More Driving Stats

I've had the car registered for almost 2 weeks now and have racked up 90 miles of driving. I had some clients from Boeing in for a review at work this week and I got to impress them with the car.

Efficiency tends to be in the range of 210-240 Wh/mile depending on how many times I have to stop. I've got RTD explorer working and tracked the temperature of the controller. On a 103 °F day it got up to a peak of 129 °F at the end of an acceleration from 0-50 mph and quickly drops down to 124 °F. If I coast to a stop at a light, it's down to 117-120 °F within a few seconds and seems to stabilize there. So I'm guessing the temperature of the coolant in the system stabilizes to around 117 °F or less (<15 above ambient?) since it's no different after 11 miles of driving.

I've been experimenting with charging. I don't have a heavy duty extension cord yet, so I have to string two regular (probably 16 awg) extension cords together. Originally I had an old computer cable pigtailed to the inlet wires in the loop too. That was bad because that wire was 18 awg and it got hot! All the internal wiring is 10 AWG in anticipation of wanting to charge at 20 amps or higher. If I charge the car at 5.0 amps, the clamp meter reads 14.5 or so Amps rms in from the house 120v line, and a 15 amp circuit breaker would eventually trip. So I've either had to drop down to 4.0 amps or run a third extension cord through my garage door and plug into the 20 amp outlet in the laundry room. Not great for charging when it's 118 °F outside. At 4 amps it takes about 5.5 hours to charge 22 miles (around 21 Ah). At 5.3 amps it's down to around 3 hrs 50 min. When I get a 240v 30 amp outlet installed and am brave enough to try it, I should be able to charge it in about an hour if the charger doesn't get too hot.

In the meantime I've been working on the BMS. The head board is complete and one of the slaves is complete. I've been modifying the code Joe sent me and think it's about ready to test. Unfortunately I completely missed a bunch of connectors in my order and have to wait until July 2nd for Mouser to get them here, so I can't do any testing until then.

So with no car work that needs to be done, I'm focusing on a few things I've been neglecting around the house. My wife is really happy that I cleaned out the garage and she can park in there again! I also tried my hand at cleaning the air conditioner to try and make it more efficient. The bozos who installed the unit in my attic put it in backwards so the access panel faces into a wall! I've had problems with it not draining properly because there's a bunch of sludge built up in the drain pan that I've never been able to clean out. Well, we've got a ton of family coming over on Sunday and it's supposed to be around 118 °F out so it needs all the help it can get so I bite the bullet, got up at 5:30 this morning and head up in the attic. After nailing down some boards I can lay down on and an hour and a half of cursing I managed to get the access panel off. Another hour and I've vacuumed all the sludge out and sprayed down the evaporator coils with some cleaner. Hopefully it was worth the effort. It's currently 115 °F outside and 76 °F inside. So far so good but the forecast is for 122 today.

I've only got two more weeks on my temporary permit to test out the car. I'd love to have the BMS functioning by the end of that before I take the 40 mile trip to the MVD, so hopefully I'll have enough time over the 4th of July weekend to make that happen.

Stay cool!