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Mobile charger will not work properly

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Hi to all
We got our S85 yesterday. Being an engineer, I put it on charge at 30A instead of 40A to test how things are functioning. We have 242V at the outlet with the car on charge. We had the electrician put in #4 wiring, 52 feet underground from the breaker box instead of #6 so the feed side is cool into the garage outlet. The 14-50 outlet was just detectably warm after an hour at the plug faceplate, but the Tesla wiring was markedly warm- this concerns me a bit as the difference going from 30A to 40A is about 65% more energy dissipation in the cable (ratio of 40^2 to 30^2). The plug at the car was a bit warm too. I am going to put a thermocouple on the different areas and monitor, and report later on.

I share your concern if it's more than just warm to the touch at 30A. "Detectably warm" is fine, if you can't touch it, it's a bad thing. I use an infrared thermometer to read mine. I've had my UMC replaced once because of a melting problem at the adapter and my HPWC cable replaced because of a loose connection at the car.

The #4 is a bit overkill IMO, considering that even #8 is sufficient if THHN in conduit. At least you're erring on the safe side.
 
Hi to all
We got our S85 yesterday. Being an engineer, I put it on charge at 30A instead of 40A to test how things are functioning. We have 242V at the outlet with the car on charge. We had the electrician put in #4 wiring, 52 feet underground from the breaker box instead of #6 so the feed side is cool into the garage outlet. The 14-50 outlet was just detectably warm after an hour at the plug faceplate, but the Tesla wiring was markedly warm- this concerns me a bit as the difference going from 30A to 40A is about 65% more energy dissipation in the cable (ratio of 40^2 to 30^2). The plug at the car was a bit warm too. I am going to put a thermocouple on the different areas and monitor, and report later on.

I have similar concern. After using my UMC for a year at 40 Amp. I notice the Tesla 14-50 adapter plug felt very warm. When I measured it with an IR thermometer and it was 68 °C (43 °C above ambient), ouch! I immediately throttled back charging to 30 Amps. while I figured what to do. After I replaced my 14-50 outlet the Tesla 14-50 adapter ran 50 °C (28 °C above ambient), while running cooler this still seem very hot to me. After reading so many issues on this forum I decided to modify one of my two UMCs by cutting off Tesla’s adapter and replacing it with Hubbell HBL9451C 14-50 plug and a 9.09K ohm signaling resistor on the fourth control pin. (Note, I am an electrical engineer with 30 years design experience.) I was very happy with the results. The new plus plug is running 29 °C (7 °C above ambient). A better (apples-to-apples) comparison would be to compare the cord temperature where it exits the plug. It dropped from 46 °C (24 °C above ambient) with the Tesla adapter to 38 °C (16 °C above ambient) with the Hubbell HBL9451C 14-50 plug. Note, it has been a month since I received my Tesla recall notice (March 11) that my new adapter with arrive in two weeks.
 
This must be contagious! Yesterday I had the exact same problem. BTW, great youtube video, it showed exactly what I was experiencing. I had a spare charging cable and set that up and it worked. Checked 30 minutes later and car said fully charged, but it wasn't. Got service on the phone. They had me re-boot the computer and reset the charger. Then it was fine. But this is now on my radar, too.
 
Charger died last week. I use one mobile charger everyday through a NEMA 14-50 and keep a spare mobile charger in the trunk for traveling. Main one failed, switched to spare cord and in plugging in the spare my iphone falls off a shelf next to the wall plug and shatters...

I wonder if Tesla should advise people to NOT use the mobile charger as an everyday one? They do not seem to be reliable enough. This was my third mobile charger since December 2013. Must cost them a fortune to FedEx replacements, deal with the melting adapters and other problems. Would be cheaper to cut the price of the HPWC to $650, perhaps? Only issue I have had with the vehicle are all with the mobile charge cord.
 
I wonder if Tesla should advise people to NOT use the mobile charger as an everyday one? They do not seem to be reliable enough. This was my third mobile charger since December 2013. Must cost them a fortune to FedEx replacements, deal with the melting adapters and other problems. Would be cheaper to cut the price of the HPWC to $650, perhaps? Only issue I have had with the vehicle are all with the mobile charge cord.

