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220V charging (technical) question

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Hi there!
I am having issues with my 220V charger (the 50A wired one, not the 70A wall-mounted one). When I connect it up (wall, then car - not that it matters, I get the same problem either way) the car goes from white, to blue, to red. The light on the charging cable goes from solid green to 3 flashes of green, then one red (continuously). I contacted Tesla yesterday and they downloaded my logs and are reviewing them.

We have two-phase power coming into our house panel (2 x 110V and a neutral - no separate ground.) There are four wires going to the NEMA 14-50 (2 hots, ground, and a neutral.) I traced them back to the panel and both the ground and the neutral go to the ground bar (like all of the other wires coming in.) I checked the voltage at the receptical, and there is 120V to ground, 120V to neutral and 240V between the hots (exactly what I expected.)

When I called Tesla, they told me the charger is very sensitive to voltage differences and fluctuations. I am wondering if the charger needs the ground and neutral to be completely separate? If so, I am screwed because there is no way I am running a separate ground to the panel and separating all of my neutral and ground wires.

Does anyone else have a similar wiring setup (ground and neutral are shared?) I am told this is common in Florida (at least it was in 1985!)

thanks,
Jordan
 
It seems to charge fine with 12oV (thank goodness!)

I believe I have the new UMC (it looks like the one advertised currently at teslamotors.com).

I'll try the short wire trick now!!

I don't have a UMC manual in my bag of tricks - can you point me to one online?

thanks very much to everyone for your help!

Jordan
 
I installed the Nema 14-50 and by code you should have a separate neutral and ground and they should terminate on the ground bar inside the breaker box. I cannot inderstand why that is the code as a jumper wire should do the same thing. And make sure you have a non GFI 50 amp breaker. If you are still having a problem i would check with a friend/neighbor or go to a nearby trailer park and test out the cord. If you have the same problem then it is likely the cord.

Also be sure the 240 is measured from the left to right blades and you get 120 from the blade to neutral and to ground.
 
I just hope that you don't ever get the same issue that I did a while back. (PEM line fuse.)

The neutral isn't connected to anything on the UMC. The UMC needs Ground + 2xHot. So, I'd first check the voltages that you are receiving.

Are you receiving 250v+?
Have you done a GFCI test on the UMC?
 
PEM line fuse? What were the symptoms?

The outlet is wired correctly (as you described)
The breaker is not a GFI.
I get around 240V across the two hots and 120V between each hot to ground or neutral.

How do I do a GFCI test on the UMC?

thanks for all of your help and suggestions,
Jordan
 
PEM line fuse? What were the symptoms?

The outlet is wired correctly (as you described)
The breaker is not a GFI.
I get around 240V across the two hots and 120V between each hot to ground or neutral.

How do I do a GFCI test on the UMC?

thanks for all of your help and suggestions,
Jordan

I realize it is a holiday weekend, but has Tesla come out and inspected things? Have they offered to bring out a second UMC for testing?
 
Thanks very much for the manual.

One thing I noticed: I can change the charging current (via the touch screen) when the car is charging at 120V. I don't get the chance to change the current setting for 240V (the light goes from white to blue to red and the touch screen starts to flash a warning before I can get to change the current setting.)

Someone mentioned PMCI test and a PEM fuse. I did not see either mentioned in the manual. Can you shed some light on this?
 
I never change the current while the car is charging. (Don't know if others advise this?). If you are plugged in, but the slide switch is back (away from the car body) you can change the charge settings regardless of charge type (this also works just with the charge port door open, but not plugged in). Change the settings then slide the lock switch forwards to initiate charging.

When you get the red light normally just hit the reset button on the UMC. I'm not sure what Petefish meant by GFCI test on the UMC. AFAIK, the PEM line fuse is not something you can deal with yourself.

Good advice from dhrivnak above: "...check with a friend/neighbor or go to a nearby trailer park and test out the cord. If you have the same problem then it is likely the cord." BTW, plugshare.com may show you someone locally with a NEMA 14-50 who'll let you try your UMC cord.
 
Thanks for pointing out plugshare - I've added myself - 120V for now ;-) There are a few J1772 connectors around. That is a little confusing - the only 220V option on plugshare is the J1772. I guess I need to ask them what kind of 220V connector they actually have.
Its raining here now, but will call someone nearby later.

I have tried resetting the cord. Neither of the two lights over the buttons light up - just the top one goes from green to flashing green/red.
When I press the reset button, the fault light on the cord briefly flickers on then remains off.