Hi All,
I spoke with Pro Trak today and have some answers for you. The short answer is, some meaningless results were eliminated so you would not get a false impression of your cells. The best way to explain this is by an example.
Given a discharge cut off of 1v per cell this is the end volts at the end of discharge.
cell 1 .95
cell 2 .50
cell 3 1.03
cell 4 .86
Cell 2 has hit .5v, this triggers the Pro Trak to stop the charge
Cells 1,2 and 4 have gone past 1v, the count for those cells have been terminated and recorded when they hit 1v (which you specified). Cell 3 has not got to 1 volt it's numbers cannot be recorded to the 1v point therefore any match numbers given will be innaccurate.
Up to this version the pack match has been an average of the percentages from each cell. with a 1v cutoff cell 1 would be 95% cell 2 50% etc. When you have one high cell and one low cell they will tend to average each other out and you will get a false indication of a reasonably matched set of cells.
The higher you set the cut off point, the more likely it is that the cells will all reach that point before the first one gets to 0.5v. However, the higher the cutoff the lower the total capacity of the pack will be. My thoughts about this is - Your pack is only as good as your weakest cell - When your weakest cell is done you aren't going to be getting much speed in your car on the track. Therefore any extra time, in the other cells is worthless.
If you have any questions please ask.
Chris.
Last edited by crimson eagle; 11-20-2004 at 09:18 AM.