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Old 03-12-2006, 09:43 PM   #16
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Originally Posted by XingXing
Hi. I have been using my teamwave equlizing tray, it has given me a great deal of information about when i discharge me cells and would thought i will share with you all.

Basically i hook my pack to the teamwave, and will tell me the volt of each individual cell.

My charger can discharge up to 20Amps.

I found that if you use 20Amp discharge you should cut off the discharge at 6V. (average 1v per/cell) Any lower than this you will risk some cells going below 0.9v...

If you have unmatched packs then the cutoff should be higher, coz the variances in runtime would be more significant.

Also I have found that the lower the discharge rate, the higher the cutoff voltage should be set to to avoid going below 0.9v percell.

Moral is, never discharge your cells down to 5.4volts on your charger.your cells will definitly go below 0.9v when you do.
yep, its surprised me, what he said its true..
I've this test yesterday,
beside i voltmeter across batt pack,
I'm also put 6 voltmeter across each cell pole to measure each cell voltage during 20A discharge process,
then, when packs voltage drop to 6.2V zone (no reach 5.4V limit yet), one of the cell's voltage suddenly drop down to 0.7V from 1.01V something, then immediately I disconnect the pack...
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Old 03-19-2006, 04:23 AM   #17
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what i cant figure out is why discharge trays still exhist for because they are dead shorting each cell?? maybe a low current but its still dead shorting
whats a good setup up for gp3700? dead short or not im runing stock thats all
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Old 03-19-2006, 06:58 AM   #18
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will it be damaging for me to put 3800s on an Integy 0-30 for 10 minutes prior to charging?

i currently have the batman and the 0-30, would appreciate advice on batt care.
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Old 03-19-2006, 02:27 PM   #19
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Quote:
Originally Posted by Faiz
yep, its surprised me, what he said its true..
I've this test yesterday,
beside i voltmeter across batt pack,
I'm also put 6 voltmeter across each cell pole to measure each cell voltage during 20A discharge process,
then, when packs voltage drop to 6.2V zone (no reach 5.4V limit yet), one of the cell's voltage suddenly drop down to 0.7V from 1.01V something, then immediately I disconnect the pack...

glad to see that you confirmed it for yourself!
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Old 03-19-2006, 03:07 PM   #20
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Originally Posted by aus jd 2703
what i cant figure out is why discharge trays still exhist for because they are dead shorting each cell?? maybe a low current but its still dead shorting
whats a good setup up for gp3700? dead short or not im runing stock thats all
Not to sure what you're asking, but I think you've misunderstood two terms. Deadshorting is different from equalizing/discharging. Equalizing cells with a tray is so that each cell is at the same voltage and energy so they are as matched as close as possible before you charge them (in series). Deadshorting a pack is physically connecting the + and - ends of the pack to create a short circuit for the pack. This slightly raises voltage and decreases IR but at the cost of unrecoverable runtime. Deadshorting isn't recommended on the IB cells, and you should only do it for stock or 19T if you do deadshort a pack.
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Old 03-19-2006, 03:10 PM   #21
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Quote:
Originally Posted by zipp
will it be damaging for me to put 3800s on an Integy 0-30 for 10 minutes prior to charging?

i currently have the batman and the 0-30, would appreciate advice on batt care.
As sson as the lights go out you should disconnect. The 0-30 tray is not really an equalizing tray, as the discharge current is too high. I use the Batman to discharge the rest of the pack after I run it and store it like that. Before I charge I will put the pack on a low current equalizing tray. For GP cells I tray them overnight.
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Old 03-19-2006, 07:21 PM   #22
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hi guys. would just want to ask if the trinity real time 2.5 (equalizing tray) has a cut off? if it does, what is it? thanks in advance.
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Old 03-20-2006, 05:18 AM   #23
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hi guys. would just want to ask if the trinity real time 2.5 (equalizing tray) has a cut off? if it does, what is it? thanks in advance.

hi. cut off at zero.

u should look at the teamwave lightning. adjustable cutoff from 0.7 to 1.0

they are taking over here as the prefered discharge tray



cheers
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Old 03-20-2006, 05:21 AM   #24
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thanks for the reply!
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Old 03-21-2006, 02:09 AM   #25
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how much run time will i loose also in essence all resistor trays have a 0.0v cut off and i think (ive learnt alittle physics) and when a resistor gets to a low voltage the resistance gets less and less and at a point becomes 0 so that mean the wire form the short = dead short?
im just asking before i spend my hard earnt $$ lol
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Old 03-21-2006, 08:24 AM   #26
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Originally Posted by aus jd 2703
how much run time will i loose also in essence all resistor trays have a 0.0v cut off and i think (ive learnt alittle physics) and when a resistor gets to a low voltage the resistance gets less and less and at a point becomes 0 so that mean the wire form the short = dead short?
im just asking before i spend my hard earnt $$ lol
A resistor is rated at a certain load or resistance for a charge to pass through it. Using Ohm's law, Current = Voltage/Resistance so as the cell get's discharged the voltage lowers and hence so does the current. You can use a simple diode to build a cutoff. Most silicon diodes have a forward voltage drop of 0.7v which is a safe cutoff for any cell.
Also, you won't lose any runtime as long as your cells don't go into cell reversal. I keep my GP cells trayed for days.
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Old 03-22-2006, 12:07 PM   #27
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I read it somewhere ......, when people discharge IB cells down to 0 volts, it damage mAh capacity while it gets higher peaked voltage.
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Old 03-22-2006, 12:11 PM   #28
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I read it somewhere ......, when people discharge IB cells down to 0 volts, it damage mAh capacity while it gets higher peaked voltage.
Peak voltage doesn't mean much, actually, I think the higher the IR the higher the peak voltage. Don't discharge IB cells down to zero, there is no benefit, and you risk cell reversal.
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Old 03-24-2006, 09:14 PM   #29
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so far ive got a 1o amp discharger looking to upgrade to a system thats good for gp and ib's so far looks like a ctx d or team wave lightning?
thinking about a 30 amp resistor rack just for at the end of race days nt sure
dont have much cash but it seems like ill have to fork out about $200us so not to keen.
opinions?
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