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Might have a fried UMC?

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So I charged overnight the other evening, but when I went to leave in the morning I noticed the car hadn't fully charged. Drat. Checked the OVMS messages and noted that it was getting #954 DMC FW: Line Voltage lost Sync and #981 DMC FW: Bad State Transition alerts periodically throughout the night (as it tried to restart the charge, I guess).

Tried to restart the charge manually, it started but stopped after about 5 minutes with the same alerts.

Fast forward a few days...

Came home from a business trip tonight and the car had fully charged using the 110v cable. Tried to plug in the UMC and the UMC is now just flashing green (8 slow flashes then continuous fast flashes). Test does nothing, reset flashes both red and green.

My nearest service center is 150 miles away. Their Roadster tech is over in China and won't be back until mid to late November (I am also due for my annual).

Anyone have any thoughts about the UMC? I will probably give it a shot in another location, but i checked the connections for the NEMA 14-50 and everything was tight so I don't think it's the wiring.

If it is fried, what would you do? Model S wall connector plus Can II? Model S mobile connector plus Can II? One of the Model S connectors with the Roadster head on it (if this is even possible)?
 
I'd get a J1772 EVSE plus a Can I - out of the two adapters, I use that one much more. And then I'd spring for the Can II just to have it with me for road trips. But if you put a J1772 in your garage, any EV visitor can charge at your house, not just Tesla visitors.
 
Don't make any assumptions that its fried until you've tested at another location and also on another Roadster. I have to say the UMC in my experience is quite flakey, not like my MC240 which has always been reliable. The MC240 is my dedicated home charger and gets used almost every day.

I had my UMC do a similar thing, was charging at an off location, came back and I was like what the hey, where are my miles!?!? Looked at the UMC and it was in an odd state. Believe the amber light was on. Had to cycle the darn thing, unplug it, replug it, reset it, and re-initiate the charge from the car again. Started charging. No feedback what so ever from the thing to understand what its upset about.
 
Unfortunately the UMCs don't have a long lifespan. I've gone through one and when I located a second one, decided not to use it for daily charging. I now charge off a Clipper Creek HPC that I bought from another Roadster owner (those things are BEASTS!) and have the UMC available for road trips or backup.
 
Unfortunately the UMCs don't have a long lifespan. I've gone through one and when I located a second one, decided not to use it for daily charging. I now charge off a Clipper Creek HPC that I bought from another Roadster owner (those things are BEASTS!) and have the UMC available for road trips or backup.

I agree about the lifespan of the UMC. I'm thinking about picking up a JuiceBox (set for 70-80 amps), then adding some connectors to it to break it down into manageable components that tuck away behind the driver's seat and trunk. I'm worried about my UMC failing when I'm out on the Road and then dependent on the 110V mobile charger. I only used my UMC a handful of times and already lost confidence in it.

I also have the ClipperCreek HPC. Didn't have a chance to install it, need to upgrade my home service to pull the 70AMPS. As Henry mentioned, that cable is huge and they didn't skimp on the copper back then! More copper makes it more efficient and less energy loss through heat.

Actually I was wrong about no failures on my MC240 charger, I had a mechanical failure! Right where the wire goes into the MC240 Roadster connector, there was a clamp cinch ring the kept the cable rubber covering and insulation from pulling out of the Roadster connector. I took the Roadster connector apart right there and found it was the stupid clamp that undid from all the heavy use of charging/unplugging from the Roadster. I put a stainless hose clamp in there as its replacement so no more of that nonsense. It still has not let me down without a charge. If it did it was user error where I failed to engage the charge switch on the Roadster connector.
 
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I also have the ClipperCreek HPC. Didn't have a chance to install it, need to upgrade my home service to pull the 70AMPS. As Henry mentioned, that cable is huge and they didn't skimp on the copper back then! More copper makes it more efficient and less energy loss through heat.

I was motivated last summer when all the Roadsters and Model S owners were at the house for the bbq before TMC Connect. I needed as many charging options as possible!
 
