My HPWC almost melted down!!!

[DoctorJJ]

Sorry, was away on a mini-vacation. It was charging at 80 amps. The breaker in the box is 100 amps. I checked it and it was barely warm. My electrician went overkill on everything on my side. No no worries about heat at the breaker box, the breaker, or the wiring to the HPWC.

Yes, I believe the crimp under the shrink tubing failed. That was clearly the hottest point.

Tesla did call me back promptly, and sent me a new HPWC and offered to arrange for or reimburse for an electrician to replace the HPWC. They also want mine back to inspect it. So they are definitely doing their part.

Also, doesn't everyone own a FLIR? I love my i7. I use it for all kinds of things.

 

[sorka]

The Seek may be cheap but it's accurate, high res, and you can take photos and videos and upload them on the spot.

 

[spaceballs]

I have the Seek Thermal device for my phone. Cheap man's FLiR @ $199.

Definitely not as good as the real thing, but it finds the heating / cooling leaks just fine and measures the temps reasonably well. I use it to find where the honeybee clusters are located within the hives in winter. Random factoid: at temperatures below ~55 deg F, honeybees gather tightly into a cluster that maintains a 93 deg F internal core, so it's easy to see where they are in the hive just by taking a thermal pic from the outside.

I had i3 (is good enough compared to i7 for me), but too bulky to carry all the time, so I went with Flir One and Seek (both cheap also).

 

[DoctorJJ]

I had i3 (is good enough compared to i7 for me), but too bulky to carry all the time, so I went with Flir One and Seek (both cheap also).

I've got a Flir One as well but it's not the device that a dedicated device like the i7 is.

 

[andrewket]

I've been wanting an IR camera for awhile. The reviews on the seek seem mixed. The flir one gets better overall marks for picture quality despite the smaller sensor, but appears only to be available for the 5/5s (I've got a 6+). Sooo.. ended up not buying anything.

 

[spaceballs]

I've been wanting an IR camera for awhile. The reviews on the seek seem mixed. The flir one gets better overall marks for picture quality despite the smaller sensor, but appears only to be available for the 5/5s (I've got a 6+). Sooo.. ended up not buying anything.

Always could buy an used 5, or use ipad air/mini or your 6+ and use a apple extension cable (might have to be jailbroken, I can't remember).

 

[DoctorJJ]

New HPWC is installed. I charged at 80 amps from 40 miles to 230 and the highest that crimp got to was about 210. Personally, I think having to self limit the charge rate is a bandaid. We shouldn't have to worry about that.

 

[kennybobby]

That still seems too high to me. The new crimp was probably done the same way as the previous unit. Look at how flat the lug was smashed in the pictures--that is not a proper crimp joint. A flat smash of a lug allows voids in contact area.

If you have a good voltmeter you would be able to measure the voltage drop while charging at 80A across the short jumper wires from the contactor output to the output terminal block, and then calculate the resistance of the crimp joint.

Here is how diy guys roll their own, and sometimes you have to check your work to make sure there are no voids:

 

[m6bigdog]

New HPWC is installed. I charged at 80 amps from 40 miles to 230 and the highest that crimp got to was about 210. Personally, I think having to self limit the charge rate is a bandaid. We shouldn't have to worry about that.

Yep, yet the reality is the HPWC is under a lot of heat stress , thermo cycling at 80 amps and if you are charging overnight the 80 amp charge rate is of no real advantage what so ever over a lower charge current.
HPWC would most likely last forever at a 40 amps charge rate (25% of the internal power dissipation of 80 amps), is more efficient and when you wake up in the morning the battery will have reached the same daily charge limit and suffered much less stress.
IMHO, given the current packaging and circuit design the HPWS should have been limited to a lower continuous current rating and then they would be much more reliable.

Now, if you only have a couple of hours to charge and need to stick in a 100 miles of range then crank it up to 80 amps!!

FWIW, when HPWC is operated at 56 amps the internal power dissipated is 50% of the 80 amp power dissipation.

It may seem like you're not getting your monies worth from the HPWC at 56 amps and even less at 40 amps, however the HPWC is what it is and at this point it is more about operating it for better reliability and efficiency, since the actual daily charge will be the same kWh during the overnight charge.

I say beat Tesla up for the lack of reliability and failure rate and maybe someday they will redesign the HPWC with better cooling and more margin for internal power dissipation; but until that day, it is better to just dial down the charge current.

 

[Johan]

To me it's obvious that Tesla is cutting it close with these 80A HPWC in the US.

In the EU Tesla doesn't supply a HPWC but if you want to charge >10 kW you need to get a third party EVSE. This is due to us using 3-phase power and, I suspect, Tesla didn't want to create yet another HPWC solution for the EU. In my opinion a wise choice. If you want to charge at 10kW you get a red CEE plug (3-phase, 400V, 16A) and use the UMC - we've had zero reports of heat issues.

