High Power Wall Charger - Tesla recommends temporarily cutting amps

[bluetinc]

Yep, I don't always but usually once a week I go from home to Frederick (30 miles) to Baltimore (60 miles) and back again, total ~180. At highway speeds etc, that's most of a regular charge. Then home for an hour before heading downtown to DC to meet up with friends for activities/dinner (20-30 miles each way). All in all, yes, being able to charge at 20 kW/h takes the sacrifice out of it for me. Setting aside my solar system, this area doesn't have any real peak/off peak rates so when I charge is largely irrelevant to cost.


Peter

Can I ask? Why do you need to charge so fast at home? Do you run your batteries down that far each day? I can't bring myself to charge in ON-peak hours because of the rates. Just curious, I'm not being sarcastic.

 

[FlasherZ]

That only makes sense if the car is the problem. Which actually makes sense, since the car is the thing that controls the power flow.

The car isn't the problem, unless it's drawing > 100A when it says it's only drawing 80A, but then we'd see some circuit breakers tripping too. The firmware could have the car do something differently so that too much current isn't drawn, I suppose.

The fuses they're using are extremely fast-acting fuses, but even then they should not be blowing under these circumstances.

If you have the need to charge at the highest rate prior to Tesla's official fix (likely another fuse supplier), you can obtain 2 class T 100A fuses type JJN (300V) and replace them.

 

[pilotSteve]

The car isn't the problem, unless it's drawing > 100A when it says it's only drawing 80A, but then we'd see some circuit breakers tripping too. The firmware could have the car do something differently so that too much current isn't drawn, I suppose.

The fuses they're using are extremely fast-acting fuses, but even then they should not be blowing under these circumstances.

If you have the need to charge at the highest rate prior to Tesla's official fix (likely another fuse supplier), you can obtain 2 class T 100A fuses type JJN (300V) and replace them.

I can confirm that my PoCo checked the load at my meter feed and when my car showed 79A/232V that was EXACTLY what their test equipment shows was being drawn by the car.

 

[yobigd20]

Can I ask? Why do you need to charge so fast at home? Do you run your batteries down that far each day? I can't bring myself to charge in ON-peak hours because of the rates. Just curious, I'm not being sarcastic.

there is no 'on peak' vs 'off peak' rates in our area. so whether we charge at 2pm vs 2am it makes no difference.

 

[FalconNinetyD]

Mods, perhaps this thread should be made a sticky for the sake of saving some folks from blowing fuses, who might not have received the word from Tesla?

 

[brianman]

That only makes sense if the car is the problem. Which actually makes sense, since the car is the thing that controls the power flow.

They told me the logs indicated it was not a hardware problem with the vehicle. Note the underlining is mine.

 

[Arnold Panz]

Remember...problems like this are to be expected for the first year or so! Nobody's perfect. I'm happy about their communication on this, and happy about their commitment to working with us and "making things right."

What communication?! This announcement is buried somewhere in the Tesla website, not in a press release or blog post or anything. They know who have HPWCs and couldn't bother e-mailing those who have it (or sending a note on-screen)? I didn't see this until now and am glad I haven't blown the fuse yet because I've been charging at 80 amps. But I wouldn't have a clue without someone alerting me and these message boards, which I'm sure a lot of people with HPWCs don't read.

This is very poor to non-existent communication on Tesla's part, IMO. I don't mind the hiccup, but don't bury it so much that owners don't know about it!

 

[FlasherZ]

What communication?! This announcement is buried somewhere in the Tesla website, not in a press release or blog post or anything. They know who have HPWCs and couldn't bother e-mailing those who have it (or sending a note on-screen)? I didn't see this until now and am glad I haven't blown the fuse yet because I've been charging at 80 amps. But I wouldn't have a clue without someone alerting me and these message boards, which I'm sure a lot of people with HPWCs don't read.

This is very poor to non-existent communication on Tesla's part, IMO. I don't mind the hiccup, but don't bury it so much that owners don't know about it!

That only further supports my belief that it's a bad parts problem in the HPWC. Many owners are charging just fine with the HPWC at 80A. If you call and complain that yours has faulted, they send you new fuses and point at their web site post until they get a new fuse supplier tested.

 

[William13]

My car had one of the internal chargers replaced last week after it succesfully charged at 80 amps. The problem for mine was in the car. The power has been clean. This issue (OP) stills allows charging at 80 amps but if the internal fuse is a problem then you may want to only do this if you have a back up plan.

 

[FlasherZ]

My car had one of the internal chargers replaced last week after it succesfully charged at 80 amps. The problem for mine was in the car. The power has been clean. This issue (OP) stills allows charging at 80 amps but if the internal fuse is a problem then you may want to only do this if you have a back up plan.

You likely had a different problem. This is very clearly a problem with HPWC's in that they blow one of the 100A fuses designed to protect the device from overcurrent.

I had another acquaintance of mine reach out with a blown fuse experience this weekend via another forum. He wasn't happy to hear that Tesla hadn't communicated this more widely, either.

 

[neroden]

Disappointing to say the least.

