Tesla Charging Adapter & the BMW i3

Hello Everyone,

We are looking for a little help from the community on a problem a customer was looking to have resolved. Can a NEMA 6-50 to 14-50 Tesla charging adapter work with the BMW i3? (Example for reference:http://www.corddepot.com/shop/ev-products/nema-6-50p-14-50r-evse-adapter-cord/). This is in the U.S.

We are curious as to how BMW wires their chargers, and if there are any options for wiring / purchasing adapters for charging on different outlets.

A plug is a plug when you are talking about NEMA standards. There is only one correct way to wire it. Now if you are talking about making a Tesla specific EVSE work on an i3 there is no adapter for that (or any other car).

That looks like a 240V plug adapter for the US. In the US BMW only supplies a portable “occasional use” 120V EVSE. The BMW 240V EVSE is a permanent mount unit without a plug, I believe.

In the US if you want a portable 240V level 2 charger you’ll need to buy a third party EVSE. It would have a SAE J1772 connecter to plug into the i3 and something like a NEMA 14-30 or L6-30 to plug into the wall. Then a plug adapter to switch to another 240V socket type might come in handy.

If you’re talking about the European market I don’t know. Do they use NEMA plugs like that there?

This would be for the U.S. market, so I don't think we are worried about the Euro standard.

A plug is a plug when you are talking about NEMA standards. There is only one correct way to wire it.

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There is only one correct way I am aware. But as you may know, Tesla wires their Model S superchargers and adapters without a neutral.

So I guess what I'm asking is: Does BMW have a proprietary way of wiring their chargers / adapters, or is it wired the NEMA correct way as mentioned by jelloslug?

Corddepot said:

This would be for the U.S. market, so I don't think we are worried about the Euro standard.

A plug is a plug when you are talking about NEMA standards. There is only one correct way to wire it.

Click to expand...

There is only one correct way I am aware. But as you may know, Tesla wires their Model S superchargers and adapters without a neutral.

So I guess what I'm asking is: Does BMW have a proprietary way of wiring their chargers / adapters, or is it wired the NEMA correct way as mentioned by jelloslug?

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I have not seen a US spec level 2 EVSE that required a neutral. The BMW Wallbox Pure is made by Bosch.

Corddepot said:

Hello Everyone,

We are looking for a little help from the community on a problem a customer was looking to have resolved. Can a NEMA 6-50 to 14-50 Tesla charging adapter work with the BMW i3? (Example for reference:http://www.corddepot.com/shop/ev-products/nema-6-50p-14-50r-evse-adapter-cord/). This is in the U.S.

We are curious as to how BMW wires their chargers, and if there are any options for wiring / purchasing adapters for charging on different outlets.

Click to expand...

The BMW wall charger appears to be hard-wired: http://www.bmwusa.com/Standard/Content/Vehicles/2014/i3/BMWi3/360Electric/BMWiChargingStation.aspx

If your customer wants to charge an i3 from a variety of outlets, this and the appropriate adapters from Tesla should do the trick: http://shop.quickchargepower.com/JESLA-is-THE-40-amp-J1772-portable-charging-solution-JESLA.htm

But a more cost effective solution would simply be to get a standard EVSE that can be plugged into the desired outlet: http://www.clippercreek.com/store/featured-products/

I have a Model S and my wife just got an i3 and we're planning to get a clipper creek EVSE that plugs into a NEMA 14-50 outlet for the i3 so both the i3 and the Model S can charge from the same outlet (although unfortunately not at the same time).

jelloslug said:

Corddepot said:

This would be for the U.S. market, so I don't think we are worried about the Euro standard.

A plug is a plug when you are talking about NEMA standards. There is only one correct way to wire it.

Click to expand...

There is only one correct way I am aware. But as you may know, Tesla wires their Model S superchargers and adapters without a neutral.

So I guess what I'm asking is: Does BMW have a proprietary way of wiring their chargers / adapters, or is it wired the NEMA correct way as mentioned by jelloslug?

Click to expand...

I have not seen a US spec level 2 EVSE that required a neutral. The BMW Wallbox Pure is made by Bosch.

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Incorrect, the BMW Wallbox is made by Schneider Electric.

There are a few things to overcome. You will need a CAN to PLC translator. An analog handshake and pin adapter would have to be configured. Futhermore, you will need V2G and V2H support. This certainly isn't impossible, but as far as I know, no one has done it yet most likely due to proprietary implementations.

Corddepot said:

Can a NEMA 6-50 to 14-50 Tesla charging adapter work with the BMW i3? (Example for reference:http://www.corddepot.com/shop/ev-products/nema-6-50p-14-50r-evse-adapter-cord/).

We are curious as to how BMW wires their chargers, and if there are any options for wiring / purchasing adapters for charging on different outlets.

Click to expand...

