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Old 05-07-2007, 12:37 AM   #1
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Default IB4200 matched 20amp or 35amp discharge?

I have noticed that some cells like intergy are matched to discharge at 20amp and have 700+ sec run times and some like harris RC and SMC are matched at 35amp and have run times of 400+ secs. the 20a cells seem to be about $20 cheaper a set (which is $80 saving when buying 4 sets)


Which is better? I will be using my mamba max 7700 most of the time so needing extra power is not an issue... but when i run a CO27 stock for stock racing will i see a difference? or would the 35a packs make the system run happier? ie heat issues etc.

Cheers,

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Old 05-07-2007, 12:50 AM   #2
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35 amp
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Old 05-07-2007, 12:51 AM   #3
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I would imagine that the higher amperage batteries wouldn't get as hot
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Old 05-07-2007, 02:33 AM   #4
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I'd get the 35 Amp ones the will be higher in quality and less likely to fail.
35 amp matching weeds out the a lot of the bad cells where as the could slip past at 20 Amp matching due to the less load.

Just remember these 4200 are touchy and can still fail if mistreated.
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Old 05-07-2007, 02:58 AM   #5
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its a no brainer if you can afford the 35amp packs
The 20 amp packs are good for messing around and if you tight on a budget but not if you are a competitive driver/racer.
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Old 05-07-2007, 10:30 AM   #6
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Quote:
Originally Posted by Phroz
I have noticed that some cells like intergy are matched to discharge at 20amp and have 700+ sec run times and some like harris RC and SMC are matched at 35amp and have run times of 400+ secs. the 20a cells seem to be about $20 cheaper a set (which is $80 saving when buying 4 sets)


Which is better? I will be using my mamba max 7700 most of the time so needing extra power is not an issue... but when i run a CO27 stock for stock racing will i see a difference? or would the 35a packs make the system run happier? ie heat issues etc.

Cheers,

Ben.
If you are racing, the 35 amp.
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Old 05-07-2007, 11:20 AM   #7
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Quote:
Originally Posted by Tsquare
If you are racing, the 35 amp.
It depends when are you going to discharge @ 35A : When battery is full charge, or half discharge.

Discharging IB4200 @ 35A at full charge = Your cells will be naked at the end of discharging period, or end up with damage cells, or worse, your Turbo GFX is burned. I suggest 20A for battery cycling & full charged battery, 25A max for discharging after use battery ( I mean after 5 min mains / finals for low turn modified motors ).
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Old 05-08-2007, 01:33 AM   #8
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Well i do race but its not super competitive.. Its only a small club and its mostly for fun.

Alot of the guys dont even run matched cells, though a few run IB4200. So would i be correct to think that a pack matched at 20a is still going to be better than a non matched pack?
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Old 05-08-2007, 02:28 AM   #9
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Matched packs are going to be better no matter what,most people cycle their packs at 30 amps,even though the matching is done at 35 (soon to be 40) it's just easier on the packs and your equipment.
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Old 05-15-2007, 07:09 AM   #10
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Quote from an Intergy tech

"Thank you for your e-mail inquiry. As you probably know already, high heat can easily damage Ni-MH cells. We don't use 35A rate for discharge because the amount of heat generated from machine cycling these cell can cause internal cell damage. We've performed test and results show drastic reduction in runtime/performance after these cells are cycled at 35A rate. However, many matchers are still using 35A and claim that high current can screen out better cells. Now, a lot of them are struggling with large number of cell failure especially on IB4200. Our 20A matching process still produces good match and also offer a much better cell reliability in the long run."

What do you guys think??

Last edited by Phroz; 05-16-2007 at 02:51 PM.
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