...If it is fried, what would you do? Model S wall connector plus Can II? Model S mobile connector plus Can II? One of the Model S connectors with the Roadster head on it (if this is even possible)?

Adapters are great when you're out and about but IMO not very convenient for home use. I like to get out of my car, grab that connector and plug it in with one hand without losing my stride. I don't want to think about "now where did I leave that adapter" especially on a trip and you suddenly have this sinking feeling you left it on the end of your charge cable at home and it's not in between your seats anymore.

So my vote is for a Clipper Creek charger with a Roadster connecter installed on the end of it. Yes that's possible, but it's not the cheapest option.
 
I just got done installing the 100A service to my garage for the Clipper Creek 70A Roadster charger, haven't gotten to test it yet since my car is up North for another week but eager to try it out when it gets back. No kidding on the wires! Its #4 wire in the cable from the charger to the vehicle! #2 or #3 copper is best for the 100A service plus you should have a fused 100A disconnect between the main panel and the charger too... I did all the install myself and it was tough working with those fat wires.

I think it is the "correct" way to solve the home charging issue, it is the most robust and elegant system. And those Clipper Creek units can easily be swapped to J1772 format for future EV's that may show up in your garage! Plus, whats better than getting 70A charge rate? Not much, I believe the charging system is also most efficient when at 40A and above!
 
I just got done installing the 100A service to my garage for the Clipper Creek 70A Roadster charger, haven't gotten to test it yet since my car is up North for another week but eager to try it out when it gets back. No kidding on the wires! Its #4 wire in the cable from the charger to the vehicle! #2 or #3 copper is best for the 100A service plus you should have a fused 100A disconnect between the main panel and the charger too... I did all the install myself and it was tough working with those fat wires.

I think it is the "correct" way to solve the home charging issue, it is the most robust and elegant system. And those Clipper Creek units can easily be swapped to J1772 format for future EV's that may show up in your garage! Plus, whats better than getting 70A charge rate? Not much, I believe the charging system is also most efficient when at 40A and above!
If it's like tesla original one at least only two hots without a neutral
 
I agree about the lifespan of the UMC. I'm thinking about picking up a JuiceBox (set for 70-80 amps), then adding some connectors to it to break it down into manageable components that tuck away behind the driver's seat and trunk.

A portable Juicebox is only as good as the amperage it can receive. I am not aware of any easily accessible and routinely common 80amp plug ins. That would limit your UMC to about 40 amps as a portable unit. Upgrading the firmware to allow 80AMPs is for full time installed units.

I agree that the Juicebox can indeed be upgraded to 80 AMPs, as I'm having that done. The problem is that the Juicebox is only as good as its power source, and there are no 80AMP plugs at campgrounds. You will be limited to a maximum of maybe 40 AMPs tops.

Best,

T
 
Adapters are great when you're out and about but IMO not very convenient for home use. I like to get out of my car, grab that connector and plug it in with one hand without losing my stride. I don't want to think about "now where did I leave that adapter" especially on a trip and you suddenly have this sinking feeling you left it on the end of your charge cable at home and it's not in between your seats anymore.

So my vote is for a Clipper Creek charger with a Roadster connector installed on the end of it. Yes that's possible, but it's not the cheapest option.

Not being that confident in my abilities to do this (although I did install my NEMA 14-50), do you have thoughts on how to get this done? Local electrician? Do you think CC would do it if I sent them the connector from my (potentially faulty) UMC? Is it fairly straightforward and I could do it myself?

If I did go the EVSE + adapter would you recommend the Clipper Creek or a Model S connector?
 
Not being that confident in my abilities to do this (although I did install my NEMA 14-50), do you have thoughts on how to get this done? Local electrician? Do you think CC would do it if I sent them the connector from my (potentially faulty) UMC? Is it fairly straightforward and I could do it myself?

If I did go the EVSE + adapter would you recommend the Clipper Creek or a Model S connector?

