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Discussion Starter · #1 ·
Is the tray cutoff voltage really that big a deal with todays 4200's ??

I've used a Tekin for a couple years without noticing any problems.

Some specs -------

integy 0-30 ---lights go out around .25 volt and goes to 0.0 if left there

Tekin batt doctor --- lights out at .70 to .80 and stops at .50 volts

Novak SE tray --- adjustible from .10 to 1.20 stopping voltage

Trinity D 90 --- stops at .90 volts

TRINITY DPD ---- adj from .10 to 1.00 volts

Any flat line tray --- goes to 0.0 if left long enough


Any proven data vs. just personnal preference ???
 

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NCFRC said:
Is the tray cutoff voltage really that big a deal with todays 4200's ??

I've used a Tekin for a couple years without noticing any problems.

Some specs -------

integy 0-30 ---lights go out around .25 volt and goes to 0.0 if left there

Tekin batt doctor --- lights out at .70 to .80 and stops at .50 volts

Novak SE tray --- adjustible from .10 to 1.20 stopping voltage

Trinity D 90 --- stops at .90 volts

TRINITY DPD ---- adj from .10 to 1.00 volts

Any flat line tray --- goes to 0.0 if left long enough


Any proven data vs. just personnal preference ???
Just a correction Novak SE will actually go to 0.0 volts
I use .9 per cell seems to work ok, I have noticed cells starting to vent lately after charging though, I heard some people say to use 1.0 volts i think I may try that
 

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Discussion Starter · #3 ·
I wouldn't blame the venting on any tray .

IB has a serious problem with that and you'll find some matchers right now that have switched to the EP cell , even though lower voltage , because of this problem .
 

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The new batch of IB's that just came out last week are not venting like the last few batches. Still good voltage, just .1 to .2 higer IR. I use the DPD, and cutoff at 1v.

Joel White
 

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Racin Steve said:
No it doesn't. The load is taken off the cell.

Steve.
DPD is also a pain because once one cell drops to .9 the thing takes a VERY long time to discharge... For example when discharging using the 30 amp pulse, it will discharge for awhile, once a cell drops to .9(or the desired cutoff) the charger drops to a low discharge rate... Not sure what the rate is but its slow usually lol...
 

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Discussion Starter · #8 ·
jeffbhhs said:
DPD is also a pain because once one cell drops to .9 the thing takes a VERY long time to discharge... For example when discharging using the 30 amp pulse, it will discharge for awhile, once a cell drops to .9(or the desired cutoff) the charger drops to a low discharge rate... Not sure what the rate is but its slow usually lol...
I thought this is what alot of racers complained about ,,, that when one cell hits the cutoff point it releases the load and bounces back up .

I think it should hold it their untill all the cells hit the cutoff or like the new Novak where it holds them at the cutoff untill removed.
 

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NCFRC said:
I thought this is what alot of racers complained about ,,, that when one cell hits the cutoff point it releases the load and bounces back up .

I think it should hold it their untill all the cells hit the cutoff or like the new Novak where it holds them at the cutoff untill removed.
How do you think the Novak tray or any other keeps the voltage at a hold point? It monitors the voltage and discharges more, so what’s happening is that the cell is constantly going form discharge to rest, discharge to rest over and over again. So that the cell your holding at a given voltage will be actually have less energy being stored in it when the last cell hits the discharge cutoff. So by holding cells at a given voltage less then the rest (no load voltage) is causing an imbalance in the pack. IMO
 

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Discussion Starter · #12 ·
IMOP ------ When a discharger releases the load when the first cell hits the cutoff ,, then its NOT an equalizing discharger.
Even Trinity with their DPD doesn't say it equalizes.

You might as well use your turbo 30 and just discharge to .90 per cell , thats all your really getting.
 

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NCFRC said:
IMOP ------ When a discharger releases the load when the first cell hits the cutoff ,, then its NOT an equalizing discharger.
Even Trinity with their DPD doesn't say it equalizes.

You might as well use your turbo 30 and just discharge to .90 per cell , thats all your really getting.
When a cell is being discharge and hit a set voltage there is the equalizing point. if you continue taking energy form it at a rate that isn't controlled in any way. How can you see that as being equal. The last cell that reaches the cutoff point is the only one you know how much energy is still left in the cell. the others have less then the hold votage because you kept on discharging them after the cutoff.
 

