Model S - HPWC (High Power Wall Connector)

[eprosenx]

+1

My local inspector was not aware of an EV section in the code — I had to point it out to him. When I installed my WC with a 100-amp breaker he said it either had to be lockable or accessible and line-of-sight.

Hah, while this makes logical sense to me (either lockable OR line-of-sight) this is absolutely not how the code actually reads. It is funny how different jurisdictions just make up their own rules (sometimes more strict, sometimes less strict).

Here are the code sections:

So if you are OVER 60 amps on a circuit into your Wall Connector then a disconnecting means must be installed in a readily accessible location. You must be able to lock it in the off position. By my reading- A metal clip on the breaker that lets you lock the breaker "off" meets these needs (even if the breaker panel is elsewhere in the house - Readily Accessible to me just means you don't have to use ladders, etc...)

The other part of 625.43 applies if you are *more* than 150 volts to ground, but 240/120v split phase residential service will NEVER fall into this condition. This would apply if you had 277v going into a HPWC (which Tesla used to support, but they have taken it out of the manual).

In my case, I have a 60a breaker for my Wall Connector that I use to charge my M3. I triggered neither of these conditions, so I did not need a breaker lock-off device.

I have heard of jurisdictions requiring a disconnect switch right at the HPWC (like an AC unit requires), but this is NOT how I read the definition of "Readily Accessible" in Article 100. It seems silly to me. You don't generally have technicians accessing HPWC's all the time for maintenance like you do air conditioner units.

 

[ohm-ms]

Waiting for MS to arrive, thought I’d share my wall connector install. I still need to figure out the best way to wrap the 24’ cord. Anyone have a recommendation?

 

[miimura]

Waiting for MS to arrive, thought I’d share my wall connector install. I still need to figure out the best way to wrap the 24’ cord. Anyone have a recommendation?

My suggestion is to untwist the cable so it loops flatter. Then coil it over the unit going counter-clockwise so the cable has a large loop under the unit before entering the holster. It currently has a sharp bend to double back on the same side of the unit.

 

[SoCalNick]

My electrician is installing the HPWC right now.
DANG that 2AWG cable is heavy duty. I dread to think what the wiring is like inside of an actual SuperCharger.

FYI, I'm installing two circuits; a 100A circuit with 2AWG for the HPWC and a 50A circuit with 6/3 AWG for the 14-50 connector.
The HPWC will be my go-to charging, but the 14-50 is in case I need an alternative.

 

[eprosenx]

My electrician is installing the HPWC right now.
DANG that 2AWG cable is heavy duty. I dread to think what the wiring is like inside of an actual SuperCharger.

FYI, I'm installing two circuits; a 100A circuit with 2AWG for the HPWC and a 50A circuit with 6/3 AWG for the 14-50 connector.
The HPWC will be my go-to charging, but the 14-50 is in case I need an alternative.

Is the cable in conduit for the 2awg? If so, you could have gotten away with 3awg which is slightly smaller. Even 2 awg I don’t think I is big enough for 100a if it is just romex (non conduit).

 

[SoCalNick]

Is the cable in conduit for the 2awg? If so, you could have gotten away with 3awg which is slightly smaller. Even 2 awg I don’t think I is big enough for 100a if it is just romex (non conduit).

Definitely in conduit. The 2AWG is what he had lying around, and this project is under "friend and family" so I'll take what he has.

I had to buy the 6/3 for the 14-50 outlet, and it was $3 per foot. Ouch.

 

[eprosenx]

Definitely in conduit. The 2AWG is what he had lying around, and this project is under "friend and family" so I'll take what he has.

I had to buy the 6/3 for the 14-50 outlet, and it was $3 per foot. Ouch.

Yeah, copper ain’t cheap right now!!!

2 AWG innconduit on a 100a will be KILLER! It is super future proofed and will run nice and cool. Having a backup 14-50 is awesome as well!

Post pictures when you are done please!

 

[AWDtsla]

2 AWG innconduit on a 100a will be KILLER! It is super future proofed and will run nice and cool.

Tesla hasn't gone over 72A in years. Hard to say that they ever will again. They have turned back the amperage on everything, sometimes sneakily. If I were doing it now I wouldn't bother with the expense and frustration. 2AWG is hard to work with.

