Model S - HPWC (High Power Wall Connector)

[tga]

Okay, maybe mine is gen 2 because it does support 80A. I never had dual chargers so it wasn’t an issue for me. The new one in the box is likely 3rd gen then.

IIRC, both gen 1 and gen 2 can supply 80A (100A circuit), while gen 3 is limited to 48A delivered (60A circuit). Gen 1 were independent (no load sharing), gen 2 added load sharing (communication over RS485). Gen 3 uses wifi for load sharing.

The Tesla Wall Connector says to use a 60 amp. Do as recommended, dont second guess it. I think your 50 amp breaker would be tripped with a 48amp current.

All WC's can be configured to "know" the breaker size and only supply 80% of the circuit rating. You can configure it for a 50A circuit just as easily as a 60A one.

 

[Olle]

I had this setup for my 2013 P85 that had dual chargers. I can count on one hand the times that it was useful. Typically those were race home and charge while loading the car for a road trip.

Meanwhile walking on pins and needles hoping that the house HVAC is not running high and somebody turns on the dryer or oven and boom, the service panel trips .

That's why I never set up 100A back in the day when I had a dual charger P85 . The car saved me a good amount of time though on old Sun Country Highway 70A chargers before there were superchargers.

 

[tga]

Meanwhile walking on pins and needles hoping that the house HVAC is not running high and somebody turns on the dryer or oven and boom, the service panel trips .

You just need Tim Allen to help design your electrical system - "More POWER!!!"

 

[davewill]

Thanks! I beleive what Is there is in (flexible) conduit (looks like bx but larger… I didn’t install it, so I’m not 100% sure what it is. I read the gauge of the conductors from inside the box.

Is that the whole run, or just between a wall box and the wall connector? It's not unusual for the installer to use flex conduit or armored cable as the last step between the wall and the wall connector, while using something else for the run in or on the walls.

 

[Jeffsstuff]

Is that the whole run, or just between a wall box and the wall connector? It's not unusual for the installer to use flex conduit or armored cable as the last step between the wall and the wall connector, while using something else for the run in or on the walls.

Yup. it runs over the garage and right out to the panel. It’s only in the wall to get through to the panel which is outside. Not a very long run at all.

 

[brainhouston]

Snatched myself a used Gen2 from eBay for $320 since i have 72amp charger.
I have 200amp panel in garage with only AC and dryer on 240V so i think im good for load.
Plan to install 14-50 right below (50a breaker, 6/3 romex) and
HPWC 1-2ft to the left of panel.

Question regarding below:

1. HPWC, 100 Amp Circuit Breaker, #3 wire, 80 Amp charging. You will probably spend an hour or two more for the electrician if he uses #2 wire in addition to the cost of the wire. #2 is a real pain to route inside the HPWC.
2. HPWC, 90 Amp Circuit Breaker, #4 wire, 72 Amp Charging.
3. HPWC, 60 Amp Circuit Breaker, #6 wire, 48 Amp Charging. With the right insulation and inspector, you might even be able to push this to 56 Amp Charging on a 70 Amp CB.
4. 14-50, 50 Amp Circuit Breaker, #6 wire, 40 Amp charging.
5. 14-30, 30 Amp Circuit Breaker, #8 wire, 24 Amp Charging.

I wanna go with option 2 but confused on wiring...
Most ppl say use #3 THHN but my local stores don't have it...
Can you really do #4? THHN or 4/3 NH-B?
Do I need a conduit for THHN inside the wall?

Apologies if this was answered, i only skimmed about 60 pages so far...

 

[MP3Mike]

Do I need a conduit for THHN inside the wall?

I can answer this one: yes. You can't just string THHN inside a wall.

As far as gauge I thought #4 was only rated to 70A. But definitely not the Romex/NH-B variety.

 

[ucmndd]

I wanna go with option 2 but confused on wiring...
Most ppl say use #3 THHN but my local stores don't have it...
Can you really do #4? THHN or 4/3 NH-B?

