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J1772 EVSE or direct UMC connect to 240v outlet?

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On Saturday I'm taking possession of my new S 85D, upgrading from a Volt (yeah!). I have this Seiemens 30A EVSE level 2 charger (Amazon.com: Siemens VC30BLKB 30-Amp Bottom Fed VersiCharge Electric Vehicle Charger: Home Improvement) in my garage connected to a 240V outlet wired to a 40A breaker. So I have two options for charging my Tesla: connect to the EVSE via the J1772 adaptor or connect directly to the 240v outlet. Because I only have a 40A breaker I cannot charge more than 30A so I am not sure it matters whether I use the EVSE or not?

Thoughts?

tha k you!
 
Congrats! 30A should be fast enough for most overnight charging. If just use your EVSE with the adapter. You could also use your Tesla UMC but would likely need to buy an adapter from Tesla. What kind of plug is it?
 
It's my understanding that the car delivers with "Mobile connector with 110 volt, 240 volt, and J1772 adapters", quoting from the Model S page on teslamotors.com. As I read this I should be able to choose which I use without needing to buy anything further. Right?
 
Tesla bundles the J1772, 110V (NEMA 5-15) and 240V (NEMA 14-50) adapters with the car.

If this manual is applicable to your EVSE:

http://w3.usa.siemens.com/us/internet-dms/btlv/residential/residential/docs_Home/SIE_IM_VersiCharge.pdf

Then, you may have a NEMA 6-50 outlet which means that, if you want to use the Tesla UMC directly, then, you may be out of luck as Tesla discontinued their 6-50 adapter recently. Other adapters are available here:

Tesla Gear Shop Charging and Adapters

So, just using the EVSE with the Tesla J1772 adapter is the easy answer.
 
This has been very helpful. Thanks everyone! I see it is a 6-50 but I had assumed it was a 14-50 ... fortunately for me I have the EVSE a with J1772 so I have a solution until I decide to upgrade my wiring.

BTW the charger is spec'd as 30A with up to 7.2kW output. I assume for the Model S I should get all 30A of charging power for approximately 22 miles of battery storage per hour? I know there are many factors but I'm basing this off the simple calculator on the Model S website.

Thanks again
 
This has been very helpful. Thanks everyone! I see it is a 6-50 but I had assumed it was a 14-50 ... fortunately for me I have the EVSE a with J1772 so I have a solution until I decide to upgrade my wiring.

BTW the charger is spec'd as 30A with up to 7.2kW output. I assume for the Model S I should get all 30A of charging power for approximately 22 miles of battery storage per hour? I know there are many factors but I'm basing this off the simple calculator on the Model S website.

Thanks again

If the wire in the wall is #8 in conduit or #6 romex, you can probably upgrade the breaker to 50 Amps. The 6-50 does not have a neutral, but the HPWC does not need one. I would seriously consider buying an HPWC for $750, putting it where the 6-50 is, and leave the UMC in the car for when you need it unexpectedly.
 
Stick with your 30a EVSE. Lesson learned. I have a 30a EVSE for my BMW I3. When I ordered my P85D I spent thousands upgrading the power to my garage to accommodate the Tesla HPWC. Then when it arrived the Tesla shop told me to dial the P85D charge current down from 80A to 20-to-30A for battery longevity. So in the end thousands wasted... Now I spend most nights between 20 and 30 amps. FWIW I didn't want to believe the service advisor so I called California and asked them if this was correct and they verified that guidance.
 
We had a Nissan Leaf for two years before our first Tesla became a stable-mate. Since we had both cars and a single device, I stuck with my setup quite similar to yours. Eventually I did upgrade to a 40A Leviton unit since it worked with both the Leaf and the Tesla, but yes I bought myself a spare J1772 adapter for home (that way the Tesla's adapter stayed in the trunk in case I needed it "out in the wild")

That is interesting advice given to the user who said they were told to not charge at 80A all the time. My home is a 100A service so doing an 80A setup (HWPC) isn't even an option for me, even though my car has dual chargers (inventory vehicle, had that feature, not one I'd otherwise have purchased it with).

Anyhow, I would agree the 40 vs 30 amp won't make a difference most of the time. If you do upgrade but want to keep the ability to charge J1772 vehicles, my suggested upgrade for 40A is still something that you'd have to make sure the wire/breaker can be upgraded to permit... and this is the unit I'm using now:
Amazon.com: Leviton EVB40-PST Evr-Green 400 EV Charger, 40-Amp, Surface Mount, 25-Foot Cord, Requires 50Amp Circuit: Home Improvement
 
Most people use home charging for overnight... 30A is usually plenty to get a full charge in that many hours.
The mobile connector doesn't have a stellar reputation for reliability, so it might be better to use your existing EVSE and keep the mobile connector in little used condition as a backup when you are traveling on the road somewhere.
 
