DAY 13: Nov. 15th, 2008 - Saturday.
Day thirteen of the Santa Rosa Junior College Course -
DET-193. ELECTRIC VEHICLE CONVERSION.
We had three new projects appear in the class today.
Zap electric assisted bicycle.
Spike bought in a ZAP bike that seemed to having charging problems. I'm not sure that it actually got fixed, but the batteries were charged and a few people got to take it for a spin.
Electric Powered wheel chair
One class member brought one in that had been left for a long time at a repair shop. Pulling apart the controller she found a melted plug and a broken connection. This will be her project for next week.
Electric Fork lift
This was actually here last week, but nobody realized it was for us to work on. Nobody took it on yet today...
Yamaha Mini-Enduro C.1980
Willie designed and started fabricating the battery mounting box.
Don's car (1982 Plymouth Horizon):
The right bolts arrived, the clutch and pressure plate was mated to the Motor, and the Motor was put back in the vehicle! Yea Team!
Work continued on fabricating the rear battery box, and the frame into which it will sit. Mountings for the front battery box were worked on. Wiring continued on the component board
Ed's Car (VW Cabriolet)
Wiring, wiring and more wiring - Under the dash wiring and motor compartment wiring continued. The vacum pump system for the brakes was re-installed, 3 special EV guaues were installed in the dashboard, but not yet wired up. The middle battery box cover had been painted a shade of red and cut to fit the hole more closely. The vehcile was standing on its own feet (wheels) at last.
>>> cont. next column >>>
<<< Back to day twelve
Woody was left alone again this week.
Team Harley :
No team members where here again today, so no work was done.
The batteries had been charged during the week, and were individually checked. All fell between 13.1 and 13.3v which was a far cry for the first time they were checked (see blog day four)
A computer was hooked up and the car taken out for a 9.5 mile drive, while data was collected at different times and under different conditions.
A mechanical "clunk" was noted and will be investigated before the car is taken out again. At one time, all DC input to the Controller ceased and the vehicle started to roll to an ignoble stop on the free way, but Peter touched the regeneration switch and somehow it all came back on line.
Voltage sag is a problem as perhaps the Gel batteries cannot release their power quickly enough. As a result, it appears that the contoller starts to limit the power being released to the motor as it "thinks" the batteries are getting flat. One option would be to reduce that parameter to 150V as the reduction in power actally starts at a higher level - but that runs the risk of taking the batteries too low too often and reducing their lives even further..
Finally the State of Charge guage was found to be missconnecgted to the Key Swicth relay, causing it to only come on when the key was Off rather than ON. This was fixed and it now works as expected.
Back in the class room the one remaing team member (yours truly) wasted a lot of time learning how to import the data into an Excel spreadsheet in a way that kept the headers and made sense - but it finally got done properly.