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Old 06-28-2004, 11:11 PM   #1
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Default discharger voltage cut-off

i've just made myself a discharger, and just wondering what a good cut-off is. i've heard of 3.6V-6.3V, but what is the most practical? where is too far, and whats not enough?
unless you have something constructive to say, please don't say anything at all.
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Old 06-28-2004, 11:56 PM   #2
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1st you must determine what packs will you discharge NI-CD or NI-MH.

if you will discharge ni-cd cutoff can be set to 0volts. if you will discharge ni-mh packs you must set it at 6volts cutoff.


why 6 volts and not 5.4 volts? - because at 5.4 volts one of the batts in your pack will reach 0 volts cause not all batts in the pack will reach .9 volts at the same time. at 6 volts the battery with the lowest voltage will be at .9

4 volt cutoff for 4 cell packs
6 volt cutoff for 6 cell packs.


after your discharger cutsoff you should equalize your batts.(if possible)
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Old 06-29-2004, 01:37 AM   #3
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Quote:
Originally posted by S-T-R-l-K-E-R
why 6 volts and not 5.4 volts? - because at 5.4 volts one of the batts in your pack will reach 0 volts cause not all batts in the pack will reach .9 volts at the same time. at 6 volts the battery with the lowest voltage will be at .9
With a pack that is out of balance, one cell could be at almost any voltage when the pack is at 6v.

I would run with 0.9v per cell, it's the "industry standard".
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Old 06-29-2004, 01:58 AM   #4
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5.4 volts-cut-off=.9 volts per cell
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Old 06-29-2004, 02:00 AM   #5
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cell equalizing isn't required if discharging for storage.
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Old 06-29-2004, 02:08 AM   #6
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unless the pack has some really crazy stuff going on, all the cells will be at a similar voltage at the same time.
0.9v/cell is what i was thinking, thats what they use when matching cells.

and yeah, trigger is right. 0.9v/cell is 5.4v, and 6v would be 1v/cell.
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Old 06-29-2004, 02:15 AM   #7
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What kind of discharger did you build?.does it discharge the cells independently of eachother (like a trey type)or by connecting the pos and neg to the device and doing the whole pack at once.....what classes you run can also make a difference in how you might want to maintain and store your batterys......
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Old 06-29-2004, 02:18 AM   #8
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the discharger does the whole pack as one, not the indevidual cells. im racing in rebuildable stock, with zapped matched GP3300's.
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Old 06-29-2004, 02:22 AM   #9
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Might I suggest that you put the cutoff for that fast discharger at 6v and then equalize at 0.9v/cell or 5.4v/pack.
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Old 06-29-2004, 02:40 AM   #10
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For stock racing where peak voltage,and low internal resistance,is most important....try a six amp charge, discharge to around 6 volts ,it's not that important as long as your in the ballpark) then "most importantly" pick up a trey if you donty have one already(integy just came out with a new equalizer and it's only around 16 bucks) either bring each cell down to .9 volts.....or bring them to zero as explained on SMC's website and deadshort them until your ready to run them.....this will lower the resistance and give you a little higher volts across the discharge at the cost of a very small amount of runtime..like 10 to 20 seconds......this is what I have done with all of my packs for stock class racing for over a year with great results......mabe try it on one of your packs to see which one is better for you
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Old 06-29-2004, 02:50 AM   #11
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Quote:
Originally posted by Joe B
...integy just came out with a new equalizer and it's only around 16 bucks...
What's it's called? Do you have a link? It didnt seemed to be on the Integy site...
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Old 06-29-2004, 11:21 AM   #12
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Yea cole, it's on the integy website.....Part # E2027 ........go to the discharge section it retails for 19.99 but Iv'e seen it in the stores for 15.99............
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Old 06-29-2004, 11:26 AM   #13
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http://integy.automated-shops.com then select dischargers from the choose catagory
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Old 06-29-2004, 11:29 PM   #14
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Quote:
Originally posted by sosidge
With a pack that is out of balance, one cell could be at almost any voltage when the pack is at 6v.

I would run with 0.9v per cell, it's the "industry standard".
yes one when you set a cutoff at 6V you are sure that ALL your cells are safe from cell reversing . thats why you have to equalize to be sure that you bring down all your cells at 0.9V/cell ="industry standard".

yes .09V x 6 = 5.4V thats with a perfectly matched pack. but in reality not all batts are created equally. " a pack that is out of balance" means that a couple of batts w/in that pack may have a longer runtime than others, or may have a higher voltage reading than some. so when this stronger battery hits your so called -"INDUSTRY STANDARD" without doubt that the weakest batt have reached 0.0V eons ago.

thats why you have to cutoff at 6V to prevent the weaker batts from reaching at 0.0V. then equalize to get the "industry standard" for all cells
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Old 07-01-2004, 03:02 AM   #15
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Joe B: The new Zero-Equalizer looks interesting, but there isn't much info on Integy's site. Do you know in what way it is different from the Activator?
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