Sunday, October 5, 2014

TODAY IS A BETTER DAY

Sunday morning I went out to try and adjust the Fiero shifter linkage, armed with the shift position diagrams that were posted yesterday, and after pinning the shifter in third gear, disconnected the shift and select linkages at the tansaxle. After moving things around a little, I found that the select linkage was actually trying to lift the shift stem going down into the transaxle. This time I made sure that with the lever on the transaxle in the correct position, the cable could not push it up farther, causing the shaft to lift. Then the shift lever was put in the correct position, the play in the cable was taken out and then the connector tightened. There seems to be some play in one of the rods on the shifter and on one on the transaxle linkage, so that is probably the areas I will check out in the future. For now, it's working, so I am not going to mess with it.

The shifter went through all of the gears smoothly, while sitting in the driveway, so reverse was selected and the car backed up to pull out onto the road. Second gear was selected and the car moved forward out onto the street in front of my house. The shift to third and then fourth was fairly smooth, so I decided to run it around and make a pass back down the interstate. The car accelerated smoothly from second, to third, to fourth gear and I leveled the speed out at 60 mph. As I progressed down the highway, the current went as high as 503 battery amps at 91 volts and 576 motor amps at 79 volts. I believe these cells are only rated at 350 amps or so and appear to have been designed for higher voltage and lower current. When the other two packs are installed, the pack should not see such a drastic sag and I should be ok.


VOLTAGE GRAPH

As shown in the graph above, the battery volts and motor volts are inversely proportional and actually were almost the same during the acceleration onto the interstate. I wanted to put battery and motor current on the graph but it kept formatting so that voltage just looked like a strait line, so did not really show anything.


TEST DRIVE SPREADSHEET

The Synkromotive Controller does a great job collecting data  and I really should have hooked up more inputs to it. I originally thought that my low voltage battery volts were limiting the controller but it appears the pack voltage is limiting the controller, as the low pack voltage limit is currently set at 90 volts. You know when you reach the limit because the car slows down and you can not accelerate back up to the same speed you were at before the controller started cutting back.

The pack voltage and current for each entry were multiplied, then each line added together for a 60 second period, then divided by the number of entries to get the average wattage. I was driving at 60 MPH so the average watts were divided by 60 and came up with 432 watt hours per mile. I may not have done this correctly, as it seems a little high but the emergency brake may have been dragging, so that may have been the cause of the higher than expected watts per mile number.

In about 4 hours the voltage has recovered to 125.1 resting voltage. The car has been driven 13.5 miles and has used 32.5 amp hours, so using 120 volts as an average, has used 3900 watts. Dividing this by 13.5 miles is 289 watt hours per mile.This figure seems a little closer to what I was expecting. 

The temperature is up to 56 deg today, the shifter is working much better, and I got another interstate test drive in, so today really is a much better day that yesterday!

If any of you are using the Better Place Packs, I would like to hear your experiences.

Thanks for visiting,

Randy
Post a Comment