ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals
ECN Shout Chat
Shout Box
Recent Posts
by Rabbit. 03/20/18 08:23 PM
Recall notice: Southwire wi-fi wall switches
by sparkyinak. 03/15/18 06:03 PM
Goodman Manufacturing Recalls Modular Blowers
by Admin. 03/13/18 10:40 PM
MAAX Spas Recalls Hot Tubs and Swim Spas
by Admin. 03/13/18 10:29 PM
New in the Gallery:
Housebilding DIY wiring
SE cable question
Who's Online Now
0 registered members (), 8 guests, and 7 spiders.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate Thread
Interesting..... #212509
01/14/14 09:41 PM
01/14/14 09:41 PM
HotLine1  Offline
Joined: Apr 2002
Posts: 6,935
Brick, NJ USA
From the AOL news flashes....

Tesla Motor Company, maker of the Model S electric car, is recalling 29,222 wall charger adapters following reports of overheating in owners' garages.

The National Highway Traffic Safety Administration (NHTSA) announced the recall Tuesday morning. Tesla said the problem lies in the Universal Mobile Connector (UMC) adapters, which can lead to the adapter, cord or wall outlet overheating during charging. The danger was discovered when a garage caught fire in California in November. It has since resulted at least five incidents that were reported to NHTSA's complaint database.

"These are very rare events, but occasionally the wiring isn't done right," Tesla CEO Elon Musk said, according to Bloomberg. "We want people to have absolute comfort, so we're going to be providing them with an upgraded adapter."

The new adapter will include a thermal fuse that will shut off charging if overheating is detected, Musk said. Tesla sent a software update to its customers to deal with the overheating issue back in December, which was designed to trigger a 25 percent reduction in charge current when it sensed a potential overheating.

Tesla said about 2.9 percent of Model S buyers have returned their UMC adapters because of defects

Work Gear for Electricians and the Trades
Re: Interesting..... [Re: HotLine1] #212510
01/14/14 11:32 PM
01/14/14 11:32 PM
shortcircuit  Offline
Joined: Jun 2004
Posts: 608
I saw a charger that had a 100amp circuit going to it for a Tesla. Are these the ones that caught fire?

Re: Interesting..... [Re: HotLine1] #212511
01/14/14 11:48 PM
01/14/14 11:48 PM
Tesla  Offline
Joined: Jun 2004
Posts: 1,273
Sacramento, CA
Tesla uses a non-industry standard connection.

The fundamental problem: Lithium-ion batteries are prone to run-away charging and discharging dynamics.

This is the source of the chronic fires:

Boeing's 787

Tesla's roadster battery array

Tesla's charging system


This tick gets even more pronounced as the batteries get better.

The current solution is to actively sense the temperature -- and to throttle the current via semi-conductor means.

(Probably an IGBT)

These switches are changing everything on the load-side.

Eventually, three-phase motors will be commonly powered by single-phase circuits. IGBTs will permit 3-phase synthesis. This has already been proto-typed in hermetic refrigeration compressors.

The ability to throttle such compressors up and down increases their efficiency -- and makes them last three times as long. (It's virtually a solid state solution.)

Re: Interesting..... [Re: HotLine1] #212512
01/15/14 01:14 AM
01/15/14 01:14 AM
gfretwell  Online Content

Joined: Jul 2004
Posts: 9,186
I like manual reset thermal switches for stuff like this. I was collecting them for years at IBM. We used to have engineering changes where they got swapped for a different temperature quite often and I put the old one in my pocket instead of throwing it away.
I had one save me from a serious problem on my spa. I had a problem where a heater ran away and my thermal tripped it out at ~122f. I changed that to 110f because I decided that was even too hot.

If I had something like this I would have a thermal right on the charger.

Greg Fretwell
Re: Interesting..... [Re: HotLine1] #212513
01/15/14 11:28 AM
01/15/14 11:28 AM
jdevlin  Offline
Joined: Aug 2002
Posts: 402
welland ontario canada
The article I read about it said they were making a software upgrade to fix it and the new units would have a thermal fuse in the NEMA 14-50 plug.

Re: Interesting..... [Re: HotLine1] #212514
01/15/14 02:49 PM
01/15/14 02:49 PM
gfretwell  Online Content

Joined: Jul 2004
Posts: 9,186
That might be OK for an overload but the charger could burn up without actually overloading the circuit.

Greg Fretwell


2017 Master Electrician Exam Preparation Combos
2017 NEC Electrician
Exam Prep Combos:
Master / Journeyman


Member Spotlight
Amish Country, PA
Posts: 46
Joined: March 2013
Show All Member Profiles 
Top Posters(30 Days)
Admin 5
Trumpy 5
Popular Topics(Views)
244,535 Are you busy
181,661 Re: Forum
171,707 Need opinion
Powered by UBB.threads™ PHP Forum Software 7.6.1
(Release build 20180101)
Page Time: 0.030s Queries: 15 (0.005s) Memory: 0.9778 MB (Peak: 1.1220 MB) Zlib enabled. Server Time: 2018-03-21 07:12:05 UTC