They still have HPWCs, though they call them WCs now:
- Gen 2: Gloss Black Wall Connector - Gen 2
- Gen 3: Wall Connector
Edit: Or did you buy a WC that came with the 14-50 pigtail already attached? (Which they no longer offer.)
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charging voltage dropping from 40a to 30a
- Thread starter r1200gs4ok
- Start date
They still have HPWCs, though they call them WCs now:
Edit: Or did you buy a WC that came with the 14-50 pigtail already attached? (Which they no longer offer.)
How long is the run? What breaker are you using on the main panel? Check the heat at the panel and on the breaker. The draw is likely strained somewhere from point to point and the car can sense it and adjusts the draw. For the many things Tesla has done wrong, the car's voltage protection systems for charging are seemingly bulletproof.
murphyS90D
Member
I was not aware that such an EVSE existed.
In that case my question is where did the 14-50 outlet come from? Did it come from Lowe's or Home Depot or is it a high quality industrial version? The recommendation to use copper ferrules still applies. 6 AWG is stranded wire and all of the strands must be securely clamped or the connection will get hot. A copper ferrule guarantees that all of the strands are crimped together into a solid block of copper.
This assumes that whoever crimped the wire did it properly.
Hi rt1200gs4ok,
You have a unicorn - that charger with the 14-50 plug was only for sale briefly...
Your lower voltage may also contribute to your problem...
You have options...
(My opinion) The best option would be to remove the pigtail from the HPWC
and have the electrician wire directly into the charger.
With the proper wire and terminations you should easily be able to get 40 Amps from the HPWC.
This could come from the same 50 Amp breaker now feeding the 14-50 connection...
and remove the 14-50 outlet.
If you have the money and the need for 2 charging outlets:
Leave the 14-50 outlet alone and use it with the Universal Mobile Connector.
The UMC Gen2 which I got with my 2018 X is capable of charging at 32 Amps.
Be sure if you leave the 14-50 in place that it is a good quality outlet.
Maybe someone can add and classify the good and bad brand names...
UMC Gen 1 is usually available on eBay and will charge at 40 Amps.
If you chose the leave the 14-50 outlet (with a quality receptacle) in place,
You will still need the electrician to remove the pigtail from the HPWC
and install a new breaker and good copper wire for a hard wired install.
Please read the suggestions mine and others carefully.
We wish you to enjoy your cars, life, and home without any electrical fires...
Good luck,
Shawn
You have a unicorn - that charger with the 14-50 plug was only for sale briefly...
Your lower voltage may also contribute to your problem...
You have options...
(My opinion) The best option would be to remove the pigtail from the HPWC
and have the electrician wire directly into the charger.
With the proper wire and terminations you should easily be able to get 40 Amps from the HPWC.
This could come from the same 50 Amp breaker now feeding the 14-50 connection...
and remove the 14-50 outlet.
If you have the money and the need for 2 charging outlets:
Leave the 14-50 outlet alone and use it with the Universal Mobile Connector.
The UMC Gen2 which I got with my 2018 X is capable of charging at 32 Amps.
Be sure if you leave the 14-50 in place that it is a good quality outlet.
Maybe someone can add and classify the good and bad brand names...
UMC Gen 1 is usually available on eBay and will charge at 40 Amps.
If you chose the leave the 14-50 outlet (with a quality receptacle) in place,
You will still need the electrician to remove the pigtail from the HPWC
and install a new breaker and good copper wire for a hard wired install.
Please read the suggestions mine and others carefully.
We wish you to enjoy your cars, life, and home without any electrical fires...
Good luck,
Shawn
IndyToronto
Member
I'm curious if anyone with a NEMA 14/50 connector at home is able to get more than 32amps (8kW) charging with the gen 1 mobile charger cable. I understand the gen2 nema 14/50 is capped at 32amps but some people have reported they were charging with 40amps. Yes I have the gen1 cable and the cable is thicker than the gen2 I see on other teslas. They are no longer sold in tesla store. It' all gen2 now.
Perhaps it's just the 2016 and earlier models that is capped at 32amps?
My installation is correctly done, 6 gauge copper, about 20feet cable to box. Car can charge at high enough rate at supercharger, but car still caps the charging to 32amps even when I set the cap to 40amps. This is not a serious issue yet as there is more than enough time to charge overnight, just want to know that it is a deliberate setting by tesla safety policy and not something wrong with my NEMA 14/50 wall plug (which I'm certain is ok and is always cool).
Perhaps it's just the 2016 and earlier models that is capped at 32amps?
