Spent all of last Saturday debuging Tim Wong’s Soleq DC wagon.
– Tim designed and built an excellent bar graph BMS. See the picture.
– The pcb files and software are on his site for free.
– Tim’s BMS can monitor 18 batteries.
– My truck would have 18 groups of 14 cells to cover all 252 cells. Nice fit!
– He has an improvement that isolates the pack from the dash electronics.
– Tim is a mechanical engineer. So there is hope!
– Car has a DC motor know as a SepEx for separately excited.
– Car has 200 amp regen!!
– Found an open circuited 5.1v zener in the driver circuit for the armature circuit.
– The Armature circuitry had zero current output.
– We lacked a scope so debug was limited.
– The Field circuitry measured 15 amps output and was working fine.
– The main transistor was a 2N3773 NPN Power transistor in a TO-3 case.
– Maybe 100 transistors total.
– 6 boards for forward, 3 for regen.
– Found and removed a ground fault in the pack so the charger now works.
– The new lead acid 6v batteries were a bit bigger and were stuffed in by a mechanic and the compression cracked the bad battery.
– Tim expects EV’s to be as reliable as a Toyota Camery. He is willing to drive a curtis powered DC car to get reliability.
– He tells me the other owners all have had controller failures.
– Tim’s URL: http://home.earthlink.net/~evtkw/
This past week my truck hit 9k miles on the nicad pack!
– A major pack watering is due any time.
– The new charging curve has minimized water usage of the cells.
– Watered last August!
– Many of the bussbars have a tapped hole which would make for a nice attachment point for a BMS sensor.
– Reducing work load on the USE boards by refusing any new repairs so that I can get back to the other projects such as the A123 Lithium module.
– Passing the work on to Chris.
– I’m an R&D guy at heart and need to stay there.
I just barely got accepted into the Clean Air parking program for
Downtown San Jose where I park and charge my electric truck often. The
list of vehicles in the link below does not have US Electricar or
Solectria vehicles listed. That’s why I was initially declined for the
parking decal. After they finally figured out that my registration has
the fuel listed as ‘E’ for electric, they gave me the ok to receive the
sticker. So, if you are a San Jose resident and want the parking
sticker that allows you to park for free, make sure you circle the fuel
type clearly on your registration to remind them to look! I talked to
them twice and made sure that they know that Solectria and US
Electricar vehicles are genuine EV’s. They may not remember!! I also
let them know that many home brewed vehicles with have the fuel type
‘E’ listed on their registration as well.
The decal allows free parking at the garages listed and at all parking
meters. The only one not on there that has pay parking is the SJ
Convention center. There is an EV spot there with charging however.
The decal is $30/year.