Just had a Tesla charger installed. Charges are going at 12 amp at 246 volt?

[linkster]

The Gen II MC plugged into a 14-50 using 8ga NM-B with a 2-pole 40 should be to code in most areas and is not dangerous in any way.

Gosh, i thought a HPWC and WC are required to be hardwired instead of a kludged oven pigtail jury rig. I wonder what folks do with the extraneous neutral conductor inside a HPWC or WC.

 

[powaking]

As soon as my electrician finished screwing in the last screw for the cover he said 'doh, the dial' so went back and correctly set the dial. Very easy to overlook this step but I can understand why they would set it real low from factory.

 

[APotatoGod]

So very few electromagicians install the entire circuit correctly as they often miss the 125% continuous rule, don’t pull the proper wire/cable gauge, jam an incorrect (some are interchangeable) manufactures 2-pole breaker onto the buss bar because that is all that is in the storage bin inside their truck, and almost never RTFM to properly set the rotory/dip switches.

Good-luck.

Yeah, I still don't have my HPWC installed, as the electrician we initially hired to do it (based on the recommendation of someone working on repairing a separate aspect of our house) tried to pry the back off of the thing, not realizing the removable back plate was already off, and not listening to my insistence to read the manual (which clearly showed that the removable plate was already removed), or to a phone call to our service center where they said not to pry off the back as he was doing. We ultimately had to insist he leave, not installing the HPWC, but not before he also messed up the other circuit he was installing in our house (didn't use the smart dimmer switch we bought for some new lights because he said he couldn't figure it out, so he just installed a normal light switch).

 

[davewill]

The Gen II MC plugged into a 14-50 using 8ga NM-B with a 2-pole 40 should be to code in most areas and is not dangerous in any way.

Sure, but the electrician was paid to install a 50a circuit, used a 50a breaker with 8awg wire, and let the owner proceed to try to charge at 40a. Bad, bad juju. If it was just some existing circuit, I could totally see changing the breaker out for a 40a, and using an EVSE that did 32a charging, but he just paid to have it put in, it should be done right.

 

[ZOMGVTEK]

I don't think the average electrician takes into account the fact that the load in this case WILL draw full power, and for a long duration. With most common circuits, they have a bit more overhead, and or are loaded for a short duration so its a much lower risk. In my experience, commercial electricians are much better with these kinds of things and would be less likely to run a 14-50 on a 40A circuit to save what is likely under $10 in most installs.

Although i'd have to guess many thousands of people are charging on 14-50's that are really 40A circuits. It's probably OK, but I surely wouldn't recommend it. For most installs, even putting in #4 isn't really very expensive unless the run is far. And if you have a long run, you probably should just go for #4 or larger anyways.

 

[Snerruc]

The book that cams with my wall connector referenced non hardwired installs. You just cap ithe neutral off and tuck it in the box.

 

[mswlogo]

Yeah, I still don't have my HPWC installed, as the electrician we initially hired to do it (based on the recommendation of someone working on repairing a separate aspect of our house) tried to pry the back off of the thing, not realizing the removable back plate was already off, and not listening to my insistence to read the manual (which clearly showed that the removable plate was already removed), or to a phone call to our service center where they said not to pry off the back as he was doing. We ultimately had to insist he leave, not installing the HPWC, but not before he also messed up the other circuit he was installing in our house (didn't use the smart dimmer switch we bought for some new lights because he said he couldn't figure it out, so he just installed a normal light switch).

That must have been so awkward. WC is a little oddly put together and you may get in trouble if you don't look through the manual.

 

[mswlogo]

Sure, but the electrician was paid to install a 50a circuit, used a 50a breaker with 8awg wire, and let the owner proceed to try to charge at 40a. Bad, bad juju. If it was just some existing circuit, I could totally see changing the breaker out for a 40a, and using an EVSE that did 32a charging, but he just paid to have it put in, it should be done right.

@linkster is correct.

If someone requested a 14-50 outlet for a UMC Then 8 AWG with a 40A Breaker is legit. It was never a risk to his home, unless they put a 50A breaker which I highly doubt. I think he (the poster) assumed a 14-50 outlet is 50A and that he was gonna be pulling 40A. He can't pull more than 32A, so they set it up for 40A. And the poster was wrong about a 40A continuous load (which makes it clear he doesn't fully understand), because you can't do that with the UMC Gen II. The confusion is that 14-50 is legal for 40A or 50A and it makes little sense to wire and fuse it for 50A when it can only pull 32A. Some folks might look ahead and wire and fuse it for 50A thinking they might upgrade to a wall connector later or have another purpose for the 14-50. Even if they did put 6 AWG, it's better to fuse it to only what you need (40A).