I think perhaps the OP does not understand that these plug adapters handle power upstream of the EVSE, that the J1772 EVSE standard does not require a neutral, and that any J1772 compliant EVSE could not give a rat's ass about whether it gets its power hardwired from the CB (most inexpensive and reliable way to go), from a rather expensive and more complex pigtail plug into a socket (NEMA 6-50P to 6-50R, or NEMA 14-50R to 14-50R - doesn't matter), or a very expensive and convoluted chain of pigtail plug (NEMA 14-50p) to adapter (NEMA 14-50R to 6-50P) to wall socket (NEMA 6-50R)

Electrons is electrons. It's all good.

If you are installing a fixed EVSE, you can save a couple hundred bucks by simply hard wiring it to the breaker. If you absolutely need portability for a 240 volt EVSE, the smart approach would be to purchase an EVSE without any plug (i.e., the hardwired version) and fashion your own pigtail with exactly the plug that you need (unless you can get exactly what you need from Clipper Creek for fewer total dollars). You only need adapters if you need to plug in to multiple standards.

Sorry, but a neutral, or ground wire is required for a level 2 ESVE. You must be connected to a circuit that has 110v.--0--110v. that gives 220v. across the two hot leads. The ESVE logic searches for a grounded neutral during the handshake before it will allow the connection to the car charger. I found this out the hard way when I connected a hard wired Level 2 ESVE to my high rise garage 240v. circuit, which is a 0v.--240v. circuit (the building is a 480v. center-tapped wye distribution system to give single ended 240v. The distribution system then uses 240v to 120v.--0--120v. transformers to supply household electricity. Even though I connected the building electrical ground to the ground wire of the ESVE, the ESVE wouldn't recognize the connection. I had a long talk with Clipper Creek technical and they verified that US ESVE's require a ground between the two 110v. hot legs, from which the 220v. for the ESVE is derived. If you look at your home breaker boxes, you will see that your household electricity comes into your breaker box as 110v.--0--110v. down two alternating contacts in the breaker box. A 220v. twin breaker connects to the two sides with one hot wire each going to one of the twin breakers and the ground wire going to the neutral between the two sides.

ted99 said:

Sorry, but a neutral, or ground wire is required for a level 2 ESVE. You must be connected to a circuit that has 110v.--0--110v. that gives 220v. across the two hot leads. The ESVE logic searches for a grounded neutral during the handshake before it will allow the connection to the car charger. I found this out the hard way when I connected a hard wired Level 2 ESVE to my high rise garage 240v. circuit, which is a 0v.--240v. circuit (the building is a 480v. center-tapped wye distribution system to give single ended 240v. The distribution system then uses 240v to 120v.--0--120v. transformers to supply household electricity. Even though I connected the building electrical ground to the ground wire of the ESVE, the ESVE wouldn't recognize the connection. I had a long talk with Clipper Creek technical and they verified that US ESVE's require a ground between the two 110v. hot legs, from which the 220v. for the ESVE is derived. If you look at your home breaker boxes, you will see that your household electricity comes into your breaker box as 110v.--0--110v. down two alternating contacts in the breaker box. A 220v. twin breaker connects to the two sides with one hot wire each going to one of the twin breakers and the ground wire going to the neutral between the two sides.

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You are talking a totally different animal than normal household power. I had the same issue that you did when hooking up a CS-100 at work, no neutral in the system at all. In the end though there still is no physical connection from the neutral to the EVSE, it just has to be in the circuit for ground fault protection.

ted99 said:

Sorry, but a neutral, or ground wire is required for a level 2 ESVE.

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A ground wire is required. A neutral is not. They are not the same thing, and using one in place of the other can be hazardous.

Ground fault works by comparing the current on the two power leads...ground is NOT required in the circuit at all! On a 120vac circuit, one side is neutral, but on a 240vac circuit (split phase in the USA, different in Europe or places where 240vac is the norm), it still measures between the two power leads, in this case L1 and L2 - no neutral or ground is involved. It is only when the power in verses the return differ (typically in the 5mA range) that the GFCI circuit will trip, sensing that some of that current went someplace it shouldn't have (typically to a ground outside of the power system, and maybe through you) and shutting down to protect the innocent. In the USA, one very common thing to do on older houses where you don't want to rewire the house is to replace a receptacle without a ground with a GFCI. Perfectly legal to do, as long as you use one of the included stickers that says "NO GROUND, GFCI Protected" on any downstream.

The EVSE uses ground for safety of the box, but its power out to the vehicle could care less as long as the power out and return current are the same.

jadnashuanh said:

...ground is NOT required in the circuit at all!

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Not accurate according to installation instructions of every North American EVSE I have installed.

jadnashuanh said:

The EVSE uses ground for safety of the box, but its power out to the vehicle could care less as long as the power out and return current are the same.

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Which is why ground is required, and neutral is not. The J1772 standard requires comparison of the power out and power return, and incorporates GFCI logic in the EVSE itself to immediately cease current flow once they exceed a reasonable trip point (typically implemented as 20 or less milliamps - I do not have free access to the standard itself). Interestingly, at least one EVSE manufacturer recommends that you do not plug an EVSE in to a GFCI outlet, as the two comparison circuits might trip each other up. It's also why you can hardwire an EVSE to a regular (not a GFCI) circuit breaker.

