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Old 12-13-2005, 09:28 AM
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Join Date: Oct 2003
Location: Detroit Area
Posts: 1,359

Originally Posted by theisgroup
ae racer, i think i got you a little confused.

discharging: you should discharge at a high amp rate down to .9volts per cell. this is to train the cells to what you normally race at.

dischargers: these things only discharge the pack down to a set voltage. There are tray type which discharge each cell individually and then there are pack types, these do the whole pack. the tray type are usually called discharger/equalizers from a marketing standpoint. example is the integy 0-30. this is a rapid discharge at 30 amps and you can think of it as an equalizer because it is bringing each cell down independant of the other. The problem with this for 3800 is that the low cut off is 0volts per cell. This is where it does most of it's equalizing. because it hold cells at 0v volt and wait for each cell to get to 0 volt. if you try to use this at .9volt, what you will see is if the pack is not a match pack and fairly new, the lights go out but some of the cells will be lower the .9, some will be higher then .9 and some will be .9. because 3 cells are on one knife switch and 3 are on another.

equalizing trays: these are general low amp dischage and do most of there work around their cut off. you can use this as a discharger, but then you are not training the cells to discharge at high amp rate as you race.

so the theory is to train your packs!

High discharge until the pack is "empty" (this is thought of as .9 for ib3800) and then to equalize the cells to .9v/cell so that each cell is at .9v for storage.

or if you are using one product, then: high discharge until .9 for storage and then back on the discharger/equalizer for 1-2 min before you charge, just to equalize the pack. I believe this brings the pack below .9volts per cell, but you are not keeping them there for any length of time.

if i have missed any part of this please correct me. This is just my understanding from all the reading

The problem is again the Integy 0-30 tray is NOT an equalizing tray. First of all, while is does drain or discharge each cell individually, it does not stop discharging the cells individually once their voltage reaches a certain point. It keeps discharging the cells. Because of the layout and function of the 0-30 discharger, if the lights go out for one cell you cannot stop the discharging of that cell without stopping the discharge of 2 others.

You can argure that when all the cells have been brought down to zero that they are equalized. But this is not a good argument becuase you cannot store the cells at zero volts. Storing the cells equalized is the only way to receive any benefit of equalizing the cells. So in effect you are not equalizing the cells with this method.

The purpose of equalizing to help further "match" or make the pack act as one big cell. Storing all the cells in a pack at the same voltage will hopefully allow all the cells in a pack to accept the same amount of charge but also help each cell so it gives out the same amount of engery at the same rate as the other 5 cells in the pack.

Also, as you state "zero" is not seen as 0.9 per cell. Zero is seen as zero. 0.9 per cells is seen as the lowest amount of energy you can saftely store in the packs without negatively effecting the performance of the cell.
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