#4 THHN in conduit is rated for 85 amps and you need a 90 amp circuit to charge at the full 72 amps - so no, you really need #3 or larger. 4/2 or 4/3 romex is limited to 70 amps.

 

[davewill]

Yup. it runs over the garage and right out to the panel. It’s only in the wall to get through to the panel which is outside. Not a very long run at all.

Sounds like THHN in flex conduit, then, which should be good for a 60a breaker and 48a charging.

 

[brainhouston]

#4 THHN in conduit is rated for 85 amps and you need a 90 amp circuit to charge at the full 72 amps - so no, you really need #3 or larger. 4/2 or 4/3 romex is limited to 70 amps.

so close haha...
but electrically speaking, running 72amps thru couple of feet #4 THHN wire won't burn the house down, ignoring the codes

 

[davewill]

so close haha...
but electrically speaking, running 72amps thru couple of feet #4 THHN wire won't burn the house down, ignoring the codes

If it's only a few feet, why not either upsize to #2, or source the #3 online?

Heck, someone in this thread has probably got more than a few feet just kicking around their garage...

 

[brainhouston]

If it's only a few feet, why not either upsize to #2, or source the #3 online?

Heck, someone in this thread has probably got more than a few feet just kicking around their garage...

For sure, im looking for #3 online
#2 seems like overkill n hard to work with so trying to stay away from it...
Just speaking from ease of installation, #4 would be great n probably work just fine but won't pass the code...

If anyone got couple of feet laying around i'd be happy to cover shipping if its reasonable.

Love your "Tesla Jr." note

 

[brainhouston]

2. HPWC, 90 Amp Circuit Breaker, #4 wire, 72 Amp Charging.

So, was that statement wrong? or is there other type of #4 wire that can handle the load by code?

another question i forgot to ask, local stores seem to carry this:

2/3 Stranded Romex SIMpull CU NM-B W/G Wire​

will that work for 72amp? since its rated at 95amps...
and will it fit into Gen2 terminals?

 

[tga]

So, was that statement wrong? or is there other type of #4 wire that can handle the load by code?

Sort of wrong. See my post on the prior page:

Expanding on this, 6ga copper has different ratings at different temps (all ratings are intermittent). 60 deg C = 55A, 75 deg C = 65A, 90 deg C = 75A. You can only use the lowest degree C rating for all components in the circuit. For residential, that's either the 75C ratings of your breaker, or the 60C rating of romex. THHN in conduit is good for 90C, but your breaker terminals aren't, so you would be limited to 75C=65A with THHN.

You are allowed to round up the rating for non-standard breaker sizes (so a 60A breaker on #6 romex, 70A breaker on THHN/conduit), but that's only for the breaker, not the circuit rating as a whole - the wire is still the limiting factor.

The problem is, most THHN is rated for 90C, but the terminals it attaches to most be rated for 90C as well. You're bound by the weak link in the chain. I've never seen a residential breaker with 90C terminals. I've theorized in the past that it may be code compliant to splice a few feet of #2 to the either end of a long run of #4, using 90C rated Polaris connectors or the like, but it's sort of silly - you still have the headaches of using #2 in the terminals and higher voltage loss of #4. I guess you saved a little bit on wire costs, but for a short run, why bother?

another question i forgot to ask, local stores seem to carry this:

2/3 Stranded Romex SIMpull CU NM-B W/G Wire​

will that work for 72amp? since its rated at 95amps...
and will it fit into Gen2 terminals?

Yes it will work for 90A circuit/72A charging. It will fit (as will any #2). But you're wasting money - you're paying for a completely worthless (in your application) third #2 neutral wire. All of Southwire/SIMpull 2 and 4 gauge NM-B is 3 wire (+ground).

I supposed you could also use 2 conductor+ground copper SER/SEU - Copper Service Entrance (SEU) Cable | Southwire - but THHN in conduit is probably a lot easier to use.

