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Garage Wiring Fire

Tommy

Member
Mar 3, 2010
882
3
The great OC
The UMC is easier to install than the HPWC. Besides the HPWC 2x's cost, there is also the extra cost of installing a disconnect switch which is required for the HPWC due to it being hard wired. For someone with an existing 240v outlet in the garage, the UMC makes perfect sense, provided he/she doesn't plug/unplug excessively and both wiring and outlet are up to par.

For my own installation I used a Hubbell commercial grade receptacle HUBBELL HBL9450A AC Receptacle NEMA 14-50 Female Black 125/250 Volt 50 Amp - Our Item #: 8694, Category: NEMA 4-Wire Receptacles : StayOnline
easily 4 times the cost of the receptacles the big box stores sell. I looked at both, the Hubbell is constructed better. I also used 6 gauge wire and an over-sized outlet box so the wires wouldn't have to be crammed in. I did this so I wouldn't worry about marginal parts being the reason for a fire.

What went wrong with the setup in the garage fire at this point no one can say for certain, I think to much blame is being placed on the UMC.
 

widodh

Model S 85 and 100D
Jan 23, 2011
6,853
2,773
Venlo, NL
I tend to agree. I've always viewed the UMC as a way to plug-in when you are on the road and need the flexibility to hit a variety of outlets in the absence of a supercharger. I've never viewed the UMC as a means by which to charge my car in my own garage. For that I purchased the HPWC. I can't imagine anyone charging with just a single UMC, removing it from the receptacle each day when they leave. That is a lot of wear/tear on the receptacle.
Well, a lot of people out there only use their UMC and unplug it every time they leave with their S.

The UMC is easier to install than the HPWC. Besides the HPWC 2x's cost, there is also the extra cost of installing a disconnect switch which is required for the HPWC due to it being hard wired. For someone with an existing 240v outlet in the garage, the UMC makes perfect sense, provided he/she doesn't plug/unplug excessively and both wiring and outlet are up to par.

For my own installation I used a Hubbell commercial grade receptacle HUBBELL HBL9450A AC Receptacle NEMA 14-50 Female Black 125/250 Volt 50 Amp - Our Item #: 8694, Category: NEMA 4-Wire Receptacles : StayOnline
easily 4 times the cost of the receptacles the big box stores sell. I looked at both, the Hubbell is constructed better. I also used 6 gauge wire and an over-sized outlet box so the wires wouldn't have to be crammed in. I did this so I wouldn't worry about marginal parts being the reason for a fire.

What went wrong with the setup in the garage fire at this point no one can say for certain, I think to much blame is being placed on the UMC.
Again, what I'm trying to say that if the mass starts to buy EVs this will go wrong.

If you for example not fully insert the Nema 14-50 into the socket it will still charge, but it's very dangerous due to the reduced contact surface which will generate heat.

When using a HPWC it won't charge if the connector isn't fully inserted into the socket, so there is no way you can do that wrong.

That's the danger with the UMC. So many places where the user can make a mistake and potentially cause a fire.

And when you buy a $100k Tesla you shouldn't be saving on the charging installation. Safety goes first.
 
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CalDreamin

Member
Jun 12, 2013
439
13
Bay Area
I paid a licensed electrician $300 to install a HPWC in my garage, about the same as a NEMA 14-50 install would have cost. I wanted to keep the UMC in the car so it would be there when needed. I got twinchargers anyway to future proof for high amp charging on the road. While my HPWC is on a 100A circuit, only once in >12K miles of use have I charged with my HPWC at more than 40A. That happened when I'd already put 160 miles on the car in the morning and wanted to travel across the SF Bay to see the Model X in at the new Palo Alto store. So I could have saved $550 if I'd gotten another UMC instead of a HPWC. After reading stories about UMC plugs melting, I was glad I got a hardwired HPWC, which doesn't even get warm when charging at 40A.
 

CalDreamin

Member
Jun 12, 2013
439
13
Bay Area
Reading this thread has started me to think about a HPWC. Any recs. I'm looking at the Bosch.

I recommend the Tesla HPWC. Bosch EVSEs max out at 30A. If your MS has a single charger the HPWC can charge at up to 40A. If your MS has twinchargers the HPWC can charge up to 80A.
 

FlasherZ

Sig Model S + Sig Model X + Model 3 Resv
Jun 21, 2012
7,024
1,013
I need to add that I did read on this forum that the 14-50 outlet was not engineered to have the cables pugged and unplugged (a warning from an electrician) on a daily basis.

