Charging issue with Tesla -> J1772

[solaskaze]

Hi all, I am wondering if anyone out there has had this problem, and how to fix:
- My Rivian will not charge @ 40amps, the max amount (via din setting) in my Tesla wall charger (Gen 2)
- It will choose 32amps when plugged in all by itself, BUT:

my particular setup:
- I have Two Gen 2 Tesla wall chargers, wired (twisted pair) together to distribute 40amps total, no matter the cars plugged in (I know this old-gen 2 wiring is uncommon)
-Multiple adapters available Tesla -> J1772 (all 48amp to 80amp, all fail as below):

If I plug in the Rivian first, then plug in a Tesla in the 2nd charger, the first charger halts charging and goes red, presumably as it sees > 20amps on the cable (i.e. the Rivian is ignoring amp changes)
If I plug the Rivian second, or start a charge with both vehicles plugged in (scheduled), it runs at ~20amps each as expected.

When I plug in the Rivian, it takes a long time to negotiate .... the light port briefly turns red, but then all green (all happy .... but with problems above)

Any ideas if this is a Rivian (Tesla protocol) v. Tesla Gen 2 v. ... the paired chargers issue?

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[Electrified Outdoors]

Just to confirm these are gen2 non WiFi units?

What brand adapter are you using?

Is the behavior the same. If you switch between the leader and the follower TWC?

 

[solaskaze]

These are gen 2. I ha

Just to confirm these are gen2 non WiFi units?

What brand adapter are you using?

Is the behavior the same. If you switch between the leader and the follower TWC?

That's right: Gen 2, uses twisted pair to talk to each other. I tried both brands: Lectron (48amp) and A2Z (80amp), although the latter I didn't try in every combo (e.g. intentionally cause the fault).
For sure, both exhibit a rather odd behavior even when charging is successful: the Rivian takes a long time to negotiate (blinking white light on the port), then is turns RED for maybe a second at most ... and then it turns green and begins charging. <==== is that normal for any Tesla -> Rivian connection.

Note that the protocol is somewhat? getting through, as: if I have both vehicles plugged in, both will charge @ 20amps.

Switching TWCs -- I haven't tried that, will do.

 

[Supratachophobia]

Maybe related, but will the Rivian obey the amperage signal sent by the UMC/HPWC? The HPWC is set via dip switches and the UMC gets it's orders from a diode in the adapter. At least that's my understanding.

 

[solaskaze]

Maybe related, but will the Rivian obey the amperage signal sent by the UMC/HPWC? The HPWC is set via dip switches and the UMC gets it's orders from a diode in the adapter. At least that's my understanding.

See my note above: I think so/partially, as if I have both vehicles plugged in (not charging) and THEN initiate a charge, they both charge @ 20 as expected. It could very will be that the Rivian is just too slow to notice the amperage change request, the TWC says "f--k off", and turns off. On the single car, high amperage case - it seems to be ignoring everything, and ... defaulting to "mobile" amps of 32amps??

I am reluctant to sever the twisted pair as an experiment, as it's wired deep inside the wall charger. While my circuit is rated for 60+ amps, I keep the max @ 40 because that's all I need overnight.

 

[SANZC02]

These are gen 2. I ha


That's right: Gen 2, uses twisted pair to talk to each other. I tried both brands: Lectron (48amp) and A2Z (80amp), although the latter I didn't try in every combo (e.g. intentionally cause the fault).
For sure, both exhibit a rather odd behavior even when charging is successful: the Rivian takes a long time to negotiate (blinking white light on the port), then is turns RED for maybe a second at most ... and then it turns green and begins charging. <==== is that normal for any Tesla -> Rivian connection.

Note that the protocol is somewhat? getting through, as: if I have both vehicles plugged in, both will charge @ 20amps.

Switching TWCs -- I haven't tried that, will do.

I have the Lectron 48 amp Tesla to J1772, when I have used it I always got the red for a few seconds and then turns green.

I do not remember seeing anything higher than 40 amps but I know I was getting 40 amps at a Tesla destination charger at a hotel in FL.

 

[Electrified Outdoors]

There is a leader and a follower in Tesla power share both for the Gen 2 and the Gen 3. The leader will have two green LED when you power it on and the follower only has one.

It is normal for the Rivian to blink red before a charge session starts on TWC. I have two in my garage on a power share. Mine are gen 3 and I have 60 amps allocated. One is a J1772 TWC and the other a standard Gen 3. On the standard Gen 3 I have used both TeslaTap Mini and a Shockflo Tesla to J1772 adapter.

Mine works flawless. 48 amps in single or 30 amps if both are charging. I wonder if you plug in two non Tesla EV if the problem will be the same.

Swap chargers and if it still an issue possibly try without a Tesla EV. I'm not too familiar with the Gen 2 other than how they are configured.

Mainly gen 2 use dip switches and comm cable vs gen 3 which uses firmware and wifi to do provisioning & group power management.

 

[solaskaze]

Update: Tesla Gen 2 (w/ wired pairing): it's just broken. Seriously broken.
So: I updated completely to Gen 3 Tesla UHC + standard Gen 3.
Physical HW: works flawlessly, easy to insert (Rivian), much happier.
Power sharing: it's still broken! The good news is that this is - still - a SW issue. The issue is still a moving firmware target, so: my recommendation is go all in on UHC everywhere, else all in on standard, don't mix.

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