Ground is NOT required for the GFCI function to work properly! Ground IS required for code and safety of the box itself. THere's a big difference...Taking quotes out of context is misleading.

jadnashuanh said:

Ground is NOT required for the GFCI function to work properly!

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As a matter of physics, this is accurate. Ground is only required if one wishes to be compliant with the manufacturer's installation instructions and the NEC, as well as to prevent the frying of one's 'nards. Your post, however stated "..ground is NOT required in the circuit at all!", which could be misleading.

jadnashuanh said:

Ground IS required for code and safety of the box itself.

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True.

jadnashuanh said:

Taking quotes out of context is misleading.

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True.

Apologies if I offend, but a cursory reading of your post might lead DIY installers down an unsafe path. I am certain that we agree on the larger issues at stake.

ultraturtle said:

ted99 said:

Sorry, but a neutral, or ground wire is required for a level 2 ESVE.

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A ground wire is required. A neutral is not. They are not the same thing, and using one in place of the other can be hazardous.

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Inquiring minds want to know; Please explain the difference between ground and neutral and how it's applied in household use. For instance the newer dryer connections have a 4th wire. Is this a "neutral" and what is it's purpose?

ted99 said:

Inquiring minds want to know; Please explain the difference between ground and neutral and how it's applied in household use. For instance the newer dryer connections have a 4th wire. Is this a "neutral" and what is it's purpose?

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The neutral wire is white and the ground wire is green or bare. Both connect back to the same ground bus in the service panel. So the difference is a little esoteric and involves their intended use rather than what they connect to. Technically they are referred to as the "grounded neutral" and the "grounding" wire.

The neutral carries current back to the service panel on a 120V circuit and may carry current in a 240V circuit. Thus due to resistance the grounded neutral wire may go above 0V and be a little hot. I think the neutral is only really needed in a 240 V circuit if you are going to pull power unevenly from the two hots, the imbalance has to flow back through the neutral. Or possibly part of the equipment wants to use 120V between a hot and neutral.

The grounding wire only carries current in an emergency malfunction situation. It is mainly used to make sure metal cases and frames remain at ground. If a hot wire should short to a metal case the grounding connection will ensure the short causes the circuit breaker to trip rather than the case becoming energized and dangerous.

This is an excellent explanation. Thanks for saving me the trouble of writing something that would no doubt be less clear.

KurtEndress said:

ted99 said:

Inquiring minds want to know; Please explain the difference between ground and neutral and how it's applied in household use. For instance the newer dryer connections have a 4th wire. Is this a "neutral" and what is it's purpose?

Click to expand...

The neutral wire is white and the ground wire is green or bare. Both connect back to the same ground bus in the service panel. So the difference is a little esoteric and involves their intended use rather than what they connect to. Technically they are referred to as the "grounded neutral" and the "grounding" wire.

The neutral carries current back to the service panel on a 120V circuit and may carry current in a 240V circuit. Thus due to resistance the grounded neutral wire may go above 0V and be a little hot. I think the neutral is only really needed in a 240 V circuit if you are going to pull power unevenly from the two hots, the imbalance has to flow back through the neutral. Or possibly part of the equipment wants to use 120V between a hot and neutral.

The grounding wire only carries current in an emergency malfunction situation. It is mainly used to make sure metal cases and frames remain at ground. If a hot wire should short to a metal case the grounding connection will ensure the short causes the circuit breaker to trip rather than the case becoming energized and dangerous.

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Since the ground wire does not need (nor should, except in a fault condition) carry current, on some circuits, you are allowed to make the ground wire smaller than the current carrying wires. IOW, the ground is only there as a safety, second path back to the system ground and may be needed to trip the CB or blow the fuse in a fault condition. IN something like your dryer or stove, they used to only have neutral and the two power leads...current code for a long time, requires the addition of a ground (this is all USA and Canada wiring, not places where 240vac is the 'normal' power supplied to the building - in USA parlance, we use split phase). Your stove and dryer used the neutral to achieve 120vac to run things like the timer, maybe an accessory receptacle, and the on-board light bulbs so you didn't have to try to find a 240vac light bulb for say the oven. On an EVSE, it runs everything internally off of the 240vac coming in, and ground is only there for safety. Well, except for the occasional use unit that comes in the NA market which runs off 120vac - but that just plugs into a 'conventional' receptacle. On our power, neutral is the center-tap of the transformer wiring...we really have 240vac coming in, but if you tap into the middle of the transformer, it looks like two 120vac circuits. The car gets power run to the two power leads, and it senses whether it is 120vac or 240vac by itself to make sure the car gets charged properly...almost exactly like your shaver charger that will work on say 100-260vac...it adjusts itself to the power coming in, but in this case, it's a MUCH bigger power supply!