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PEM, motor gets too hot -- fans failed

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Picked my car up today. Didn't overheat, but it wasn't that warm out and didn't take my usual route. Temp was on the last blue bar, though.

One thing they did was to remove the "sump cover" This is a plate the covers the area that had leaves in the photo I posted earlier (here). They want me to monitor the temps and report back to them. I was thinking that area was where the hose from the blower attached to the PEM, but apparently not. Wish I could have been there when they removed the PEM.
 
This is the heat exchanger for the charger. if blocked, you cannot charge at higher rates. mine got stepped down to 27A/44A instead of 60A. Also the fan worked at highest level without getting a proper result.

I had a Roadster stop at my house for some juice yesterday. I've got 70A but his VDS kept dropping to 53A/53A while his PEM felt very warm. It was a bit of a mystery to us but now I think he's got leaves blocking his airflow. I should have looked at his PEM temp on the VDS but didn't think of it. He's got a 2.5 with the new fan.
 
I had a Roadster stop at my house for some juice yesterday. I've got 70A but his VDS kept dropping to 53A/53A while his PEM felt very warm. It was a bit of a mystery to us but now I think he's got leaves blocking his airflow. I should have looked at his PEM temp on the VDS but didn't think of it. He's got a 2.5 with the new fan.

Mine is also blocked I think (as does the ranger). They should be coming out to clean it and upgrade the fan next week. However, we did a 1100km round trip this weekend to Coimbra (Portugal) from home (Madrid) and the biggest issue we had was when charging yesterday at 32A... It was a hot day (officially 39C) and in the midday charging place OVMS showed the external temp to be 53C!! This made keeping PEM and Battery cool very difficult and the charge current got restricted down to 10A.

As this was going to turn a 6 hour recharge into an 18 hour recharge we came up with a solution (Don't try this at home folks... water and electricity do not mix... but it did work for us)... PEM ice cooling.

We put *sealed*bags of ice on top of the PEM and waited to see what happened (we also put some snacks on top of the ice to cool them too):
PEM liquid cooling.JPG

While I wouldn't want to put bags of ice on the PEM regularly, on this occasion it worked and we charged at 32A after about 30 mins with the ice packs.

Of course the Model S has this problem covered. Maybe one day one of us will come up with a liquid cooling upgrade for PEM and motor...
 
If profitable a division that does Roadster upgrades does not have to interfere in S or X production. There is also good press that they would get supporting and updating the Roadsters and now S's.

I tell people all the time about my firmware upgrades and how I get a better car every time they do that. When service is brought up I tell them about the fans, the sound proofing, more fans, floor mats etc all free.

With add-ons like headlights, soundproofing, brakes (coming), warranty (probably), J adapter cords (not as good as Henry's black CAN) and carbon fiber bits for the Roadster already, I seems they are quite serious about free and paid upgrades.
 
I think that upgrade might be coming from TM itself.

How big of a gesture would that be to replace all the PEMs on the Roadster for free with a liquid cooled one. Won't happen since its expensive.
Just the R&D alone would probably be prohibitively expensive. What would you pay for a water-cooled PEM? (Rhetorical question.) What would it cost them to engineer it, test it, and then build it in the small numbers that might be ordered? How many Roadster owners would pay e.g. $20,000 for a water-cooled PEM if they live in a moderate climate and have had no problems in the first two or three years of ownership? 10%? 20%? I think I'd buy it, just to have the best, if it was a couple thousand, but if it was $25,000 I probably would not.

I can see arguments both ways: Taking really good care of Roadster owners is good publicity. And they're doing so now. But spending too much money on publicity, if the number of failures is small, and public attention is by then focused on the Model S, which does not have the same problems, is another matter. It might cost them less to replace out-of-warranty failed PEMs, if there are not very many of them, than spending big bucks to engineer and build a better PEM and offering it below cost. And if they offer it at cost, they might get few or no orders.

I hope they offer it, and at an affordable price.

The Ranger is coming today to do my one-year maintenance. I'll ask him what he thinks of the PEM issue. I.e. does he think PEMs are likely to fail in significant numbers between year 3 and year 6 (the extended warranty period)?