New UMC?

[Phillip L]

I actually did this, but bad things didn't happen... I just popped the breaker. I was at a rental property I owned, and just pulled the stove out and plugged in to charge my car.

This is where I learned that many (most? all?) stove 14-50 outlets are wired up with 40 amp wiring and breakers. I've done the same thing (with the stove) at a friend's cottage, but now always lower the charging current to 32 amps or less.

That is exactly what I did this summer. Had to go get some new fuses for the stove breaker (is an old farmhouse with fuses rather than breakers) then I did exactly what you did .... Dialled down the current to about32 amps. I guess this thread answers my question indirectly. I bought the NEMA 14-30 adaptor before it became unavailable. It should work fine with the new UMC.

 

[DMC-Orangeville]

It's not Tesla thinking it's not safe to use a UMC at 40A or a limitation of the UMC itself. The problem is that there apparently are 14-50 sockets with 40A breakers allowed in Canada.As this setup can only deliver 32A, Tesla is changing the UMC so that fire/breaker tripping is not a possibility. If you're using a UMC connected to a 14-50 socket fed with the right gauge wire and a 50A breaker, there is no issue drawing 40A.

On a 40 amp breaker being allowed for NEMA 14-50 - not really true....unless it is specifically for a range. Please see my response from the Electrical Safety Authority (ESA) New UMC? - Page 3

Of note, his opinion: Today, a 14-50R receptacle that is NOT for a range, MUST be connected to a 50 amp overcurrent device.

 

[RAM_Eh]

As an electrician and this is my take on the subject.

a 14-50 plug is rated for 80% 0f 50A= 40 A. Wire size is not de-rated in the CEC or the OEC...# 8 wire can safely handle the 40A. Breakers rated for 40A do not need to be de-rated since the frame is probably rated for much more.

I believe the issue to be with the connector orthe UMC not the cable, breaker or receptacle. We are missing a piece of information here. I think its an approval issue.

 

[mknox]

a 14-50 plug is rated for 80% 0f 50A= 40 A. Wire size is not de-rated in the CEC or the OEC...# 8 wire can safely handle the 40A. Breakers rated for 40A do not need to be de-rated since the frame is probably rated for much more.

... 80% or 40 amps for what the code defines as "continuous loads" such as an EV charging. A 40 amp breaker will trip if you put a continuous 40 amp current through it after about 5 - 10 minutes (in my personal experience).

I believe the issue to be with the connector or the UMC not the cable, breaker or receptacle. We are missing a piece of information here. I think its an approval issue.

I agree. The ULc certification will cover the device, not what it's plugged in to. I suspect there is a piece we're missing here too.

 

[Paul Carter]

I've talked to someone yesterday who is a contributor to the Canadian Electric Code and very involved in electric vehicle portion. There is at least no new codes coming up that could explain this. So we can eliminate that as a missing piece.

We did come up with a theory that either there are issues with a high number of improper usage on 40 amp circuit (and of course that's a big safety concern) or providing a device that allows more people to easily use 40 amp circuit at 80% continuous (which is the 32 amp). The latter might easily explain the pilot.

 

[dmckinstry]

It's not Tesla thinking it's not safe to use a UMC at 40A or a limitation of the UMC itself. The problem is that there apparently are 14-50 sockets with 40A breakers allowed in Canada.As this setup can only deliver 32A, Tesla is changing the UMC so that fire/breaker tripping is not a possibility. If you're using a UMC connected to a 14-50 socket fed with the right gauge wire and a 50A breaker, there is no issue drawing 40A.

A 50A breaker isn't that expensive. I live in the U.S. so it may not matter to the Canadians, but I've never had overheating with my UMC or 14-50 adapter. Either the original adapter or replacement.

 

[mknox]

A 50A breaker isn't that expensive. I live in the U.S. so it may not matter to the Canadians, but I've never had overheating with my UMC or 14-50 adapter. Either the original adapter or replacement.

It's not that simple. NEMA 14-50 outlets can be legally wired up, in both Canada and the US, to 40 amp breakers with 40 amp rated wiring. You can't just pop out the 40 amp breaker and replace with a 50 amp one because the wiring may be under-sized. As much as this is an issue in Canada right now, there is no reason it couldn't be in the US as well (as far as I can tell).

- - - Updated - - -

I got mine today and did a quick comparison...

Anyone know if everyone in Ontario will be getting a new one? Should I be expecting a visit from the FedEx guy/gal?