 

[cbaaz]

........... My second house fire........

Yikes !

 

[davewill]

@linkster is correct.

If someone requested a 14-50 outlet for a UMC Then 8 AWG with a 40A Breaker is legit. It was never a risk to his home, unless they put a 50A breaker which I highly doubt. I think he (the poster) assumed a 14-50 outlet is 50A and that he was gonna be pulling 40A. He can't pull more than 32A, so they set it up for 40A. And the poster was wrong about a 40A continuous load (which makes it clear he doesn't fully understand), because you can't do that with the UMC Gen II. The confusion is that 14-50 is legal for 40A or 50A and it makes little sense to wire and fuse it for 50A when it can only pull 32A. Some folks might look ahead and wire and fuse it for 50A thinking they might upgrade to a wall connector later or have another purpose for the 14-50. Even if they did put 6 AWG, it's better to fuse it to only what you need (40A).

Oops, I think I got my threads crossed. I was thinking of a different thread.

 

[NickFie]

The "dial" is in "80%" units. So just to not confuse the OP, you don't set the dial to the Breaker Size. You set it to 80% of the Breaker size (most of the time). Some breakers can be "rounded up" by 5 Amps. So the dial is set to 80% of the Minimum of the Breaker Size or Wire Capacity.

I disagree. Set the HPWC dial to the circuit breaker/ampacity rating. The HPWC will limit charging to 80% of the rating. 40 Amp breaker with proper wire gauge? Set dial to 6. HPWC will only allow 32 Amps.

I had our electrician install 100 Amp breaker in the panel - he verified it was within panel limits. Then had crew run 2-gauge copper to a new sub-panel near the driveway. 100 Amp breaker in the subpanel, 2-gauge copper to the HPWC. That gives us options if we want to install additional HPWC or other charging arrangement. Subpanel with breaker counts as cutoff since it is visible from HPWC.

Electrician originally planned to use aluminum cable between main panel and subpanel. I told him I would gladly pay the premium for copper. Lower resistance, more acceptable to future home buyer.

Also had the electrician run shielded twisted pair from HPWC to a reel in the ceiling. That will allow multiple HPWC to share the 100 Amp circuit.

HPWC dial set for 100 Amp service. Our Model S 100D gets its full 72 Amps. My friend's S 85D with dual chargers can pull a solid 80 Amps. The copper cable is slightly warm to the touch. Wife's P3D- gets its 48 Amps.

Every month or two there's a situation where relatively fast home charging makes life easier. Mids-afternoon last Saturday we decided to go to a distant barbecue place for dinner. I connected wife's 3 to HPWC and started charging. The car added enough range that we could make the trip without anxiety.

Live near Philadelphia, it's a Supercharger desert. There is no option to, "Stop by the SuperCharger for 20 minutes to add some range."

 

[m.c.b.]

All that has been said is good. Please turn the breaker OFF before upending the case and setting the rotary switch.
Opening the case needs a security torx that accommodates the pin in the center of the bit. To keep untrained hands out. Hint: tighten by hand not using a power tool.

 

[Rockct77]

I disagree. Set the HPWC dial to the circuit breaker/ampacity rating. The HPWC will limit charging to 80% of the rating. 40 Amp breaker with proper wire gauge? Set dial to 6. HPWC will only allow 32 Amps.

I had our electrician install 100 Amp breaker in the panel - he verified it was within panel limits. Then had crew run 2-gauge copper to a new sub-panel near the driveway. 100 Amp breaker in the subpanel, 2-gauge copper to the HPWC. That gives us options if we want to install additional HPWC or other charging arrangement. Subpanel with breaker counts as cutoff since it is visible from HPWC.

Electrician originally planned to use aluminum cable between main panel and subpanel. I told him I would gladly pay the premium for copper. Lower resistance, more acceptable to future home buyer.

Also had the electrician run shielded twisted pair from HPWC to a reel in the ceiling. That will allow multiple HPWC to share the 100 Amp circuit.