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MIKE VALENTINE said:
When a cell is being discharge and hit a set voltage there is the equalizing point. if you continue taking energy form it at a rate that isn't controlled in any way. How can you see that as being equal. The last cell that reaches the cutoff point is the only one you know how much energy is still left in the cell. the others have less then the hold votage because you kept on discharging them after the cutoff.
If the others kept bouncing up and the Novak equalizer keeps them at the "correct" voltage, how is this going to have less voltage than the last cell that reaches the cutoff? :confused:
 

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If the others kept bouncing up and the Novak equalizer keeps them at the "correct" voltage, how is this going to have less voltage than the last cell that reaches the cutoff?
The Novak discharge tray doesn't keep anything at the right voltage it just turns back on when the cell voltage bounces back up. Think about it this way if you discharge your pack on your GFX or whatever and you keep hitting start over and over again a couple seconds after the pack finishes. That is what the trays with a hold feature do. With the exception of the new "Battery Nurse" Tekin will be coming out with. It actually does hold your packs at a given voltage.

IMOP ------ When a discharger releases the load when the first cell hits the cutoff ,, then its NOT an equalizing discharger.
Even Trinity with their DPD doesn't say it equalizes.

You might as well use your turbo 30 and just discharge to .90 per cell , thats all your really getting.
Yes, the trays are different than simply using a GFX, even if the hold feature is not on. The tray individually takes each cell to 0.90 (or whatever) and indivudually turns off the loads on each cell when each cell reaches the cut off.
 

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pmsimkins said:
The Novak discharge tray doesn't keep anything at the right voltage it just turns back on when the cell voltage bounces back up. Think about it this way if you discharge your pack on your GFX or whatever and you keep hitting start over and over again a couple seconds after the pack finishes. That is what the trays with a hold feature do. With the exception of the new "Battery Nurse" Tekin will be coming out with. It actually does hold your packs at a given voltage.
So "in effect" it is keeping the cells "at or near" the .90 cutoff you set it too so when each light is blinking they should all be at or close to the cutoff, correct? The example with the GFX isn't really much of an example as you are discharging the entire pack until the cutoff so individual cells might be WAY different for the discharge (one cell .70 and another 1.0 as an example). The Tekin tray itself holds the cells at a given voltage it is just "to low" by todays NiMH standards from what most matchers say.
 

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Discussion Starter · #17 · (Edited)
QUOTE -------''The Novak discharge tray doesn't keep anything at the right voltage it just turns back on when the cell voltage bounces back up. Think about it this way if you discharge your pack on your GFX or whatever and you keep hitting start over and over again a couple seconds after the pack finishes. That is what the trays with a hold feature do. With the exception of the new "Battery Nurse" Tekin will be coming out with. It actually does hold your packs at a given voltage.''

I realize I'm a very picky consumer but your correct ,, I had a chance to try the new SE Novak and really not impressed ,,, The voltage hold funtion is real houky as it acts like a mosfet turning on and off ,,, if you put a voltmeter on it when set at .90 , it keeps jumping from .85to 1.00 as it turns on and off ??
I expected it to HOLD the cell at .90 steadily ! My old trusty , dusty Tekin at lights out , holds the cell at .78 and then slowly brings to .55 if I leave overnight and all cells are at that voltage.

I left a pack in the Novak overnight set at .90 hold and one cell was .22 and the other three were at 1.10 + ???? I measured across the pos and neg of the pack while in the tray and it measured 3.58 ??? pretty close to the .90 per cell , but at least this one didn't work that way.

I'll buy another Tekin as I've seen no noticable runtime difference even if you do leave them in overnight .
 

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Discussion Starter · #19 ·
NCFRC said:
QUOTE -------''The Novak discharge tray doesn't keep anything at the right voltage it just turns back on when the cell voltage bounces back up. Think about it this way if you discharge your pack on your GFX or whatever and you keep hitting start over and over again a couple seconds after the pack finishes. That is what the trays with a hold feature do. With the exception of the new "Battery Nurse" Tekin will be coming out with. It actually does hold your packs at a given voltage.''

I realize I'm a very picky consumer but your correct ,, I had a chance to try the new SE Novak and really not impressed ,,, The voltage hold funtion is real houky as it acts like a mosfet turning on and off ,,, if you put a voltmeter on it when set at .90 , it keeps jumping from .85to 1.00 as it turns on and off ??
I expected it to HOLD the cell at .90 steadily ! My old trusty , dusty Tekin at lights out , holds the cell at .78 and then slowly brings to .55 if I leave overnight and all cells are at that voltage.

I left a pack in the Novak overnight set at .90 hold and one cell was .22 and the other three were at 1.10 + ???? I measured across the pos and neg of the pack while in the tray and it measured 3.58 ??? pretty close to the .90 per cell , but at least this one didn't work that way.

I'll buy another Tekin as I've seen no noticable runtime difference even if you do leave them in overnight .

I'll correct myself ,,,,, Just don't leave in tray overnight in Hold mode.

The one cell probably self discharged. OH Well :wave:
 
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