 

[sataponw]

I got one this week. Hasn't had a chance to send the old one back yet.

 

[Cottonwood]

Has anyone tried sending back the old UMC with the new 32-Amp adapter? That way you could keep the new UMC with a 40-Amp, 14-50 adapter. Just thinking...

 

[Canuck]

Not legally, no. Tesla made "a reasonable effort" to ensure your safety. So they are off the hook now. Should your property catch fire (god forbid!) you can no longer sue them. That's what it is all about.

P.S. I'm returning the old one.

You could still sue them. If the fire started with the old one, Tesla would have a strong defence but could still be found liable. If it started with the new one, the fact that you never sent the old one back is irrelevant.

Anyone outside of Ontario get one?

 

[SluyterCapital]

Too funny! I think the fact that you acknowledge receipt of the charger cable in your post, while identifying your VIN number 25679 in your signature is all the proof that Tesla needs for a Proof of delivery. Really..... too funny.

I also received mine this morning from Fedex. They just dropped it at my door and didn't wait for a signature so there is no proof they actually delivered it to me.

When I purchased the car my planning assumed 40A charging at home. If Tesla thinks the current UMC is not safe to charge at 40A then they can provide me another "safe" solution that charges at 40A or above (e.g. HPWC) at no cost.

I won't be returning anything and will not have anything in my car when I go for service.

 

[hemants]

Leave the new one in the car. End of story.

 

[mnx]

Got mine in the mail today.

There is no way I'm parting with my old 40A capable adapter.

 

[mknox]

There is no way I'm parting with my old 40A capable adapter.

I actually have 2-40 amp NEMA 14-50 adapters. Quite a while ago, they sent me one and asked for the old one back (oops... forgot to send it back). I believe the newer one has some sort of thermal fuse in it. Still haven't got my whole new UMC set yet.

 

[Forty Creek]

I actually have 2-40 amp NEMA 14-50 adapters. Quite a while ago, they sent me one and asked for the old one back (oops... forgot to send it back). I believe the newer one has some sort of thermal fuse in it. Still haven't got my whole new UMC set yet.

Ha... maybe they're still ticked that you didn't return the old 14-50

 

[mknox]

Ha... maybe they're still ticked that you didn't return the old 14-50

Well, I found my replacement UMC today when I got home from work. I tested my assortment of now 3 14-50 adapters on both cord sets: The original one with the black backside as well as the newer one with the grey backside both charge at 40 amps on either cord set. The new 14-50 adapter with the white backside (that came today) charges at 32 amps on both cord sets. So it looks like it's all about the adapter. I can't say for sure, but other than the new ULc label on the UMC it seems the same to me. Not sure why they just didn't send out new adapters like they did last time.

 

[mnx]

Not sure why they just didn't send out new adapters like they did last time.

Trying to trick us into using the new one I suspect.

 

[Kalud]

Well, I found my replacement UMC today when I got home from work. I tested my assortment of now 3 14-50 adapters on both cord sets: The original one with the black backside as well as the newer one with the grey backside both charge at 40 amps on either cord set. The new 14-50 adapter with the white backside (that came today) charges at 32 amps on both cord sets. So it looks like it's all about the adapter. I can't say for sure, but other than the new ULc label on the UMC it seems the same to me. Not sure why they just didn't send out new adapters like they did last time.

Must be the internal circuit that needed some changes for ULc certification.

Could be the 30A relay. They were using a T92S7D12-24 relay from TE Connectivity.

Source

 

[Doug_G]

Must be the internal circuit that needed some changes for ULc certification.

Could be the 30A relay. They were using a T92S7D12-24 relay from TE Connectivity.

Source

Very possible. The relay is spec'd for 40A, but certified for 30A. There may be other components that have similar limitations though.

 

[dj905]

Well, I found my replacement UMC today when I got home from work. I tested my assortment of now 3 14-50 adapters on both cord sets: The original one with the black backside as well as the newer one with the grey backside both charge at 40 amps on either cord set. The new 14-50 adapter with the white backside (that came today) charges at 32 amps on both cord sets. So it looks like it's all about the adapter. I can't say for sure, but other than the new ULc label on the UMC it seems the same to me. Not sure why they just didn't send out new adapters like they did last time.

Interesting. When I used the new 14-50 adapter on the old cord set, it presented with an error and the charging port glowed red. The old 14-50 adapter on the new cord set seemed to work fine at 40amps.