HPWC dial set for 100 Amp service. Our Model S 100D gets its full 72 Amps. My friend's S 85D with dual chargers can pull a solid 80 Amps. The copper cable is slightly warm to the touch. Wife's P3D- gets its 48 Amps.

Every month or two there's a situation where relatively fast home charging makes life easier. Mids-afternoon last Saturday we decided to go to a distant barbecue place for dinner. I connected wife's 3 to HPWC and started charging. The car added enough range that we could make the trip without anxiety.

Live near Philadelphia, it's a Supercharger desert. There is no option to, "Stop by the SuperCharger for 20 minutes to add some range."

it is rough around Philly for charging, but should be better by the end of the year at least according to the network expansion map. I was on a trip out Philly way a month ago and ended up having to drive to Claymont,DE to charge to make it back to Harrisburg charging station. No way I was going to hit up the station in the city that is in a pay parking garage.

 

[TexasEV]

it is rough around Philly for charging, but should be better by the end of the year at least according to the network expansion map. I was on a trip out Philly way a month ago and ended up having to drive to Claymont,DE to charge to make it back to Harrisburg charging station. No way I was going to hit up the station in the city that is in a pay parking garage.

I guess people value their time differently.

 

[Rockct77]

I guess people value their time differently.

they were both about the same time (not distance according to google traffic) just in the wrong direction. Philly one would have cost to park + people gave it a bad review. Claymont was at a Wawa so that made it even better to stop at a gas station and not get gas...

 

[Saibot]

So very few electromagicians install the entire circuit correctly as they often miss the 125% continuous rule, don’t pull the proper wire/cable gauge, jam an incorrect (some are interchangeable) manufactures 2-pole breaker onto the buss bar because that is all that is in the storage bin inside their truck, and almost never RTFM to properly set the rotory/dip switches.

Good-luck.

So, so true. I had to flog them a few times to get everything correct. Still wonder why I didn't just do it myself.
They initially had it set to 9 (48 amps) on a 50 amp circuit which was throwing errors/cancelling charging. Now on 9 with a 60 amp circuit and running fine.

 

[tg27]

This is sure a fun read even though I charge my SR+ with a 110 volt circuit. Great discussions.

 

[APD1080]

I'd get the work your electrician did independently checked. I had a LICENSED electrician that was on the Tesla recommended list install my Tesla wall charger before I had my solar panels and two powerwalls installed. The wall charger was to be set for 80 amps as they ran a new 100 amp line from my breaker box. When Tesla installed the solar panels and powerwalls I found my wall charger did not work correctly. The Tesla electrician determined the "licensed" electrician ran a 3 wire not a 4 wire so the grounds were not correct (there are 2 separate grounds required). The wall charger was smart enough to sense this. He also found the internal switches were incorrectly set, as other suspect yours might be. (my electrician did read the manual so not sure why a recommended electrician would be confused) The electrical code required a breaker disconnect within 5 feet if you have more than 50 amps. The "licensed" electrician installed a 100 amp breaker disconnect but put a 80 amp in the breaker box...go figure. The Tesla electrician confirmed they installed the correct gauge wires for the 100 amps (I'm an engineer so I like to have margin in my designs). The Tesla electrician set the internal switches to the correct setting and I had the "licensed" electrician come back and pull the missing ground wire, connect the missing ground as required, and install the correct breakers in my breaker box. I also called the owner and requested a 50% refund as their "licensed" electrician screwed up and that they were recommended by Tesla for wall charger installations. I got my 50% refund and everything has been working fine. Tesla really came through on this as it would have taken me awhile to go through the electrical wire diagrams and figure out the "licensed" electricians screw-ups.

 

[Niroc]

Op here. We set the switches and now are charging at 32 amps. Charging much faster now, yeah!

I did what Tesla directions told me; 40 amp circuit for the sr+. As a electric car newbie I hear about battery stress And degradation, I didn't want to take any chances and followed the rule book.

 

[ZOMGVTEK]

Glad you got it resolved. No worries on the charge current, 40A is plenty reasonable for both you and the battery. You could technically install a 10000A imaginary wall connector and the SR would still only charge up to 40A. The wall connector isn’t a charger, just a fancy extension cord with safety stuff inside. The charger is in the car, so it controls the show. But there’s no advantage to running a wall connector above 40A for your car anyways.