My installation is correctly done, 6 gauge copper, about 20feet cable to box. Car can charge at high enough rate at supercharger, but car still caps the charging to 32amps even when I set the cap to 40amps. This is not a serious issue yet as there is more than enough time to charge overnight, just want to know that it is a deliberate setting by tesla safety policy and not something wrong with my NEMA 14/50 wall plug (which I'm certain is ok and is always cool).
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IndyToronto
Member
I do have the rare gen1 mobile charging cable but it still caps charging to 32amps with the NEMA 14/50. According to teslafi, my voltage is between 242V to 246 in 2020 and there's every little fluctuation when charging at night. The cable still doesn't allow me to charge at more than 32amps. I wonder if it is deliberately capped by tesla for safety reasons. But then again, my model year is 2016.
my run is less than 5 feet, using 6awg......panel is just on the other side of the wall.....the breaker came from the professional electrician......there is no heat at breaker panel.....when charging the pig tail leading from the wall outlet to the charger is Luke warm and the charger handle wire is Luke warm......I just measured the voltage at the Nema 14-50 and it was 239vac......its 120vac at each line
The Gen 1 Canadian 14-50 adapter limits you to 32 amps. If you get a Gen 1 US 14-50 adapter you could do 40 amps. Originally they were the same, but at some point they recalled the Canadian adapters and replaced them due to different regulations in Canada. (Or at least that is what I recall.)
Hi IndyToronto,
I bought a UMC Gen1 for my 2018 Model X.
In USA it charges fine at 40 Amps...
Shawn
I bought a UMC Gen1 for my 2018 Model X.
In USA it charges fine at 40 Amps...
Shawn
My breaker came from a professional and it burnt itself up, the car let me know there was a problem before my house burned down basically. I would, just for sanity's sake, remove the breaker and check it for burns or scoring. Obviously do all the other safe steps first...
hi Shawn......I thank you for all the assistance and that from others......I have the electrician who did the install coming this afternoon.....I have checked the voltage at the expensive Nema 14-50 and am getting 239vac, and 120vac on each line......breaker in panel is brand new.....
I think my best choice is to hard wire the charger directly from the panel if I can do that......my panel is at it max so I cannot install another breaker or I would leave Nema alone, disconnect pigtail and hard wire to charger......if that fails the test, I guess Tesla will want to see original set up and determine it is the charger is bad and see if they will replace under warranty.....its less than a year old....
will keep you guys advised
IndyToronto
Member
will do this afternoon when electrician comes to check the install.....I believe it is a bad breaker or loose connection at the pigtail......
Huachipato
Member
Yes - the Gen 1 Mobile charger that came with my car - used it for about 9 months and it could do 40AMPs all day long on my Nema 14-50 plug. I removed the plug and rewired to install a HPWC on a 100 Amp breaker - set it to 80Amps but car will only gets 40Amps out of it.
Decibelle
Member
MP3Mike is correct. Here in Canada they started out supplying the 40A (NEMA 14-50) adapter with new cars, but later changed them to adapters that maxed out at 32A. I heard rumors the service centers were exchanging the adapters that were in the trunk without asking the customers so I removed mine just in case. Still using the 40A every day. Just make sure the wire is 6awg or thicker and not 8awg if you are going to use the one that allows you to charge at 40A.
murphyS90D
Member
If the car only has one charger installed you will not get more than 40 amps no matter what the HPWC is set to.
well the electrician came by and I went through all the the things that I did......then I showed him the data from teslafi.....we proceeded to take our the 14-50 receptacle and re-tightened all terminals......then we looked at the panel breaker....it looks good....no heat build-up and just a little discoloration but that was expected.....we changed the breaker......by changing the breaker, it automatically re-sets the HPWC unit.....
we then applied power and watched as the charger booted up......
plugged into my MS and for 45 min watched....
charger booted up to 40a and 233v.....it stayed that way......
we measured the heat at the panel breaker, NEMA 14-50, pig tail wire to the charger, and the wire from the charger to the handle.....all were between 78F - 95F
during the 45 minute period, it did stay at 40a and 233v.......currently I am at SoC 49% and will charge to 90% tonight...
if the amperage and voltage stays consistently the same throughout the charge, I think we can say that it may have been the breaker or the re-setting of the charger fixed this issue.....
last night I reset charger by pushing the reset button.....charged my wifes car (which had the same issues) and charger stayed at 40a and 233v for the entries charge of 1.5 hrs but did drop to 30a and 226v for the last 10 minuets....I wonder if that is due to the slowing down prior to completing the charge.
will report later on how my charge goes after 2100 from 49% to 90%
The voltage won't drop during the taper at the end of the charging. (If anything it should go up as the amperage goes down.) If the voltage dropped to 226v mid-charge even after the car reduced to 30a then either you had a wiring problem or an electrical service problem. I would bet on the issue being a bad/loose connection before I would bet on it being a bad breaker.
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