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UMC charging limited to 32A in Canada?

Discussion in 'North America' started by nwdiver, Jul 25, 2017.

  1. nwdiver

    nwdiver Active Member

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    I saw a post on Facebook that charging with a UMC in Canada has been limited to 32A... can anyone confirm or deny this?
     
  2. Paul Carter

    Paul Carter Active Member

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    Yes new UMC 14-50 Canadian adapter only allows 32 amps pull. It even has its own part #.

    See Tesla — NEMA 14-50

     
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  3. nwdiver

    nwdiver Active Member

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    Surprised it's not geo-locked... I can see a black market in Canada for US adapters :cool:

    Getting a HPWC would almost double your charging speed in Canada....
     
  4. GSP

    GSP Member

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    Canadian 14-50 adapters were 40 Amp for the Roadster and early Model S. The 32 A limited adapters appeared 1-2 years ago in Ontario. There was discussion about it here at TMC. I think 32 Amps might still only be required in some parts of Canada, not all.

    In the US, you can select either the US or Canada version of the 14-50 adapter when you order online from Tesla. I ordered the Canada version to use with a 14-50 stove outlet at my vacation cottage. It has a 40 Amp breaker and wiring. At first I manually reduced the current to 32 Amps. With my new Canadian adapter it is automatically capped at 32 Amps, providing insurasnce against software glitches or forgetfulness.

    GSP

    PS. I now have UMC adapters from Tesla with limits of 12, 16, 24, 32, and 40 Amps (for circuits rated at 15, 20, 30, 40, and 50 Amps). With homemade adapters to convert these to different outlet types, as needed, I am ready for just about any charging opportunity. :cool:
     
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  5. animorph

    animorph Member

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    Now you need to tell us how those current limits are communicated to the UMC. I haven't seen info on that yet.
     
  6. GSP

    GSP Member

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    @animorph,

    The UMC adapters have resistors built into them. The resistor value depends on the max safe current for that type of plug (80% of circuit breaker rating).

    The UMC reads the resistance and sends the appropriate J1772 pilot signal to the car.

    GSP
     
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  7. animorph

    animorph Member

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    That's what I thought, but I haven't seen anyone describing how to make an adapter with the correct resistor value.
     
  8. GSP

    GSP Member

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    That is why I bought the UMC adapters from Tesla. To make these adapters the resistance values can be easily read with an ohmeter, and TMC members have done so and posted the values here on TMC. However it is nesessary to reverse engineer Tesla's proprietary interface between the UMC and adapter, then pay for tooling to injection mold your own adapters. That said, there is a member doing just that and selling adapters.

    I just use Tesla's adapters to get the correct current limit, and make my own adapters to change the plug type when necessary. For example, to use TT-30 outlets at RV parks, I bought a TT-30 plug and cord from Amazon, and a 14-30 surface mount outlet. I wired the cord to the outlet, and use Tesla's 14-30 UMC adapter to connect the UMC.

    GSP
     
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  9. Plugsuvohio

    Plugsuvohio Member

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    There are other issues that are likely part of this. I consult for a small company developing a specialty EVSE, who happened to be the original Roadster mobile cable designer and manufacturer. (One of the originals on their conference room wall). We are concentrating on some specs outside the US, but the US standards just changed December 2016 and went into the 2017 NEC. The safety community and EV people have been in a struggle for years on what limits should be on cord and plug connected EVSE. They even played with the classification terminology. Mobile vs stationary for example. Stationary means it can have a plug with high amp limits, but the unit has to be mounted in a "semi-permanent" way which is only meant to be disconnected in a situation such as moving it to a new house. It all relates to overheating as connectors and sockets wear on the utility side of things. And, people using extension cables, despite all the warnings have made it worse. As I read the code now, the 40A UMC could not pass the UL standard (it it met the standard in the first place. I think Tesla pretty much did what they wanted to and didn't care if people would even notice the lack of the UL mark. Above 32A they want hard wired EVSE units.
     

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