Stick with your 30a EVSE. Lesson learned. I have a 30a EVSE for my BMW I3. When I ordered my P85D I spent thousands upgrading the power to my garage to accommodate the Tesla HPWC. Then when it arrived the Tesla shop told me to dial the P85D charge current down from 80A to 20-to-30A for battery longevity. So in the end thousands wasted... Now I spend most nights between 20 and 30 amps. FWIW I didn't want to believe the service advisor so I called California and asked them if this was correct and they verified that guidance.

Somebody gave you bad information. I've never heard that charging about 20-30A is harmful. If you get a full charge in the morning at that rate I guess it couldn't hurt but if you need a faster charge go ahead.
 
Keep the already-installed 30A EVSE.
Affix the J1772 to TSL02 adapter to the EVSE
Get one of the charge door popper buttons someone was selling, and put it on the connector
Keep your UMC in the car.

The only reason I wouldn't do the above solution is if you think you really would need 40A charging.
 
Somebody gave you bad information. I've never heard that charging about 20-30A is harmful. If you get a full charge in the morning at that rate I guess it couldn't hurt but if you need a faster charge go ahead.

That is the opposite of what I said.

After spending thousands for dual chargers and getting an extra 100A circuit wired to my garage, I learned that Tesla recommends charging at much less for the purposes of battery longevity.

They recommend dialing down the charge amperage from 80 to the minimum amperage necessary to recharge by morning. Actually told me to look at the vehicle display for estimated number of hours to charge and dial the charge amps down until the number of hours to charge = number of hours until I will drive the car again. It all makes perfect sense and I'm not complaining, I actually appreciate the recommendation from Tesla, and wish the car would automatically figure this out for you.

But for the purpose of this thread, I was advising Robert against spending money to "throw out" a perfectly good 30A EVSE because in the end that would be all I needed to recharge my power hogging P85D. That is, unless Robert drives substantial miles per day or doesn't have enough overnight hours to recharge.

Robert take the average number of miles per day you drive and divide by 17. That roughly approximates the number of hours it will take to charge using your existing EVSE (Although YMMV depending upon driving style). Then ask yourself if you will typically have that many overnight hours to charge.

For example if you typically drive 100 miles per day, it would take just under 6 hours to charge. Are you normally home from 11pm to 5am?
 
On Saturday I'm taking possession of my new S 85D, upgrading from a Volt (yeah!). I have this Seiemens 30A EVSE level 2 charger (Amazon.com: Siemens VC30BLKB 30-Amp Bottom Fed VersiCharge Electric Vehicle Charger: Home Improvement) in my garage connected to a 240V outlet wired to a 40A breaker. So I have two options for charging my Tesla: connect to the EVSE via the J1772 adaptor or connect directly to the 240v outlet. Because I only have a 40A breaker I cannot charge more than 30A so I am not sure it matters whether I use the EVSE or not?

Thoughts?

tha k you!

Will you have two plug-in cars? If so, keep the 30 Amp Siemens for your other car, and add a 14-50 or HPWC for your 85D.

Does your 85D have dual chargers? If not, you can' t use more than 40 Amps, which should be plenty for overnight charging. I like the more robust hard wired HPWC anyway, especially at the new price of only $750, and keep the UMC in the trunk. Also, your 6-50 wiring might be ok as is for a 50 Amp breaker and the HPWC, but a 14-50 requires an extra wire for the neutral. The HPWC can be configured for many breaker sizes from 20 A to 100 A.

If you are going to stick with one plug-in car, then using your 30 Amp Siemens with the J1772 adapter is the most pratical solution, and you can keep the UMC in the trunk. The key fob can open the charge point door (if I remember correctly), or you can buy an inexpensive aftermarket fob from lolachampcar here on the forum and attach it to your Siemens unit.

GSP
 
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If you have #8 wire, on a 40A circuit breaker, then you can draw up to 32A.
Your EVSE is probably limited to 30A because of the J-1772 wire used (10AWG only good for 30A)

Although if you have #8 wire in conduit, you may legally replace the 40A circuit breaker with a 50A circuit breaker, and use 40A charging current. You may not do this if NM-B (Romex) cable was used.

- - - Updated - - -

For what it's worth, my HPWC always charges at 80A on a daily basis, and range charges still hit 264/265 miles after nearly 50,000 miles (although 32k on this battery, due to the early contactor failure).