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HPWC Dead

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So I'm having a pretty bad week with the car. First, I had a rim destroyed over the weekend (details here http://www.teslamotorsclub.com/showthread.php/17216-rim-damage) and today my HPWC stopped working. I held the reset button, nothing. Went over to the panel and saw the breaker was in the "on" position. I flipped it to off and back to on, still nothing. It's just dead. Any theories as to what this might be? Any help is appreciated as always.
 
Do you have any way to verify you are getting power to the HPWC?

I had a similar problem late last week - and it turned out to be a damaged breaker inside the panel. The electrician was out tonight and made some adjustments inside the panel and installed a new breaker - and my HPWC is working again.
 
Does your HPWC have a green light on? If there are no green LEDs at all, and your main breaker is ON, then you probably blew the internal fuse like many others (including me) have encountered.

This fuse blowing bug happens when charging at 80A, which is why the 4.5 firmware caps you at 60A for charging now.

I recently replaced the fuse in my HPWC, it wasn't too difficult, just annoying to work in the tight confines of the box.

/Mitch.
 
Mitch, thanks for the explanation. This is most likely what has happened. I was not able to find the fuse inside the box, is there a diagram I can refer to? The manual doesn't have anything of use that references this problem.

Does your HPWC have a green light on? If there are no green LEDs at all, and your main breaker is ON, then you probably blew the internal fuse like many others (including me) have encountered.

This fuse blowing bug happens when charging at 80A, which is why the 4.5 firmware caps you at 60A for charging now.

I recently replaced the fuse in my HPWC, it wasn't too difficult, just annoying to work in the tight confines of the box.

/Mitch.
 
Excellent, thank you. I will take a look tonight and put pics up once I'm able to fix this so others can see.

I should have taken pictures of the fuses - they're the ones that say "Edison" on them, little cylinders with big tabs sticking out top and bottom. You can see them in the upper left side of the HPWC when it's opened.

I bought my replacements at (I'm sure there are cheaper places).

AutomationDirect.com - The best way to buy industrial controls - low prices, fast shipping and superior service. Look for part # TJN100, 5-packs for $57.00.

/Mitch.
 
Is anyone consistently running at 80A with these replacement fuses? I just switched to a TOD pricing plan and need 80A to charge 0-full during the super off peak period.

The fuses I used are the same type, rating, and brand (same part #) as the originals. Messing with the rating or type is probably unsafe, so changing brands might be the only variable I mess with.

Something in the car (or charger) is drawing >100A on what is supposed to be an 80A load. Those fuses are doing their job.

I just got the 4.5 update (same day I replaced my fuse) - I could force it back to 80A, but i expect it to last some random amount of time and blow again. Still, I have 4 new ones left, why not?

/Mitch.
 
Something in the car (or charger) is drawing >100A on what is supposed to be an 80A load. Those fuses are doing their job.

It's more complex than that. :)

The fuses blowing do not mean that something is drawing more than 100A. Fuses are subject to a few other factors, including reactive power (power factor).

I posted a link here to the data sheet for these fuses with typical burn time and some theories on it. The burn-through chart goes up to 300 seconds. My current hypothesis is that the combination of the 80A current, the power factor of the chargers, and the sealed HPWC enclosure (NEMA-3R) all contribute to the fuses burning through. I've been told that Tesla is testing some modifications on local installs in the bay area and will be sending instructions based on their confidence in the changes.
 
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I wonder why they went with "EXTREMELY FAST-ACTING" fuses... I understand we're talking about high currents but I wonder if the reaction time of the fuses has something to do with the fact they're blowing so "easily".

From what I have observed, the type wouldn't matter here - the burn-throughs here are the result of prolonged current draw. The use of "slow-acting"/"slow-blow" are intended to instant in-rush currents like motor starts. Fast-acting fuses are less expensive and since there are no inrush current protection needs, they're the appropriate fuse type.
 
From what I have observed, the type wouldn't matter here - the burn-throughs here are the result of prolonged current draw. The use of "slow-acting"/"slow-blow" are intended to instant in-rush currents like motor starts. Fast-acting fuses are less expensive and since there are no inrush current protection needs, they're the appropriate fuse type.

Is the problem the heat that is generated during prolonged current draw, or other?
 
It's more complex than that. :)

The fuses blowing do not mean that something is drawing more than 100A. Fuses are subject to a few other factors, including reactive power (power factor).

Interesting info, thanks!

The main point I was trying to make was for those attempting to replace fuses not to try to put larger ones in. I'm spooked even to change brands, and will deal with blown fuses until Tesla comes up with a real fix.

/Mitch.
 
Is the problem the heat that is generated during prolonged current draw, or other?

I don't know for sure. I'm thinking that's a factor. Placing your hand on the upper left of the HPWC (where the fuses are) when it's operating will show just how warm it gets. When you figure it's a sealed enclosure, so that heat is trapped, it could certainly be a factor.

You could probably bake cookies in there. :)
 
I charged for the first time yesterday with my HPWC. At 60A I noticed that the ambient temperature in my garage was elevated. At 40A I had not noticed an increase. I could also hear the pack cooling system running. At 40A I had only heard it periodically. It was a warm day yesterday, so it may have been a coincidence. Either way, it was enough for me to start exploring ventilation options in my garage. Elon has been pretty clear: heat and high SOC are the worst for the battery. Exactly what charging in a closed garage provides :/