HPWC Charging Limited to 79A

[wk057]

I was wondering if the line voltage was high (250-270) the chargers might throttle back a bit to keep things from exceeding 20kw. I have no ability to test here, because I rarely see 250.

Gen1 throttles at 10.5 kW last I checked, gen2 works up to 300V no throttle.

 

[brantse]

My house is always supplied "hot" (252-257v). I often see 10.1 or 10.2 kW.

 

[Andyw2100]

http://www.teslamotorsclub.com/show...ter-charging-with-your-single-charger-Model-S

Before anyone checks the link above, and thinks "What a great idea!", this is what FlasherZ, one of the most knowledgeable and well-respected posters here with respect to all things having to do with electrical power, wiring, etc. had to say about it:

This is a bad idea - even though the internals of the chargers may be rated higher, the warranty may not cover charging in this manner.

Mods: I'm recommending a thread subject change - lots of people are going to read this and wonder if they can hack something together. This is dangerous. Add "[crazy hack]" or something to the front please?

 

[pchilds]

Before anyone checks the link above, and thinks "What a great idea!", this is what FlasherZ, one of the most knowledgeable and well-respected posters here with respect to all things having to do with electrical power, wiring, etc. had to say about it:

It's all in the link. Do you think people can't read? If they can't read, repeating the warnings won't do any good. I have been charging at 277 vac for 3 years, no warranty or safety issues, if done properly.

 

[FlasherZ]

It's all in the link. Do you think people can't read? If they can't read, repeating the warnings won't do any good. I have been charging at 277 vac for 3 years, no warranty or safety issues, if done properly.

While you may not have had an issue, if someone else's charger were to fail while using such a device and Tesla were to look at the logs, the person you "helped" may not receive warranty coverage for his error. It's important to let people know that.

I can't change your mind, obviously - but I can continue to tell people that it is simply a bad idea, period. Good luck with your car, but please don't tell others to do something that may affect their warranty or safety.

 

[Andyw2100]

It's all in the link. Do you think people can't read? If they can't read, repeating the warnings won't do any good.

I think they can read, but I also think sometimes people skim things and don't read things thoroughly.

I also think people don't appreciate having their time wasted.

I know if I saw a link to a random thread that sounded interesting and someone then showed excerpts from that thread from a highly respected poster saying essentially "this thread is dangerous, and probably a waste of your time" I would appreciate the heads-up, and the fact that the second poster was saving me time, and looking out for me.

That's what I was doing for the readers of this thread by showing them what FlasherZ had to say.

People are, of course, still free to read your thread if they so desire.

 

[pchilds]

While you may not have had an issue, if someone else's charger were to fail while using such a device and Tesla were to look at the logs, the person you "helped" may not receive warranty coverage for his error. It's important to let people know that.

I can't change your mind, obviously - but I can continue to tell people that it is simply a bad idea, period. Good luck with your car, but please don't tell others to do something that may affect their warranty or safety.

The same chargers are run at 277 vac in Superchargers, they are not going to fail from 277 vac. To deny a warranty claim, Tesla would have to prove that the 277 vac made the charger fail and if they run the same chargers in their Superchargers, that doesn't fly.

You say safety? Are you trying to say the charger could catch on fire? How many Superchargers have caught on fire? The chargers are designed for 277+ enough scaremongering.

 

[FlasherZ]

The same chargers are run at 277 vac in Superchargers, they are not going to fail from 277 vac. To deny a warranty claim, Tesla would have to prove that the 277 vac made the charger fail and if they run the same chargers in their Superchargers, that doesn't fly.

You say safety? Are you trying to say the charger could catch on fire? How many Superchargers have caught on fire? The chargers are designed for 277+ enough scaremongering.

No, they would not have to prove that the 277 VAC made the charger fail. In the case where a supercharger is used, 277 VAC doesn't get fed to the car -- DC voltage does. All Tesla would have to do is demonstrate that you were using a voltage out of spec, as J1772 level 2 charging specifies 208/240V split-phase. It doesn't matter whether the same charger can be repurposed in the supercharger cabinet or not.

From J1772-2010 spec:

Tesla's AC charging is based upon the J1772 spec (with a different form-factor connector).

And yes, safety -- autotransformers have some peculiar characteristics that create safety concerns. I mention them in the other thread.

It's not scaremongering... it's the truth. It's time for you to stop spreading misinformation.

 

[pchilds]

It's not scaremongering... it's the truth. It's time for you to stop spreading misinformation.

#6 THHN wire is good for 52 amps continuous with a 70 amp breaker. I am not using a UMC, the contactor in my EVSE is rated for the current. If you don't know that, when you are boosting the voltage, the input of the transformer will have more current than the output, don't do it. I am not spreading misinformation, just sharing what works.

 

[mknox]

The amperage is a rounding error with the gen2 chargers. Not a huge deal. It's adding up six sub modules worth of current and losing precision along the way to the UI.

I see the same thing on my Feb 2013 build car with the dual charger option... but only sometimes. I installed a pair of 80 amp J1772 stations at my office, but can only get 79 amps max at them. I can't even dial it up beyond 79 amps so I suspect that is the pilot signal the car is seeing. Oddly other Tesla cars can get the full 80 amps. A Tesla rep stopped by with a brand new P90D and he was able to get the full 80. We chatted about this for a bit. (I'm honestly not worried about 1 amp).

 

[AmpedRealtor]

I see the same thing on my Feb 2013 build car with the dual charger option... but only sometimes. I installed a pair of 80 amp J1772 stations at my office, but can only get 79 amps max at them. I can't even dial it up beyond 79 amps so I suspect that is the pilot signal the car is seeing. Oddly other Tesla cars can get the full 80 amps. A Tesla rep stopped by with a brand new P90D and he was able to get the full 80. We chatted about this for a bit. (I'm honestly not worried about 1 amp).