 

[eprosenx]

Tesla hasn't gone over 72A in years. Hard to say that they ever will again. They have turned back the amperage on everything, sometimes sneakily. If I were doing it now I wouldn't bother with the expense and frustration. 2AWG is hard to work with.

The original model S was a 40a charger which needed a 50a circuit. If you got the double charger it was 80a on a 100a circuit.

The new S and all X's are 72 amp chargers which require 90a circuits.

Model 3 Long Range (all they are selling right now) units are 48 chargers which require 60a circuits.

So yes, there is no current production Tesla that can make use of a 100a circuit, but there are lots of them that can make use of a 90a circuit. I think you are not understanding that the 72a chargers require a 90a circuit which is just shy of the full 100a. I don't see how this is sneaky at all. They went from the base Model S having 40a of charging to it having 48a, and then they made the "fast" charging option only 72a vs 80, but if I am not mistaken, I think it is a software locked feature? So not a separate piece of hardware? (someone correct me please if I am wrong) I don't see how this is sneaky in any way...

I personally would probably just do the 100a and be future proofed. Also, you can hook multiple Wall Connectors to the same circuit and have them share the capacity...

 

[AWDtsla]

Model 3 Long Range (all they are selling right now) units are 48 chargers which require 60a circuits.

Yeah, disappointing. Another reason to not trade in my car for a 3.

They went from the base Model S having 40a of charging to it having 48a, and then they made the "fast" charging option only 72a vs 80, but if I am not mistaken, I think it is a software locked feature? So not a separate piece of hardware? (someone correct me please if I am wrong)

Some cars got the 48A hardware. Some cars got the 72A hardware, software locked to 48A. Probably just managing inventory after overproducing one.

I don't see how this is sneaky in any way...

Sneaky part is where UMC2 went from 40 to 32. Then in addition, another amp came off the top. Why? Who knows. It's actually been 11/15/39 vs the claimed 12/16/40/etc after some software update a while ago. Never tried a UMC2, but I bet it's 31 instead of 32. Try putting a ammeter on your socket. Does it matter? A whole lot at 12 amps, for sure.

It's been 3 years since the 72A charger came out. There was no upgrade in charging hardware to let the base charger go over 48A, hence the Model 3 gets 48A.

 

[Rocky_H]

So yes, there is no current production Tesla that can make use of a 100a circuit, but there are lots of them that can make use of a 90a circuit. I think you are not understanding that the 72a chargers require a 90a circuit which is just shy of the full 100a. I don't see how this is sneaky at all. They went from the base Model S having 40a of charging to it having 48a, and then they made the "fast" charging option only 72a vs 80, but if I am not mistaken, I think it is a software locked feature? So not a separate piece of hardware? (someone correct me please if I am wrong) I don't see how this is sneaky in any way...

I wouldn't call it "sneaky" either, but it has been a very definite obvious trend of bringing the maximum charging rate down lower and lower. The Model S originally had the option to do 80A. Then, with the Model X and facelift in 2016, it was brought down to 72A. Now with the Model 3, it is down even further to 48A. I don't know about you, but 80 -> 72 -> 48 looks like a downward trend to most people.

It does seem pretty clear that they are moving toward lower power onboard chargers and just having a more robust Supercharger network to cover faster charging as needed. So a lot of this "future proofing" is probably going to be useless as far as a single car goes. Obviously it is good and relevant, though, as far as adding 2nd and 3rd EVs to a household, though.

 

[SoCalNick]

I just wanna say - anyone who complains about paying $$$ to the electrician for installing a HPWC is being a cheap ass.

It took us 8 hours (including dinner break) to install the HPWC yesterday. Those cables are a bitch to work with. the bend necessary to connect into the HPWC is tough with cables that thick. And pushing & pulling those cables back and forth in the conduit was a pain also.

BUT the HPWC is in, and we will do the 14-50 another day. I'm tired, but the car fully charged last night.

 

[rhumbliner]

I just wanna say - anyone who complains about paying $$$ to the electrician for installing a HPWC is being a cheap ass.

It took us 8 hours (including dinner break) to install the HPWC yesterday. Those cables are a bitch to work with. the bend necessary to connect into the HPWC is tough with cables that thick. And pushing & pulling those cables back and forth in the conduit was a pain also.

+1

As a DIY’r, I’ve installed 2 WC’s and 3 14-50 receptacles by myself (for myself and friends). I’ve wrestled with heavy cable, hung conduit, and pulled cable thru conduit in freezing weather and I completely agree. Especially the part about me being a cheap ass.