I believe Henry meant you should purchase the Clipper Creek HPC that was sold for Roadsters (with the Roadster head installed). It looks like they are still available in the TM store: Tesla Gear Shop Roadster High Power Wall Connector , but pretty pricey. (They were definitely built to last and you won't find any complaints regarding failures on this forum.)

I bought mine used for substantially less $, but you don't see many offered for sale.
 
They do pop up on ebay. Missed out on two that went for $600-700, the $600 was brand new and didn't get bid higher in the end. I bid but already have one hence why I didn't go higher. There's also a 60 AMP clipper creek with the 60 amp adapter for sale that's refurbished on ebay for $600. That one however has a dinky charge cable and a j1772 end I'd swap out.

@TOBASH, thanks about the JuiceBox update. Right, NEMA 14-15 will be the highest at 50AMPS (realistically 40) while the 80 amp woudn't be all to portable just due to the cable size alone to carry 80amps!
 
They do pop up on ebay. Missed out on two that went for $600-700, the $600 was brand new and didn't get bid higher in the end. I bid but already have one hence why I didn't go higher. There's also a 60 AMP clipper creek with the 60 amp adapter for sale that's refurbished on ebay for $600. That one however has a dinky charge cable and a j1772 end I'd swap out.

@TOBASH, thanks about the JuiceBox update. Right, NEMA 14-15 will be the highest at 50AMPS (realistically 40) while the 80 amp woudn't be all to portable just due to the cable size alone to carry 80amps!
I'm not convinced the two on ebay were legitimate. I thought they were the same seller, but, looking back, they were two different sellers. With the same location, stock photos, no feedback, and other items listed. One now had negative feedback because he didn't follow through on another transaction. Too many red flags. I've seen a real one sell for $1,300 recently, but I did get mine for less than that.
 
The first one looks legit, as if someone bought a house with the charger installed, had it removed, and sold it on ebay. Most likely someone who's never used ebay before. One review was just posted, I think for the charger sale since there were not reviews before the sale:

Tesla Car Charger | eBay

The one that was brand new is a little odd, but who knows if it was a true seller or not:

Tesla Roadster High Power Wall Connectorâ€￾ | eBay
 
Tried to plug in the UMC and the UMC is now just flashing green (8 slow flashes then continuous fast flashes). Test does nothing, reset flashes both red and green.

I am sorry to say I bought one on eBay last year that I thought was working, but just flashed green when I plugged it in. Reset did nothing. It ended up being a $500 paperweight. I gave it to TonyWilliams to troubleshoot, but he could not repair it. Last I heard, he was going to modify it to work with OpenEVSE, but I think he started working on other more important projects instead.

From what I've read, those Roadster UMC's had very poor reliability. I like the Clipper Creek J1772- to CAN option or Model S to Roadster CAN options. I think the Model S mobile charging cable is only $650 compared to $1500 for the Roadster one, although you have to factor in the cost of the CAN, of course.
 
So I tested the UMC at another location with the same results (still flashes green and no charging).

Based on the feedback here (and some PMs with Henry - THANKS!) I have decided to go with an OpenEVSE with the Roadster connector cannibalized from the original UMC.

Two questions:

1) Anyone have a recommendation for a NEMA 14-50 plug and wiring that they have used (I might do up to 20')?
2) Any advice on removing the Roadster connector/cable from the UMC, or just cut it off as close to the box as I can?
 
1) Anyone have a recommendation for a NEMA 14-50 plug and wiring that they have used (I might do up to 20')?
2) Any advice on removing the Roadster connector/cable from the UMC, or just cut it off as close to the box as I can?

I can't recommend anything personally, but maybe mitch672 can. He seems quite proficient with OpenEVSE:

40A OpenEVSE w/Model S connector

TonyWilliams over at Quick Charge Power also seems to sell some good quality 40 amp cable, but he doesn't seem to specify the lengths:

EV (Electric Vehicle) Charging Products

J1772 Cable


I bought a 14-50 receptacle from him for $5.99, which was a lot cheaper than Home Depot.