In some territories they are doing exactly that - not supplying the UMC and suggesting other sources of EVSE. In the UK, they are instead supplying a type2 cable for use at public charge points, and don't need to supply anything for home charging as there's a government scheme supplying heavily-subsidised permanently installed EVSE to homes. In Hong Kong they are apparently supplying some kind of wall mount EVSE for customers to have installed (HPWC equivalent; not clear if it's Tesla's own or third-party off-the-shelf).
 
I was ask by others in the forum how I installed a Hubbell HBL9451C Plug onto my UMC.

Disclaimer:
I hesitate to give these instructions because they are for someone skilled in electrical rework. Skills needed to install a Hubbell HBL9451C Plug on to the Tesla Model S UMC:

  1. Stripping wire,
  2. Soldering (tinning) two stranded 12 GA wires together,
  3. Soldiering (attaching) 18 or 20 GA hookup wire to stranded 12 GA wire,
  4. Soldering (attaching) a resistor to 18 or 20 GA hookup wire,
  5. Putting two layers of heat shrink tubing around the exposed resistor body and its leads which are connected to the 18 or 20 GA hookup wire and
  6. Have done similar things like this before.
If you don’t have these skills don’t start. Find someone that does.
Also, I am sure Tesla would not be please if something went wrong with the UMC after you modified it and you brought it back for replacement. In my case, I have charged over 31,000 miles using my UMC and other than the plug getting hot, it has been working fine. So, I took a chance.
Material needed:

  1. Hubbell HBL9451C Plug
    http://www.amazon.com/gp/product/B000TKF84E/ref=oh_details_o00_s00_i00?ie=UTF8&psc=1
  2. Resistor, 9.1K or 9.09K, 1 Watt, through hole, metal file, 1 or 5%
    http://www.digikey.com/product-search/en?vendor=0&keywords=PPC9.1KW-1CT-ND&stock=1
  3. 3” 18 or 20 GA hook up wire
  4. Heat shrink tubing (enough to put two layers around the resistor, its leads and soldered wire connection. I like:
    Amazon.com: Ancor 301503 Marine Grade Electrical Adhesive Lined Heat Shrink Tubing Kit (3/16 to 3/4-Inch Diameter, 3-Inches Long, Black, 8-Pack): Sports Outdoors
  5. Small tie wraps.
Simplified instruction: 1) Install the 9.1K resistor between the stripped green/yellow and violet signal wire. 2) Install the Hubbell HBL945C Plug.
More detail Instructions:

  1. Cut off the Tesla universal adapter.
  2. Strip the cable per the instructions that come with the Hubbell HBL9451C Plug. Note, the two red wire leads will be twisted together and the two black wire leads will be twisted together.
  3. Solder (tin) the twisted red and black wire together.
  4. Strip around 1.25 to 1.5” off the 3” hook up wire and wrap it around the green/yellow wire by aligning the edges of both wire insulation together and twisting.
  5. Solder the two wires together.
  6. Strip about 0.5” off the violet and hookup wire so that they can be wrapped around and attached to the resistor leads.
  7. Solder one resistor lead to violet wire.
  8. Install heat shrink tubing around violet wire and resistor lead.
  9. Cut more heat shrink tubing for the hookup wire and 2[SUP]nd[/SUP] resistor lead. Note, you want two layers of heat shrink tubing protecting the resistor body and its leads. Also, the tubing needs to be far enough away from the lead when you are soldering so that the heat from soldering does not make it shrink. If it shrinks you won’t be able slide it over the resistor body and/or resistor lead.
  10. Solder 2[SUP]nd[/SUP] resistor lead.
  11. Move heat shrink tubing in place and shrink.
  12. Put heat shrink over the end of the blue wire and shrink. Note, the blue wire is NOT stripped. This is a precaution to make sure it does not accidently connect to AC power or ground.
  13. Gently bend the resistor and its leads so that it is next to the green/yellow insolation between the stripped current carrying wire and the cable black jacket. Put a tie or two to hold it in place. Note, there is plenty of room in the Hubbell plug to accommodate the now insulated resistor and its connections without being pinched.
  14. Attached Hubbell HBL9451C Plug per instructions that come with it.
  15. Done.