I may have made an idiotic assumption regarding 220V wiring.

[Joyride]

I recently moved from Orange County to San Diego and the buyers of my old house didn't want my Leviton 40amp EVSE. When I bought my RAV4, I used the Toyota recommended process, electrician, and charger, and my EVSE was hardwired into my house's electrical system on its own 50amp curcuit.

When I moved to San Diego, I decided that instead of paying an electrician to wire my car charger into the new house, I would instead pay to have a 220V receptacle installed on the exterior of my house. Without doing proper research, I asked the electrician installing PV panels on my house to wire up an external 220V RV connector. He asked if I wanted 50Amps, and I said yes, because the Leviton charger needs a 50amp circuit. This is the connector he installed: http://www.homedepot.com/p/GE-50-Amp-Temporary-RV-Power-Outlet-U054P/100193650

Well, I unpacked my EVSE from its box in the garage and was surprised to find that it only has three wires (red, black, green) inside. The outlet I have has four connectors which I believe are 1xGround, 1xCommon, 2xHot.

So, does anyone have any suggestions to fix this mistake? I'm feeling a bit of the idiot right now for not doing enough research on this, so any suggestions are appreciated.

Thanks in advance,
-Chris

 

[Joyride]

As you can imagine, I've been doing some additional research and it may not be all that bad after all.

220V connections use three wires:
1xGround
2xHot

However, sometimes the thing being connected has both 220V and 110V components (such as a dryer or RV), so the 4 wire connection also includes a Common line that the 110V components within the device use for power (light bulb in your dryer), and the 220V components just use the two hots and the ground.

So, it looks like I can just wire up the 2 hots and the ground in my plug, and pretty much just ignore the Common for this application.

Any electricians or experienced folks think this is a good/bad idea?

Thanks!
-Chris

 

[TonyWilliams]

Your "common" is a neutral. You don't need it for 240 volts.

 

[4EVEREV]

As you can imagine, I've been doing some additional research and it may not be all that bad after all.

220V connections use three wires:
1xGround
2xHot

However, sometimes the thing being connected has both 220V and 110V components (such as a dryer or RV), so the 4 wire connection also includes a Common line that the 110V components within the device use for power (light bulb in your dryer), and the 220V components just use the two hots and the ground.

So, it looks like I can just wire up the 2 hots and the ground in my plug, and pretty much just ignore the Common for this application.

Any electricians or experienced folks think this is a good/bad idea?

Thanks!
-Chris

Please note, residential power in the USA is 240V and has been for a very long time, there is no 220V for US residential. 220 comes from the old days of 110V which we do not have anymore as well. In this application the neutral is simply a bonus wire.

 

[michael]

It is as you concluded. The fourth wire (usually white) is neutral and is used to support appliances that need both 220 and 110.

I like to use the term "220" because while residential wiring is usually 240 nominal, commercial and industrial wiring is usually 208 nominal. So I use the generalized term "220" to refer to both.

And yes, residential is nominally 120, but 220/110 makes descriptive sense as a generalized term even though it's not rigorously correct.

The more correct terms would be 240/208 for hot-to-hot, and 120 for hot to neutral.

 

[Incredulocious]

I usually use the term "220"...

"Yeah, 220... 221. Whatever it takes."

http://youtu.be/iX3kxAA2L4Q

 

[GlennD]

If you are in OC near Disneyland I have a spare 14-50 plug you can have for free. I certainly will not deliver it to SD. It was a TRW swap meet find and I think I paid $3 for it.

 

[smkettner]

I thought outdoor EVSE had to be hardwired to meet code.
Inspection will tell.

 

[GlennD]

According to your Amazon link only the hard wired version is weatherproof for outside use. The plug version is for indoor use such as a garage wall.

I think the cleanest fix is to replace the existing cord with a short 4 wire 50A range cord. That gets you a nice molded plug instead of the clunky add on plug. That is really why I have it on hand.

With a little searching a cable from Amazon is around $15. The second choice is to replace the socket to match the EVSE ignoring and taping up the unused neutral.

Correction, the link was from the original poster.

 

[4EVEREV]

It is as you concluded. The fourth wire (usually white) is neutral and is used to support appliances that need both 220 and 110.

I like to use the term "220" because while residential wiring is usually 240 nominal, commercial and industrial wiring is usually 208 nominal. So I use the generalized term "220" to refer to both.

And yes, residential is nominally 120, but 220/110 makes descriptive sense as a generalized term even though it's not rigorously correct.

The more correct terms would be 240/208 for hot-to-hot, and 120 for hot to neutral.

This is why people are often confused because of the wrong terminology they hear and repeat. 220/110 makes no descriptive sense as it is flat out incorrect for US residential and only reinforces confusion and ignorance of standards and specs and bad habits. Japan has 200V, not 210, 220 or even 240V and describing it as anything else does not make it easier for example. Commercial power is also different and the voltages have a basis and specifics do mater, that is why we have various voltages not a blended average. It puzzles me why people insist on using VERY outdated and incorrect terms. I constantly hear inexperienced electricians say 120 / 220 as if you dropped 20V someplace. You will never hear a properly qualified professional electrician say 110/240V or 220 for that matter.

 

[rickrides]

The 240V to my house is usually 238 but sometimes it's 250 (I glance at it often to see how my solar is doing). I guess there's an allowable range of voltage that PG&E can supply. When they up the voltage, they up the wattage on a resistive load.

 

[user 340]

I thought outdoor EVSE had to be hardwired to meet code.
Inspection will tell.

I have a Leviton 40A EVSE with a 14-50 plug that I installed outside with a permit and it passed inspection here in San Mateo County. The outlet has a "wetherproof" cover.

 

[TonyWilliams]

The 240V to my house is usually 238 but sometimes it's 250 (I glance at it often to see how my solar is doing). I guess there's an allowable range of voltage that PG&E can supply. When they up the voltage, they up the wattage on a resistive load.

The limit is normally 10% variation... 240 volts, up to 264 volts.