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Old 02-21-2006, 07:01 PM   #1
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Default A quick dead shorting question

what does it mean to dead short? Does it mean to short the battery by connecting the positive side to the negative side? Or does it simply mean to discharge the battery until they are all down to zero volt?

I have the Integy 6s discharger and the Integy 030 discharger. They both discharge the pack down to zero volts. If I leave my batteries in the discharger until they are all down to Zero, does that mean I am dead shorting my batteries? Or do I have to connect the positive side of the battery to the negative side in order to dead short them?
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Old 02-21-2006, 07:03 PM   #2
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discharge down to zero volts.

Don't "short" the battery leads. Ouch! You'll start a fire
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Old 02-21-2006, 07:09 PM   #3
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People continue to mix up these terms. Equalizing your cells is discharging them all down to the same voltage, regardless of what that voltage is. So discharging them all to zero is just that, discharging them to zero. Dead shorting is where you physically short out the pack, by connecting the positive end back to the negative end of the pack. Dead shorting will give you a slight increase in voltage and lower i/r, at the cost of a good amount of runtime (which you can never recover). If you do, only dead short your packs once you discharge them so there isn't much voltage in them. Also, don't deadshort IB cells.
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Old 02-21-2006, 07:11 PM   #4
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Thanks, I was thinking about the same thing. Here is also what I got from pro-match racing website:

"There are two ways to dead short a pack. Solder a wire from the positive end tab to the negative end tab which shorts out all of the cells in series.

The other is to short out each cell individually. That is to short the positive to the negative of each cell in the pack. This short is what is referred to as shorting in parallel."
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Old 02-21-2006, 07:32 PM   #5
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What are the advantages and disadvantages of dead shorting a cell or a pack?
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Old 02-21-2006, 07:36 PM   #6
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Quote:
Originally Posted by macgyver1432000
What are the advantages and disadvantages of dead shorting a cell or a pack?
Dead shorting will give you a slight increase in voltage and lower i/r, at the cost of a good amount of runtime (which you can never recover).
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Old 02-21-2006, 07:57 PM   #7
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Is it okay to dead short GP3700 cells?

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Old 02-21-2006, 09:23 PM   #8
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Just to clarify, you only solder in the short after you have discharged and equilized the cells down to zero volts or very close to that. Using the novak smart tray in DEAD SHORT mode is very safe way to do that. Solder the wire in while it still in the tray and then remove.
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Old 02-21-2006, 11:50 PM   #9
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Quote:
Originally Posted by trf_racer
Is it okay to dead short GP3700 cells?

Thanks
Yes you can, is it recomended no. I did it to mine, they are fine.
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Old 02-22-2006, 01:39 AM   #10
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Default Dead Shorting Batts

Is it ok if I dead short my Tamya 1700mAH stick packs and my GP3300mAH packs? How long before I remove the wires connecting the positive & negative terminals during dead shorting? May I know the correct procedure?
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Old 02-22-2006, 11:40 AM   #11
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I stopped deadshorting at 3000's. I don't short my 3300s and have read info from SMC, Express, Fantom, Associated not to ever dead short the IB 3800s.

Ask yourself why you should dead short. Deadshorting a stick pack - what the heck for? It's a stick pack - you're not going to see any improvement anyway. As for your 3300s, try it if you want, but dead shorting does kill the life of your cells. You might as well give it a shot and see if you notice any improvement. Then, after you have killed your cells, go buy an IB 3800 cell and go faster than you ever have in your life! Maybe even skip over that and go right to the IB 4400 cell and really crap your pants.
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Old 02-22-2006, 11:54 AM   #12
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I got some SMC high end 3300 packs i got about 3 years ago. I ran them for a year and then due to becoming a father i stopped racing... My packs got very little use in the last 2 year i ran them in the summer for some offroad racing. But maybe 20 races max in 2 years. This spring i started up bi-weekly racing touring cars again and decided about a month or so ago to dead short them as i did not have the $$ for new cells. They felt kind of soft untill i started dead shorting, now its like i have put new life into them, charge times are up and they feel fairly punchy now. I thought they where write off but i think i may still be racing with them. But im still grabbing a pair for IB3800s just in case
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Old 02-22-2006, 12:17 PM   #13
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How long do you dead short the cells for?

Do you just simply hook up a wire between the positive side and the negative side of your pack?
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Old 02-22-2006, 12:32 PM   #14
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i 20amp them, tray with novak smart tray on DEAD short mode, solder wire from pos to neg after tray inicates dead short. Then remove them till next race day. Wich for me is 2 weeks, then remove the wire before charging..

FYI: Not all chargers will be able to start charging your dead shorted packs even with lockout, what i have is the reedy quasar pro and i set the trickle charge function and i find after 30-60 seconds on trickle both the reedy and my aps charger will charge them. Other wise they detect dead or shorted leads(0volts)
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Old 03-15-2013, 05:28 AM   #15
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A dead short is a connection with zero/near-zero resistance.

It may be applied deliberately in order to perform tests, or, more usually, as the result of a catastrophic failure in some part/component.


"The positive and negative voltage lines are tied together - OR" - both lines of an a.c. supply are connected together.

"the positive line is shunted to ground with voltage applied" - OR - the negative line is shunted to ground, etc etc.
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