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Plug HPWC into a NEMA 14-50 plug?

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Hi -
I'm considering the high power home charging option, largely because of the dual charger. I don't need HPWC charging speeds at home. Instead, I'm thinking of installing a NEMA14-50 outlet. Conveniently, the location will be directly next to our main breaker. Also, the NEMA 14-50 outlet will be useful in charging our Leaf.

My question is - can I wire the HPWC to plug into the 14-50 outlet via a male plug (setting the dip switches to 50A)? Meaning, rather than have it hard-wired. Additional benefit here is that it's easy to move in the event we relocate.

Thanks!
tomp
 
People sell their HPWC all the time in the Tesla Parts for Sale section.

Out of curiosity, why did you get dual chargers if you are fine with the 40A charging you'll get from a 14-50 outlet?

To clarify, I haven't ordered the car yet. The thought is to get the dual chargers to be able to take advantage of HPWC at Tesla store/service locations, private locations, or potential (rare) high amp J1772 chargers - primarily in the event of road trips to give some additional flexibility.

Thanks.
 
Hi -
I'm considering the high power home charging option, largely because of the dual charger. I don't need HPWC charging speeds at home. Instead, I'm thinking of installing a NEMA14-50 outlet. Conveniently, the location will be directly next to our main breaker. Also, the NEMA 14-50 outlet will be useful in charging our Leaf.

My question is - can I wire the HPWC to plug into the 14-50 outlet via a male plug (setting the dip switches to 50A)? Meaning, rather than have it hard-wired. Additional benefit here is that it's easy to move in the event we relocate.

Thanks!
tomp

You can sell the HPWC and buy a second UMC for the home charger with 14-50 adapter for $525 + tax, leave the original UMC with all adapters in the car for the road. That's what I did (after buying and returning the HPWC.) About $700 price difference.

I don't believe that plugging a HPWC into a 14-50 outlet is up to code and likely won't pass inspection, and for the hardwired installation you'll need a disconnect switch between the breaker and the HPWC. Setting the HPWC to a 50A breaker will give you 40A charging, same as the UMC.
 
My question is - can I wire the HPWC to plug into the 14-50 outlet via a male plug (setting the dip switches to 50A)? Meaning, rather than have it hard-wired. Additional benefit here is that it's easy to move in the event we relocate.

It's a gray area, but bottom line is that you should be okay with it.

If you call the HPWC electrical infrastructure, it is subject to code and would likely be considered violating code by an AHJ because NEC 625.13 requires that it be tested & listed as "suitable for the purpose" to be connected with cord-and-plug (otherwise all EVSE must be hard-wired and fixed). The HPWC is indeed listed, but it was listed as a direct-wire unit; adding a cord-and-plug set invalidates the listing. Your AHJ (authority having jurisdiction, the official inspection authority) might find it acceptable in any regard; (s)he has final say as to whether something is acceptable under NEC and local codes.

On the other hand, you could argue that the HPWC is an electrical appliance and the NEC doesn't apply; in that case it would no longer be listed, but would be a safe application provided that the DIP switches were set for a 50A circuit, a proper #6 cord and NEMA 14-50 plugs and receptacles are used.

My recommendation, however, would be to provision the garage with a small subpanel for EV charging, and then have a short run to the HPWC. That way, the removal of the equipment if you move is relatively simple and the home is left with provisions to charge other EV's should the new owners have one.
 
I understand your primary point is regarding the potential to plug the HPWC in to a recpticle rather than hard wire, but since the suggestion of just using your UMC came up, in another thread the issue of HPWC vs. UMC came up for "daily charging", and I mumbled something like the following:

scaesare said:
I got the HPWC as well, but more than just for aesthetics (although I must admit it looks cool):

- I plan on an 100A installation at some point... while the 50A circuit I currently have is plenty for overnight charging... there are cases where a "fast turnaround" or decision for spontaneous trip have come up, and the near-60MPH charge rate would be preferable over the under-30MPH rate

- I don't consider the UMC "permanent installation" device. As a matter of fact the "M" in "UMC" stands for "mobile". I understand leaving it plugged in most of the the time, but I'm not sure that time, flex, weight, etc... won't take it's toll on the plug-head/adapter combo.

-The HPWC has a cable hanger and "plug hook" in addition to the above-mentioned slightly longer cable.

- I want a charging cable in the car at all times. That means that if I want a permanent UMC for the garage, I'm already at $650. Spending the difference for the HPWC for the above reasons isn't that much of an additional expense in the overall scheme.
 
The thought is to get the dual chargers to be able to take advantage of HPWC at Tesla store/service locations, private locations, or potential (rare) high amp J1772 chargers - primarily in the event of road trips to give some additional flexibility.
Given the underlined, another option to consider (as pointed out in another thread) is to go ahead and get the HPWC, install it at "full powa!" and consider becoming one of those "private locations" for the benefit of other drivers.
 