I should add though that a third party EVSE that does support 22kW charging in the EU is quite a bit more expensive than Tesla's HPWC solution in the US. This tells me Tesla has perhaps chosen components and an engineered the HPWC with price in mind.

 

[wk057]

I charged at 80 amps from 40 miles to 230 and the highest that crimp got to was about 210.

That's pretty significant. Wire/junctions are rated at most for 90C temperatures (194F), usually. There is some wire with 105C insulation (221F) but I haven't seen many things with junctions rated for 105C. Honestly I haven't seen many things with junctions rated for 90C, either.

I've not seen temps that high in either of my own HPWCs. The only thing that gets near that hot in either of mine is the power resistor that is part of the contactor driver circuit.

I don't know the engineering calcs behind the HPWC design, but 210F at a junction seems like it warrants some monitoring. So at the very least I'd keep an eye on it.

 

[FlasherZ]

That's pretty significant. Wire/junctions are rated at most for 90C temperatures (194F), usually. There is some wire with 105C insulation (221F) but I haven't seen many things with junctions rated for 105C. Honestly I haven't seen many things with junctions rated for 90C, either.

I've not seen temps that high in either of my own HPWCs. The only thing that gets near that hot in either of mine is the power resistor that is part of the contactor driver circuit.

I don't know the engineering calcs behind the HPWC design, but 210F at a junction seems like it warrants some monitoring. So at the very least I'd keep an eye on it.

The HPWC uses 105 degC cable. I agree the terminations are still an outstanding question.

 

[wk057]

The HPWC uses 105 degC cable. I agree the terminations are still an outstanding question.

Yeah, just took a look at that again. The car side cable is 105C.

The wire inside in question isn't very long and appears to have roughly the same section of writing exposed on both wires on the HPWC I have opened, which says that it is 105C TEW. Doesn't say a gauge on this section, but I'm guessing #6. With the thicker TEW style insulation it's a little too slim to be #4 I think. That would put it above the 90C NEC rating for #6 (75A). Seems like the bare minimum approach was taken with the HPWC on stuff like this.

Still unsure the junction temps for the components on the ends. I'd honestly be quite surprised if they were 105C rated as well.

 

[pgiralt]

I got a FLIR One - http://www.flir.com/flirone/ - before I used to rent one at Home Depot twice a year, for energy efficiency projects, but this has been fantastic.

BTW - the new FLIR One just came out a couple of days ago. Supports iPhone 6 and soon to support Android as well. They say 4x the resolution of the original and no more manual calibration. Not bad for $250. I ordered one and it shows up on Monday. Will post some pics with it when it arrives.

 

[FlasherZ]

BTW - the new FLIR One just came out a couple of days ago. Supports iPhone 6 and soon to support Android as well. They say 4x the resolution of the original and no more manual calibration. Not bad for $250. I ordered one and it shows up on Monday. Will post some pics with it when it arrives.

That's great - looks like a little bit of competition (Seek and others like it) have pushed FLiR to enter the arena of reasonable.

 

[Dbitter1]

BTW - the new FLIR One just came out a couple of days ago. Supports iPhone 6 and soon to support Android as well. They say 4x the resolution of the original and no more manual calibration. Not bad for $250. I ordered one and it shows up on Monday. Will post some pics with it when it arrives.

Ok, now my jaw dropped again. I must be getting old. Last time I looked, a IR camera worth any salt was about $10K. Please report in on it, I think I'll add myself to the list of people that have a FLIR lying around.

 

[andrewket]

BTW - the new FLIR One just came out a couple of days ago. Supports iPhone 6 and soon to support Android as well. They say 4x the resolution of the original and no more manual calibration. Not bad for $250. I ordered one and it shows up on Monday. Will post some pics with it when it arrives.

Where did you order from? I ordered one directly from flir today and it said 2-3 weeks. Amazon has no ETA.

 

[pgiralt]

Where did you order from? I ordered one directly from flir today and it said 2-3 weeks. Amazon has no ETA.

Ordered from FLIR direct two days ago when they announced it. It wasn't even showing up on Amazon yet.

 

[EchoDelta]

BTW - the new FLIR One just came out a couple of days ago. Supports iPhone 6 and soon to support Android as well. They say 4x the resolution of the original and no more manual calibration. Not bad for $250. I ordered one and it shows up on Monday. Will post some pics with it when it arrives.

Yeah, great value IMO.
The calibration of the first model wasn't so bad; but the resolution addition is great. I wonder how battery life gets affected, haven't read the specs of the new model.

//off topic

 

[kennybobby]

Let's keep this //on topic. Start a new thread for ir prices and don't hijack this one.

If the internal wires were 6 AWG and 12" long, then the heating at 80A would only be 2.6 Watts. That's not sufficient to raise the temperature to 210F.