I also have a 2013 build and my screen has always said 79A even though it's receiving an 80A pilot signal. I asked service about it, they said it's a rounding error. I asked this question before the D and Autopilot.

 

[mknox]

I also have a 2013 build and my screen has always said 79A even though it's receiving an 80A pilot signal. I asked service about it, they said it's a rounding error. I asked this question before the D and Autopilot.

Oddly, I do get an 80 amp pilot signal (and 80 amps delivered) when connected to a HPWC. It was only on my 80 amp J1772 stations that I saw 79. The curiosity in my mind was around the fact that other Teslas saw 80 amps at those same J1772 stations.

 

[FlasherZ]

Oddly, I do get an 80 amp pilot signal (and 80 amps delivered) when connected to a HPWC. It was only on my 80 amp J1772 stations that I saw 79. The curiosity in my mind was around the fact that other Teslas saw 80 amps at those same J1772 stations.

My car very rarely shows 80A.

teslaRIMARY> db.tesla_aux.find({'chargeState.fast_charger_present':false,'chargeState.charger_actual_current':{$eq:79}}).count()
45989
teslaRIMARY> db.tesla_aux.find({'chargeState.fast_charger_present':false,'chargeState.charger_actual_current':{$eq:80}}).count()
29

Only 29 times have I ever seen 80A. Roughly 46,000 other times I've seen 79A.

Voltages when I've seen 80A:

{ "chargeState" : { "charger_voltage" : 204 } }
{ "chargeState" : { "charger_voltage" : 205 } }
{ "chargeState" : { "charger_voltage" : 246 } }
{ "chargeState" : { "charger_voltage" : 243 } }
{ "chargeState" : { "charger_voltage" : 242 } }
{ "chargeState" : { "charger_voltage" : 242 } }
{ "chargeState" : { "charger_voltage" : 243 } }
{ "chargeState" : { "charger_voltage" : 242 } }
{ "chargeState" : { "charger_voltage" : 243 } }
{ "chargeState" : { "charger_voltage" : 243 } }
{ "chargeState" : { "charger_voltage" : 242 } }
{ "chargeState" : { "charger_voltage" : 241 } }
{ "chargeState" : { "charger_voltage" : 242 } }
{ "chargeState" : { "charger_voltage" : 240 } }
{ "chargeState" : { "charger_voltage" : 242 } }
{ "chargeState" : { "charger_voltage" : 242 } }
{ "chargeState" : { "charger_voltage" : 241 } }
{ "chargeState" : { "charger_voltage" : 241 } }
{ "chargeState" : { "charger_voltage" : 241 } }
{ "chargeState" : { "charger_voltage" : 240 } }
{ "chargeState" : { "charger_voltage" : 239 } }
{ "chargeState" : { "charger_voltage" : 239 } }
{ "chargeState" : { "charger_voltage" : 239 } }
{ "chargeState" : { "charger_voltage" : 240 } }
{ "chargeState" : { "charger_voltage" : 239 } }
{ "chargeState" : { "charger_voltage" : 239 } }
{ "chargeState" : { "charger_voltage" : 239 } }
{ "chargeState" : { "charger_voltage" : 238 } }
{ "chargeState" : { "charger_voltage" : 238 } }

It appears that lower voltages permit 80A, the only outlier is 246V.

 

[mknox]

It appears that lower voltages permit 80A, the only outlier is 246V.

Hmmm. The 80 amp J1772 stations at my office were on a 208 volt circuit and I generally saw about 200 volts at the car. Only got a 79 amp pilot signal there. Other Teslas saw 80. I don't have 80 amps at home and can't recall what the voltage was at the HPWCs where I do see 80 in my car.

 

[Andyw2100]

The original issue as reported by breser, discussed in the first few posts in this thread, was eventually resolved via a software update. My car had always shown 79 amps as the pilot signal, even though 80 was available. Since the issue was resolved via the firmware update, my car has always shown 80 amps available.

I'm sure there are other issues involved here as well. I just wanted to point out that the original issue has been resolved.

 

[mknox]

The original issue as reported by breser, discussed in the first few posts in this thread, was eventually resolved via a software update. My car had always shown 79 amps as the pilot signal, even though 80 was available. Since the issue was resolved via the firmware update, my car has always shown 80 amps available.

Hmmm. I still see the 79 amp pilot signal and am on the most recent version of 7.1 (installed at the Service Center earlier this week).

 

[FlasherZ]

Hmmm. I still see the 79 amp pilot signal and am on the most recent version of 7.1 (installed at the Service Center earlier this week).

Mine shows an 80A pilot signal (charger_pilot_current = 80) but the car very, very rarely will bring the charging current (charger_actual_current) above 79.

 

[mknox]

Mine shows an 80A pilot signal (charger_pilot_current = 80) but the car very, very rarely will bring the charging current (charger_actual_current) above 79.

When I'm at my office's 80amp J1772 stations I see 79/79 amps and my car will not let me dial it up past 79. Other Model S's are getting 80/80 at the same station. I have been at 80 amp HPWCs and see 80/80 amps at those.

 

[Andyw2100]

Hmmm. I still see the 79 amp pilot signal and am on the most recent version of 7.1 (installed at the Service Center earlier this week).

Well, the issue as reported was affecting the Ds, and perhaps other newer cars. That issue was corrected. You may have a different issue, since your car is older.

 

[mknox]

Well, the issue as reported was affecting the Ds, and perhaps other newer cars. That issue was corrected. You may have a different issue, since your car is older.

Again weird. The Tesla rep who stopped by my office with a brand new P90D was getting 80/80 amps at my station, but my early 2013 S85 only sees 79/79.