Thanks to all for the helpful replies.
Given the underlined, another option to consider (as pointed out in another thread) is to go ahead and get the HPWC, install it at "full powa!" and consider becoming one of those "private locations" for the benefit of other drivers.
Good point - I have considered this. Downside is then I can't use the NEMA 14-50plug to charge our Leaf.
 
It can be done and I am doing this successfully for over two years now. The plug has a 50 amp rating but you said you would limit your HPWC. Just don't unplug when charging which should be easy to do. Arcing can occur when unplugging under load.
 
It can be done and I am doing this successfully for over two years now. The plug has a 50 amp rating but you said you would limit your HPWC. Just don't unplug when charging which should be easy to do. Arcing can occur when unplugging under load.
Thanks - great to know. Was there anything special to know/do when wiring the HPWC to a 14-50 plug? I presume you used an electrician?
 
Isn't it going to be a bit of a pain charging two vehicles from one plug? If your panel can support another 50A breaker, I would at the very least add an additional 14-50 so that you can charge both cars at the same time. Usually, electric companies offer time of use rates to EV owners giving you electric price breaks for charging at midnight. To take advantage of this, you'd have to have two plugs, one for each EV.

Even if you did hard wire the HPWC, moving it won't be that hard. Flip the breaker off, then open up the HPWC, unbolt the three wires going into it from the conduit and then you can take the HPWC away. As a final step, you would open up the breaker panel and unscrew the wires going into the HPWC breaker and cap them off with wire nuts. Then label the HPWC breaker as unconnected.

As others have mentioned, you can sell your HPWC and buy another UMC instead - you can buy Tesla's cord hanger (http://shop.teslamotors.com/products/replacement-high-power-wall-connector-cable-organizer) which works great with the UMC and gives you the same functionality as the HPWC as far as cable organization.

Personally, I would keep the HPWC and hardwire it to the highest breaker size my panel could support. You never know when you'll have done a ton of driving one day and need a bit extra for going out at night. Good call on getting the dual chargers, they do come in handy from time to time.
 
Thanks - in our case having only one plug is OK since we can both generally charge at work. Plus, currently, my wife charges her Leaf via work and supplements when needed via a 120V plug at home.

Good input on ease of disconnecting the HPWC. I didn't realize it was that straightforward.

Thanks!

Isn't it going to be a bit of a pain charging two vehicles from one plug? If your panel can support another 50A breaker, I would at the very least add an additional 14-50 so that you can charge both cars at the same time. Usually, electric companies offer time of use rates to EV owners giving you electric price breaks for charging at midnight. To take advantage of this, you'd have to have two plugs, one for each EV.

Even if you did hard wire the HPWC, moving it won't be that hard. Flip the breaker off, then open up the HPWC, unbolt the three wires going into it from the conduit and then you can take the HPWC away. As a final step, you would open up the breaker panel and unscrew the wires going into the HPWC breaker and cap them off with wire nuts. Then label the HPWC breaker as unconnected.

As others have mentioned, you can sell your HPWC and buy another UMC instead - you can buy Tesla's cord hanger (http://shop.teslamotors.com/products/replacement-high-power-wall-connector-cable-organizer) which works great with the UMC and gives you the same functionality as the HPWC as far as cable organization.

Personally, I would keep the HPWC and hardwire it to the highest breaker size my panel could support. You never know when you'll have done a ton of driving one day and need a bit extra for going out at night. Good call on getting the dual chargers, they do come in handy from time to time.
 
... Downside is then I can't use the NEMA 14-50plug to charge our Leaf.
If you want to charge your LEAF from the same circuit, wouldn't it make more sense to skip the HPWC and put in a 40a J1772 unit? Then you don't have to have the 14-50 (unless you want to), and you don't have to keep plugging and unplugging two EVSEs. You could put in up to a 70a unit and STILL charge the LEAF from it.

Standards exist for a reason.
 
So some further digging revealed that our Leaf actually can't charge via a Nema 14-50. I'm not sure if htat's because we only have the lower level charger or what. But, I decided to skip the NEMA 14-50 and just install the HPWC as intended - hardwired with a 100A breaker.
Thanks,
Tom
If you want to charge your LEAF from the same circuit, wouldn't it make more sense to skip the HPWC and put in a 40a J1772 unit? Then you don't have to have the 14-50 (unless you want to), and you don't have to keep plugging and unplugging two EVSEs. You could put in up to a 70a unit and STILL charge the LEAF from it.

Standards exist for a reason.
 
So some further digging revealed that our Leaf actually can't charge via a Nema 14-50. I'm not sure if htat's because we only have the lower level charger or what. But, I decided to skip the NEMA 14-50 and just install the HPWC as intended - hardwired with a 100A breaker.

You have to have the aftermarket fix for the charge cable, otherwise it's just 120V.