Saturday, December 28, 2013


After testing the Fiero last week and and looking at the log files to try and determine why it was tripping, I discovered that I had the battery pack voltage reading to the controller coming off of the positive controller terminal, after the contactor instead of at the battery, so used the extra lead that was running under the car to take the reading from the battery pack.



Synkromotive told me to check the negative battery leads and sure enough, I had not fully tightened the one going into the negative terminal of the controller properly, so tightened it up.

Then the battery Low voltage fault and Low voltage limit settings were lowered to 60 volts and several throttle ramp ups were done. With the battery pack lower voltage limit settings lowered, I could not get the controller to trip when just revving the motor, even with some quick accelerations. 

The car was taken for another test drive and it did much better but still tripped when going from third to fourth under moderate acceleration. I have the battery low fault and low limit both set at 60 volts, so am going to try to raise the battery low level limit to 80 and the low level fault at 30 volts. The controller may be set up to back off when the voltage gets down to the low level limit and if I set the fault voltage quite a bit lower, should not get down far enough to trip.The voltages have never been that low in the log files but there may be some noise under heavy acceleration that is making the controller think it did.

Below is the video of the first test drive last week that my son edited for me.

There is still much to do on the car but on the One Year Anniversary of starting the rebuild, I have made one small step!

More next week,

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