Depends on the model. There are ones used in RV parks that do expect many, many cycles.
 

RainmakerJL

Member
Oct 26, 2013
179
0
Westchester NY
Confused by all this. I had an electrician install an HPWC in my garage and I have the twin chargers in my car. It's set to a 100amp breaker.

I felt the hose today after my first charge and it was warm....

What is the harm in charging at 80amps at my house?

Can it not handle the charging?
 

gene

Supporting Member
Feb 11, 2013
2,229
11,823
Santa Barbara, CA
The average person drives less than 100 miles. On the tough screen you can set the amperage draw on the car for something lower, like 28 amps (which is where I set mine) which will easily charge you fully overnight and be a very light load for your Nema 14-50 setup. The car remembers your location for every future time you plug in, you need set it only once. A properly installed and wired 14-50 is safe at 40 amps, at 25 to 30 amp draw it is hugely safe.
 

jerry33

(S85-3/2/13 traded in) X LR: F2611##-3/27/20
Mar 8, 2012
19,631
22,276
Texas
I can't imagine anyone charging with just a single UMC, removing it from the receptacle each day when they leave. That is a lot of wear/tear on the receptacle.

It would be a lot of wear, but I suspect most folks are like me and never remove it from the receptacle except on trips or when taking it to the SC for inspection. Totally that's just a few times a year.

- - - Updated - - -

Confused by all this. I had an electrician install an HPWC in my garage and I have the twin chargers in my car. It's set to a 100amp breaker.

I felt the hose today after my first charge and it was warm....

What is the harm in charging at 80amps at my house?

Can it not handle the charging?

Warm is fine. Very hot is not.

There's no harm in charging at 80 amps, however it's thought that the charging and pack balancing are more efficient at lower amps. Lower amps are also easier on the infrastructure that's on the power company's side of the metre.
 

RainmakerJL

Member
Oct 26, 2013
179
0
Westchester NY
It would be a lot of wear, but I suspect most folks are like me and never remove it from the receptacle except on trips or when taking it to the SC for inspection. Totally that's just a few times a year.

- - - Updated - - -



Warm is fine. Very hot is not.

There's no harm in charging at 80 amps, however it's thought that the charging and pack balancing are more efficient at lower amps. Lower amps are also easier on the infrastructure that's on the power company's side of the metre.

Okay. I just got mine today so want to be careful. I cut the charge rate to 40amps. Quite frankly i do not care about my power company. They rake us over the coals and dont even have off peak rates....
 

cwerdna

Active Member
Jul 11, 2012
3,442
2,292
SF Bay Area, CA
I've looked at it and used it on occasion. My engineering analysis: a cheap piece of crap that I wouldn't trust behind my back for a second. Stays in the trunk.

Inside a building use ONLY wall mounted EVSEs: Aeroviron, Schneider, Clipper Creek, Tesla's HPWC, etc properly connected. Or mount them on an outdoor post or wall. My 14-50 box will be on a post outside, just like in an RV Park.

--
The UMC does have issues. Several melt downs have occurred. Mine may have wiring issues ( it is positional). The more important problem with daily use is the most NEMA 14-50 receptacles are not made to tolerate 10,000 in and out pluggings.
I haven't had time to read this entire thread yet, but cheaper alternatives to HWPC, esp. if your car doesn't have twin (on-board) chargers, is to go w/with properly installed by an electrician hardwired (or pluggable, but staying plugged) EVSE. Electric Vehicle Charging Stations| EV Charging - Clipper Creek has a good rep and they recently announced a 30 amp @ 240 volt HCS-40 for $590. You'd need to use your J1772 adapter though.

Leviton has a 40 amp EVSE that is intended for the Rav4 EV (aka "poor man's Tesla", has a 10 kW OBC, like the Model S). See http://toyota.leviton.com/ and http://www.leviton.com/OA_HTML/ProductDetail.jsp?partnumber=EVB40-PST&section=37741&minisite=10251. IIRC, I've heard mixed reports about that unit.
 
