Tesla blown fuse with UMC after rain

Hi everyone - i just bought a model s from december 2018 owned the car for a week, i use to charge my car with my 3 fase orginal tesla charger which worked fine for 5 days. Now (i don't know if its a coincidence or not after heavy rain) the charging on 3 fase UMC on 16A is short circuiting but the normal Schuko plug (charging at 13A) works. Both worked previously.

What i did to troubleshoot is:

1. Fully charge the car and reconnect the UMC charger to the car when its not charging (works)
2. when it starts to charge it directly short circuit my (32A) connection,
3. tried to lower the Amps which had no effect

Does anyone know what might be the issue, the car doesnt mention any issue just reports "no power charging stopped "

 

[davewill]

The obvious thing is to troubleshoot whether the issue is the car, your UMC, or your circuit. From what you describe, it could be any of them. Can you borrow other UMCs and/or cars to test with?

 

[Zuikkis]

Or visit some type2 charger to see if it charges at full power, and all phases .

Most likely it's a fault in the UMC. Tesla changed the UMC to single phase in newer cars for a reason; the three phase version simply has too much electronics in too small enclosure. It will eventually overheat and break.

I have opened several and even managed to fix a few. Big problem are the flat "abiko" connectors used to connect wiring to the circuit board. Those are really on the limit with 16A..

Also the internal relays are rated at 16A max, so also those are constantly on the limit. One UMC had a hole melted to the side of the relay, probably because of arcing caused by bad contact.

Anyway; if your UMC still works in single phase, just use it like that and get a real EVSE for three phase charging. That is the setup any newer Tesla owner has to go anyway since Tesla dropped the 3phase UMC..

 

[Droschke]

Tesla changed the UMC to single phase in newer cars for a reason; the three phase version simply has too much electronics in too small enclosure. It will eventually overheat and break.

Is the three-phase only for Europe or you know if the U.S. ones also were (are) three-phase?

 

[Zuikkis]

Is the three-phase only for Europe or you know if the U.S. ones also were (are) three-phase?

It's Europe only.

In Europe we typically have only perhaps 25A or 35A main fuses in our homes, but there's three phases so you can draw 3*25A with 25A fuses. Tesla UMC (gen1) is 3*16A max, which at 230V equals 11kW of charging power. Also UMC gen1 allows the phases to be combined which then allows 1*32A charging (7kW).

Euro UMC gen2 only supports this 1*32A (7kW) mode. This is usually useless for home use since you can only draw 16A from a regular wall outlet.

In the US, you don't have three phase electricity usually, but single phase with very big amps (40A or 80A etc).. UMC gen1 supports 40A (about 9kW?) but UMC gen2 dropped this to 32A (same 7kW as euro-UMC-gen2)..

I believe that starting from gen2 UMC's are the same device for entire world, just different wall plug adapters and different car side connector.

So, even in the US version had the power dropped in gen2, from 9kW to 7kW.. But 11kW three phase is absurd, the separate phases take so much room. Yet the container is same size as the US version. There's three relays vs only single relay in US version, etc.

 

[Droschke]

It's Europe only.

In Europe we typically have only perhaps 25A or 35A main fuses in our homes, but there's three phases so you can draw 3*25A with 25A fuses. Tesla UMC (gen1) is 3*16A max, which at 230V equals 11kW of charging power. Also UMC gen1 allows the phases to be combined which then allows 1*32A charging (7kW).

Euro UMC gen2 only supports this 1*32A (7kW) mode. This is usually useless for home use since you can only draw 16A from a regular wall outlet.

In the US, you don't have three phase electricity usually, but single phase with very big amps (40A or 80A etc).. UMC gen1 supports 40A (about 9kW?) but UMC gen2 dropped this to 32A (same 7kW as euro-UMC-gen2)..

I believe that starting from gen2 UMC's are the same device for entire world, just different wall plug adapters and different car side connector.

So, even in the US version had the power dropped in gen2, from 9kW to 7kW.. But 11kW three phase is absurd, the separate phases take so much room. Yet the container is same size as the US version. There's three relays vs only single relay in US version, etc.

Tnx so much.