First family Sunday test

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TheStig

Well-known member
Joined
Jan 5, 2015
Messages
100
I don't have exhaustive notes for raw data points but we gave our B a good workout today.

Extended range charge overnight, used departure time for the morning warm up in the garage connected to charger.

Drove 9 mostly highway miles before the SOC dropped from 100 to 99%. I think the GOM predicted 93 miles available after resetting at the start.

Continued to the destination another 20 miles on highway at 65 to 70 mostly cruise controlled.

Stopped for a kids birthday party.

Next leg was about 7 miles of in town driving, time to test out the JESLA chargers portable design. I'd built 2 adapters to convert a old style 10-30 30amp dryer plug to L14-30. That allowed me to use an existing 25ft generator extension cord and reach from a family members dryer plug to the driveway. JESLA powered right up and charging began. Mostly as a test so I would know it worked.

Charged maybe 20 minutes and my wife took it and ran errands for 22 more miles.

Back on the JESLA while we had dinner.

Left for the 32 mile drive home with 66% SOC, Arrived home with 25% SOC.

Put the JESLA back on the 50 amp circuit for some real charging.

We never broke 40 degrees here in CT today, most of the day was in the mid 30's. 2 adults, 2 kids and plenty of junk in the trunk, so well loaded.

In total 89 miles averaging 2.3mpKwh, 38mph, in 2h21m drive time.

Assuming I have this right 89/2.3x$0.15 is $5.80 for the day.

Either of our gas cars might have averaged 20mpg over the same trip, swilling premium for a total of $13.45.

Couple notes, there is a very big charge time difference between the JESLA running at 42a off my 50a circuit at home vs. the maybe 24a it pulled off the 30a dryer circuit. Light years better than the emergency charger would have done, but very noticeable slowdown.

Without the JESLA being portable and the ability to reach the dryer outlet the 22 miles of side trip would have been a very bad idea. The SOC would have been in the low single digits for sure by the time we'd have gotten home.

I didn't log every piece of data today, but after 600 miles of ownership we are figuring out what the car is capable of and it is going well so far. I expect it only improves with warmer weather.
 
Stig,

Thanks for the note. I will look into the JESLA thingee to plug into in-laws homes. Curious though, I always calculate mileage based on mpKwh. At 2.3 even with extended range, I am not sure you would have made 89 miles on your start the day charge. I must be missing something important.
 
I agree, 89 miles doesn't feel possible with the car loaded and 35 degree temperatures. Also the ride home isn't anything resembling flat, though you capture or coast the downhill's it seems to really zap on those hill climbs.

It was the charge I was able to add mid trip with the JESLA that made it possible.
 
I have experimented with my OpenEVSE. 40A or 42A makes no difference. Once the car sees the 40A pilot it is maxed out. The J1772 max of 80A would make no difference. It also follows the pilot. I have charged at 40A, 30A, 24A, and 16A.
 
I'll assume the JESLA pilot is 40A with the 14-50 plug attached. My clamp on current meter measures 40a on one phase and 42a on the other, something like that. Close enough for the margin of error in current draw or metering.

When you attached the JESLA 10-30 plug, the pilot signal drops to 24A and that is a very apparent increase in charge time.

I agree with other posters that the 7kw / 30A chargers (on a 40A breaker) like the Siemens are plenty for the B Class. But dropping to a 30A breaker with a 5.8kW max rate wouldn't be the best for a car with a battery this size.
 
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