I call BS on their "disturbances on the utility voltage" excuse. The parts are fast-acting fuses, rated at 100A, max 300V. The fact they're blowing at < 80A means "defective parts".

Tesla's description is vague and non-technical, but from "trips while using a hair dryer" and "disturbances on the utility voltage" I wonder if it's actually some form of GFCI which is tripping, rather than a fuse. Even though they say "internal fuse".

 

[Arnold Panz]

FYI, I contacted Tesla about this to find out why there was no communication on it. I was told that this problem only related to a few people with HPWCs, and so they are limiting the e-mail with the link to the website to only those people who they know (or think) have this issue, which isn't the majority of current HPWC owners. They're working hard to figure out what the problem is, but unless Tesla contacts you directly on the touch screen in the car, this isn't a problem you need to concern yourself with.

Chalk this up to growing pains -- they know that their communications aren't ideal yet, and are working on the best way to go about communicating with customers so that the right people get the information they need, and others aren't given incorrect or misleading information. TMC certainly doesn't make their life any easier

 

[FlasherZ]

Tesla's description is vague and non-technical, but from "trips while using a hair dryer" and "disturbances on the utility voltage" I wonder if it's actually some form of GFCI which is tripping, rather than a fuse. Even though they say "internal fuse".

No, it's actually 2 current-limiting fuses (like the main fuses that used to protect most of our homes years ago) in a very small package. Class T, 300V (JJN), 100A. They're very visible when you open the HPWC.

They look like this:
Fuse, Class T, 100 A - Amazon.com

 

[ShortArc]

A little off topic. I bought a five pack from automationdirect.com, here:

TJN100

They seem to have pretty good prices (same Edison brand as is in my HPWC).

 

[mitch672]

My Model S just updated to 4.3 2 days ago, I have a 75A OpenEVSE, I noticed today that the amperage setting had been lowered to 60A on the charging screen (Presumably by Tesla), as its normally set to 75A.. They think I have a HPWC . I set if back to 75A, lets seen if it stays their on tonight's timed charge (I charge shortly before leaving for work to minimize the time at %90 SOC)

I also emailed them about buying a HPWC (long story), anyway they tell me after the backorders are filled, it will be listed on the Tesla web store, but it might not be until June or July, yikes.

 

[jweinstein]

My Model S just updated to 4.3 2 days ago, I have a 75A OpenEVSE, I noticed today that the amperage setting had been lowered to 60A on the charging screen (Presumably by Tesla), as its normally set to 75A.. They think I have a HPWC . I set if back to 75A, lets seen if it stays their on tonight's timed charge (I charge shortly before leaving for work to minimize the time at %90 SOC)

I also emailed them about buying a HPWC (long story), anyway they tell me after the backorders are filled, it will be listed on the Tesla web store, but it might not be until June or July, yikes.

Mitch,

What is the ideal state of charge to leave the vehicle in? I thought standard mode at 90% of the battery's capacity was best for maximizing the life of the battery pack?

Josh

 

[mitch672]

Mitch,

What is the ideal state of charge to leave the vehicle in? I thought standard mode at 90% of the battery's capacity was best for maximizing the life of the battery pack?

Josh

I don't think we know, but why not leave it lower overnight, since I have the dual chargers, I can top it off at near 62 miles/hour, it also has closer to the full standard charge when I leave (because vampire losses haven't run it down yet). We do know that very high SOC should be avoided for long periods of time (one example a full range charge). It may not matter much, I'm probably being overly cautious/paranoid, but with the timer now, I can do this easily.

 

[gsxrex]

FYI, I contacted Tesla about this to find out why there was no communication on it. I was told that this problem only related to a few people with HPWCs, and so they are limiting the e-mail with the link to the website to only those people who they know (or think) have this issue, which isn't the majority of current HPWC owners. They're working hard to figure out what the problem is, but unless Tesla contacts you directly on the touch screen in the car, this isn't a problem you need to concern yourself with.

Chalk this up to growing pains -- they know that their communications aren't ideal yet, and are working on the best way to go about communicating with customers so that the right people get the information they need, and others aren't given incorrect or misleading information. TMC certainly doesn't make their life any easier

I just got my update to 4.3 (had 4.2 since I picked up at the factory about a month ago). Set the scheduled charge. Once I plugged the HPWC in, I noticed that my charge rate was dialed back to 60A. Once I tried to increase it, I got a pop-up window with the notice, and a link to the website with the full text posted earlier in this thread.

 

[jweinstein]

I just got my update to 4.3 (had 4.2 since I picked up at the factory about a month ago). Set the scheduled charge. Once I plugged the HPWC in, I noticed that my charge rate was dialed back to 60A. Once I tried to increase it, I got a pop-up window with the notice, and a link to the website with the full text posted earlier in this thread.

View attachment 19588

I had the same exact thing happen to me as Arnold. I just got the 4.3 update today; however, I was able to override the 60A level and set it to 80A. After driving about and returning, the charge current reset to 60A.

 

[clmazin]

Interesting. "Early Wall Connector."

Are all current HPWCs "early"?