 

[eprosenx]

I wouldn't call it "sneaky" either, but it has been a very definite obvious trend of bringing the maximum charging rate down lower and lower. The Model S originally had the option to do 80A. Then, with the Model X and facelift in 2016, it was brought down to 72A. Now with the Model 3, it is down even further to 48A. I don't know about you, but 80 -> 72 -> 48 looks like a downward trend to most people.

It does seem pretty clear that they are moving toward lower power onboard chargers and just having a more robust Supercharger network to cover faster charging as needed. So a lot of this "future proofing" is probably going to be useless as far as a single car goes. Obviously it is good and relevant, though, as far as adding 2nd and 3rd EVs to a household, though.

A number of things I want to respond to here and from the last post but I don’t have time at the moment.

I wanted to call out that since the Model 3 is much more efficient than the Model S or X it does not need as large a charger to have the same effective charging speed (miles per hour of charge, not kW).

My Model 3 charged at 48a and I think it is the “right” size charger for the car. My commute is only a little over 30 miles a day and the car is able to regenerate that charge in about an hour (sometimes a little more if I ran errands on the way home) when I get home.

Dead empty to completely full should be about seven hours of charging (have not tried that yet).

I think it is well balanced.

I had a Model S loaner for a few days and I was underwhelmed by the 40a Charger on it since the car is more “hungry” and it was a little slower than my M3 amps wise. It still was totally fine though for my driving patterns.

 

[AWDtsla]

A number of things I want to respond to here and from the last post but I don’t have time at the moment.

I wanted to call out that since the Model 3 is much more efficient than the Model S or X it does not need as large a charger to have the same effective charging speed (miles per hour of charge, not kW).

My Model 3 charged at 48a and I think it is the “right” size charger for the car. My commute is only a little over 30 miles a day and the car is able to regenerate that charge in about an hour (sometimes a little more if I ran errands on the way home) when I get home.

Dead empty to completely full should be about seven hours of charging (have not tried that yet).

I think it is well balanced.

I had a Model S loaner for a few days and I was underwhelmed by the 40a Charger on it since the car is more “hungry” and it was a little slower than my M3 amps wise. It still was totally fine though for my driving patterns.

"enough" is a different argument than "awesome". I charge at ~56 mph. That's SP90D miles. You Model 3 guys aren't beating that even if more efficient miles.

Most people could get by with 110 charging. It's "enough"

 

[Edison]

I posted this in "Energy" by mistake, I think it belongs here.
This morning I saved $550. Our Gen 1 HPWC and 2015 P85D stopped charging with a red light at the port and error code
"No wall power/Charge interrupted: check power source." A friend works for Tesla (his name is not Elon), he came by with a 2018 model S and a laptop. After a few false starts we got an error code indicating a bad ground connection in the cable. I had cleaned the connections and tested the continuity with a meter, but the ground connector on the cable did look oxidised so a tiny brush and DeOxit contact cleaner were applied with great vigour. Success! I do not need to spend $550 (w/tax) for a new wall charger!
So I guess the point is to be sure the connector contacts and vehicle contacts are shiny clean before you give up on your wall charger.

 

[SoCalNick]

Just posting a quick photo.

 

[eprosenx]

Just posting a quick photo.

Beautiful install! Nice job!

 

[Arcam]

Do you guys in the US have a choice between 110v and 220v?

Obviouly 110v cables have to be twice at thick to carry the same power which makes them a pain to route, in the UK we have 230v (nominal) so for 7.2Kw we just need 32a which runs on 6mm cable just fine.

 

[Rocky_H]

Do you guys in the US have a choice between 110v and 220v?

No, it's 120V or 240V. That's for residential. In commercial buildings they have 120V and 208V because it's coming more directly from a 3 phase system.

Obviously 110v cables have to be twice at thick to carry the same power which makes them a pain to route,

Well sure, if you're expecting to carry the same power, but that's not how it's done. Any regular small circuits within the house for lights and refrigerators and TVs and such just don't need to be high power, so they use the 120V circuits, which is considered to be a bit safer because of lower shock risk than the higher voltage. For any circuit that does need to be high power, like an air conditioner or electric clothes dryer or car charging, we do use a 240V circuit for that.