Problem charging at 1.4 Kw on a cold day

[Dilly]

It’s been reported on the Myenergi forum that trying to charge minimum at rate on a cold day at 1.4 kw with a Zappi may fail.
This is down to the Tesla. Not sure if other chargers may be affected.

the problem has been (unofficially) recognised by Tesla.

I haven’t had an issue, but mine is garaged,

the article is here:

Tesla - Issues trying to charge when cold

 

[Cardo]

This will certainly be an interesting one to watch out for. We’ve just picked up our M3, so I’m braced for the Tesla peculiarities. I’ve been spoiled with my BMW i3, which just works.

 

[Dilly]

This will certainly be an interesting one to watch out for. We’ve just picked up our M3, so I’m braced for the Tesla peculiarities. I’ve been spoiled with my BMW i3, which just works.

I think we’re talking really low temperatures. Mine gets down to 2 or 3 degrees in the garage when it’s zero or less outside and doesn’t prevent charging.

 

[Cardo]

I think we’re talking really low temperatures. Mine gets down to 2 or 3 degrees in the garage when it’s zero or less outside and doesn’t prevent charging.

I had planned to keep the M3 in the garage, however the Mrs doesn’t like getting the car in and out of there and the doorway is too narrow for summon to work! So driveway it is...

 

[Cloggie]

I think we’re talking really low temperatures. Mine gets down to 2 or 3 degrees in the garage when it’s zero or less outside and doesn’t prevent charging.

My car charged with with -10 a few weeks ago (not on a Zappi). If people in the US and Canada can charge their cars when the charge port freezes, I think we'll be ok here

 

[Glan gluaisne]

IIRC, it's been reported previously that charging at the minimum current in IEC 61851 (6 A) might be a bit hit and miss. I think the recommendation was to use 8 A as the minimum, in order to avoid problems.

FWIW, this is not a Tesla-unique issue, as other EVs also tend to play up down at 6 A. All EVs tend to decrease in charging efficiency a lot as the AC charge current decreases, as the fixed losses in the charger(s) stay much the same irrespective of charge current (the overhead of the car being powered up, etc). The Zoe barely charges at 6 A I believe, as its charger efficiency seems to get far worse as the current decreases, by virtue of its slightly unusual design, using the motor windings as the switched mode charger inductance.

 

[MrBadger]

One of the (iirc open source) charge point projects has removed the ability of their system to charge <10A due to battery issues. Its been a while since I read this but cannot be sure of the source but it may have been the one that allowed variable charging rates on the Tesla Wall Connector - New Wall Connector load sharing protocol. I got the impression that the guy really knew his stuff and it was a genuine concern about charging at low charge rates and battery health - more than just the inability to charge at low rates when cold.

edit - think this is the reference New Wall Connector load sharing protocol

 

[AndrewGR]

I don’t usually have much solar power to spare during the winter but my Zappi has been happily charging at rates down to 1.4kW during the recent sunny but cold weather. It’s not very efficient but it’s free so I’m not worrying!