at least half the total wattage of your EVSE), this will work with it in series with outlet #2. For Safety, You should add the backfeed prevention relays as in the "Easy240" plans I posted awhile ago. In other words, use hot+neutral from one outlet, with hot+neutral in series with the isolation trans. For convenience, you can use a non-polarized 2 pin plug on one side so you can simply reverse the plug if you are 180 degrees out-of-phase. (indicator will reveal this) You could also use a DPDT switch, but the plug method is probably less loss and easy.

Be absolutely sure the transformer is rated for 1.5kW (for 12a EVSE) or 2kW (for 16a).

Also, we can program your EVSE to any amperage you desire. Just order the Rev2 upgrade and let us know your desired amperage. For instance, we could compromise with 14A instead of 12A.

As always, if you are not qualified, DO NOT ATTEMPT.

-Phil

 

[dcxplant]

...head expody head explody......

I didn't realize one had to be so smart to have this car!

Seriously great info, thanks.

So, Ingineer, this would still require two separate 110v lines/circuits, or just another outlet on the same line/circuit?

 

[fooljoe]

...head expody head explody......

I didn't realize one had to be so smart to have this car!

Seriously great info, thanks.

So, Ingineer, this would still require two separate 110v lines/circuits, or just another outlet on the same line/circuit?

Haha, sorry dcx, we kind of went off on a tangent there. You'd still need 2 circuits for the transformer method, it's just to get around the limitation of the circuits having to be on separate legs and non-GFCI. You can't get around the fact that one 120v circuit at 20 amps can only provide ~2 kw power, and you need ~4kw for L2, 240v charging.

 

[Ingineer]

Basically, if you were to plug a Rev2 into the same 120v circuit, like this (accidentally), it would attempt to pull probably around 34 amps from the 20 amp circuit. Of course this would near instantly trip your breaker.

Personally, I wouldn't advise anyone bother. I've always had good luck locating outlets elsewhere, and this saves on the expensive and heavy transformer. The only way I'd recommend it is if you are really a serious opportunity charger. (Like maybe trying to drive cross-country or something)

-Phil

 

[hill]

Basically, if you were to plug a Rev2 into the same 120v circuit, like this (accidentally), it would attempt to pull probably around 34 amps from the 20 amp circuit. Of course this would near instantly trip your breaker.

Personally, I wouldn't advise anyone bother. I've always had good luck locating outlets elsewhere, and this saves on the expensive and heavy transformer. The only way I'd recommend it is if you are really a serious opportunity charger. (Like maybe trying to drive cross-country or something)

-Phil

maybe around your area there are less outdoor GFI's. Most of the building in South Orange County Was done post 1975 ... And it seems like GFI's are everywhere. That said here was 1 of the helpful links that got me through the GFI spoofing project;
http://minie458.blogspot.com/2012_03_01_archive.html" onclick="window.open(this.href);return false;
Don't ask me why he took the cover off his ISO transformer - It doesn't decrease weight or bulk that much ... And it increases the ugly Factor.
Of course the usual caveat here . . . If you don't know what you're doing electrically - you will kill yourself. Even careless people who know what they're doing killed their self . As fun and handy as this project is - you are effectively defeating an electrical safety device.

 

[Ingineer]

maybe around your area there are less outdoor GFI's. Most of the building in South Orange County Was done post 1975 ... And it seems like GFI's are everywhere.

I usually try to find indoor outlets. It's been very easy to find someone's laundry room and/or kitchen that will have non-GFI outlets which will support 16A. In commercial places, most people are surprisingly open to letting you plug in if you ask the right person the right way. Most independent car service shops are interested in talking about EV's/Hybrids which I know a lot about, so after establishing a dialog, they'll usually let me plug in. Most already have 240v outlets too!

-Phil