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bareyb

Active Member
Sep 2, 2013
1,137
46
Silicon Valley, CA
Why would anyone unplug their UMC and bring it with them every day? I suppose there are those that commute hundreds of miles a day, but I can't imagine that's very common. If I needed to (for some reason) bring a UMC with me every day I'd spend the $650.00 and buy another one to keep in the car. No way I'd drop $1200.00 for an HPWC when a UMC can top off my car in about 2 hours for half the price. The UMC was designed to be used every day and it's more than enough for most people's overnight charging needs. For my purposes, an HPWC would be a waste of money and it would have to be removed when I sell the house. With a 220 Volt outlet, future EV Owners can just plug-in.
 
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JST

Active Member
May 23, 2013
1,560
222
Why would anyone unplug their UMC and bring it with them every day? I plugged my UMC into my 14-50 Outlet the day I brought my car home and I've never had the need to unplug it once. I suppose there are those that commute 260 mies a day, but I can't imagine that's very common. If I needed to (for some reason) bring a UMC with me every day I'd spend the $650.00 and buy another one to keep in the car.

I drive at most, 50 miles a day (in Tesla Miles) No way I'd drop $1200.00 for an HPWC when a UMC can charge it in 2 hours. If you are concerned about safety you can simply charge at a lower rate (I use 30 Amps).

I have a 14-50 installed at home and a 14-50 in the garage at work. At home the outlet is outside (no garage) and at work it's unsecured.

I've been plugging in my UMC at home and at work every day. What else can I do? I don't want to leave my UMC plugged in and exposed to the weather at home. I don't want to leave it at the office and potentially have it stolen.

I don't need to charge both places, since my commute is maybe 20 miles roundtrip, but I also figure as long as the car is sitting in one place for 8-10 hours it might as well be plugged in.

Short of dropping $2400 on two HPWCs, what should I do?
 

bareyb

Active Member
Sep 2, 2013
1,137
46
Silicon Valley, CA
I have a 14-50 installed at home and a 14-50 in the garage at work. At home the outlet is outside (no garage) and at work it's unsecured.

I've been plugging in my UMC at home and at work every day. What else can I do? I don't want to leave my UMC plugged in and exposed to the weather at home. I don't want to leave it at the office and potentially have it stolen.

I don't need to charge both places, since my commute is maybe 20 miles roundtrip, but I also figure as long as the car is sitting in one place for 8-10 hours it might as well be plugged in.

Short of dropping $2400 on two HPWCs, what should I do?

Well that sucks… In your situation I'd probably do exactly what you're doing. If you had a garage I'd recommend getting a second UMC for Work. :(
 

MikeC

Supporting Member
Jul 9, 2012
2,859
5,134
Los Angeles
I believe this is an internal memo from TM:

-------------------

If asked about the garage fire in Irvine, California…

· Yes, we are aware of the garage fire in Irvine, California last month. We conducted a thorough inspection of the site, the car and the logs and can say with absolute certainty that the fire was not caused by Model S, the battery or the charging electronics.

· The fire was at the wall socket where the Model S was plugged in, but the vehicle itself was not part of the fire. And the damage to the cable was on the wall side; the cable on the vehicle side was fine.

· The inspection of the car and the battery make clear that neither were the source of the garage fire. In fact, they were both functioning normally after the incident.

· A review of the car’s logs showed that the battery had been charging normally and there were no fluctuations in temperature or malfunctions within the battery or the charge electronics.

· The fire department’s report emphasizes that the cause of the fire was unclear to them, and we know for certain that the fire was not caused by Model S, the battery or the charging electronics.

· The journalists and editors had all of this information, but made the disappointing choice to publish a deeply misleading article in spite of that. It seems like their objective was to find some way to put the words “fire” and “Tesla” into the same headline regardless of the facts.

· This garage fire is totally unrelated to and unlike the accidents that you may have read or heard about in the news in the past few months. Again, it’s important to remember that the fire here was at the wall socket, not at the car, the battery or the charging electronics.

· If a customer has any concern about their charging situation, we will be happy to come to their location to inspect the outlet and the mobile connector, or the high power connector, if applicable, for free.

o If any issues are found, we will either repair them immediately or recommend next steps to the customer.

· If a customer contacts us with concerns about adaptor or receptacle heating, let them know that they can manually reduce their charging current through the car’s center display. Doing this will naturally reduce any heating in the wires and connectors in the home and leading up to the vehicle.
 

brianman

Burrito Founder
Nov 10, 2011
17,526
2,994
The change in 5.8.4 seems related. Not an admission of fault but a good step in the direction of ongoing improvements where possible.
 

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