 

[brainhouston]

Sort of wrong. See my post on the prior page:

The problem is, most THHN is rated for 90C, but the terminals it attaches to most be rated for 90C as well. You're bound by the weak link in the chain. I've never seen a residential breaker with 90C terminals. I've theorized in the past that it may be code compliant to splice a few feet of #2 to the either end of a long run of #4, using 90C rated Polaris connectors or the like, but it's sort of silly - you still have the headaches of using #2 in the terminals and higher voltage loss of #4. I guess you saved a little bit on wire costs, but for a short run, why bother?

Thanks, very informative! Definitely not worth it.

Yes it will work for 90A circuit/72A charging. It will fit (as will any #2). But you're wasting money - you're paying for a completely worthless (in your application) third #2 neutral wire. All of Southwire/SIMpull 2 and 4 gauge NM-B is 3 wire (+ground).

I supposed you could also use 2 conductor+ground copper SER/SEU - Copper Service Entrance (SEU) Cable | Southwire - but THHN in conduit is probably a lot easier to use.

i was just curious, thinking not using conduit might be easier. i have wired the house circuits on few occasions but never with conduit.

of topic question, do wires/terminals actually heat up to their rating (60/75/90) in continuous (80%) draw circuit? how do actual physics work out for these ratings...

 

[brainhouston]

anyone got an unused rear entry bracket for Gen2 that they don't mind letting go?
i bought used one with only top entry n i'd rather not use it, since i'll be doing rear entry.

 

[Fiver]

anyone got an unused rear entry bracket for Gen2 that they don't mind letting go?
i bought used one with only top entry n i'd rather not use it, since i'll be doing rear entry.

View attachment 848358

I probably do. If you still need one shoot me a PM.

 

[Justwn]

Hey all, I’m having some odd symptoms on my gen1 HPWC (from a previous owner). Test mode has the sequential green lights (don’t hear any clicking of connectors contrary to the manual - perhaps a fried or broken part?).

Green light stays solid with DIP switches set to 40A breaker, and attempting to charge results in a one or two yellow flashes on the WC with the green light staying lit the whole time. Car states “Charging Stopped - Power Lost While Charging”.

I have it pig-tailed to a 14-50, which is mated with a 40A breaker. Neutral is capped off and I’ve ground has been tested attached to and off the bolt (as pictured). I’ve included the wiring of the unit below. Any ideas/advice?

 

[davewill]

Hey all, I’m having some odd symptoms on my gen1 HPWC (from a previous owner). Test mode has the sequential green lights (don’t hear any clicking of connectors contrary to the manual - perhaps a fried or broken part?).

Green light stays solid with DIP switches set to 40A breaker, and attempting to charge results in a one or two yellow flashes on the WC with the green light staying lit the whole time. Car states “Charging Stopped - Power Lost While Charging”.

I have it pig-tailed to a 14-50, which is mated with a 40A breaker. Neutral is capped off and I’ve ground has been tested attached to and off the bolt (as pictured). I’ve included the wiring of the unit below. Any ideas/advice?



View attachment 850742

Well, that white wire is not a ground, it's a neutral. It should not be connected at all. Connecting it to ground can cause all sorts of strange symptoms, especially if this circuit is fed off of a subpanel. (Edit: I zoomed in closer and I guess that white wire is wrapped in tape and not connected to that bolt.)

Beyond that, it sounds like the contactors are not tripping, which could be a bad contactor, or a problem on the logic board. Some careful probing with a multimeter could tell you which it was, but unless you have experience, I don't recommend you try.

 

[MN-MS100D]

Justwn-

That pigtail is a hatchet job. You cannot wire a pigtail cord to the HPWC--the lugs are not rated for the fine stranded wire. Also, you do not have any (apparent) strain relief on the incoming cable powering the HPWC. This is a problem waiting to happen late at night.