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Old 12-13-2005, 07:30 AM   #856
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ae racer, i think i got you a little confused.

discharging: you should discharge at a high amp rate down to .9volts per cell. this is to train the cells to what you normally race at.

dischargers: these things only discharge the pack down to a set voltage. There are tray type which discharge each cell individually and then there are pack types, these do the whole pack. the tray type are usually called discharger/equalizers from a marketing standpoint. example is the integy 0-30. this is a rapid discharge at 30 amps and you can think of it as an equalizer because it is bringing each cell down independant of the other. The problem with this for 3800 is that the low cut off is 0volts per cell. This is where it does most of it's equalizing. because it hold cells at 0v volt and wait for each cell to get to 0 volt. if you try to use this at .9volt, what you will see is if the pack is not a match pack and fairly new, the lights go out but some of the cells will be lower the .9, some will be higher then .9 and some will be .9. because 3 cells are on one knife switch and 3 are on another.

equalizing trays: these are general low amp dischage and do most of there work around their cut off. you can use this as a discharger, but then you are not training the cells to discharge at high amp rate as you race.

so the theory is to train your packs!

High discharge until the pack is "empty" (this is thought of as .9 for ib3800) and then to equalize the cells to .9v/cell so that each cell is at .9v for storage.

or if you are using one product, then: high discharge until .9 for storage and then back on the discharger/equalizer for 1-2 min before you charge, just to equalize the pack. I believe this brings the pack below .9volts per cell, but you are not keeping them there for any length of time.

if i have missed any part of this please correct me. This is just my understanding from all the reading
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Old 12-13-2005, 08:20 AM   #857
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theis

You pretty much got it right.From what I'm reading,I think the problem with the 0-30 is like you said it works around the "0" area for EQ'ing and the 38's don't seem to like that.This is where the Tekin is a better tray as far as EQ'ing the 38's goes, because it works around the .5 area.So when you discharge at 30 amps down to .09 you can store there and then when it's time to race you can throw the packs on the Tekin and EQ down to .5 and get a good even EQ without worrying about the packs being at "0" or somewhere inbetween,in other words "Not equalized"
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Old 12-13-2005, 09:10 AM   #858
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Quote:
Originally Posted by JayBee
Just FYI storing them on the Novak Smart thingie doesn't KEEP your cells equalized at ANY set voltage. Once each individual cell reaches the set voltage the light goes out and the voltage SLOWLY climbs back a bit. The NST doesn't HOLD the cells at that set voltage just takes them there and shuts off. I don't know much about the IB cells YET (I will be doing my own tests) but I do know that they don't like to be stored at 0volts like the GP33's and 37's; they're more tempermental.
You miss read my post. I never said leave them stored on the Novak. I said store them equalized and I recommended the Novak to do that. Your comment can be the same for all discharge and equalizer trays. We all know the cells will usually increase in voltage once they have been discharged but hopefully once all the cells are brought down to the same level, they'll all rise to the same level as well still being equalized.
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Old 12-13-2005, 09:14 AM   #859
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[QUOTE=AE Racer]Danny said that you should use a turbo 35 to discharge to .9 volts after a race day and disnt mention equalizing them, so apparently his method doesnt call for them to be equalized when they are stored.

So what is the purpose of the high amp tray that you discharge them with before charging? The goal of Danny's method is not to take them down to zero, so then why discharge them at all if it isnt really equalizing or anything? Why use a high amp tray is it just for speed in discharging or to simulate racing conditions?

I sent a bunch of questions to Danny in a pm, but Ill post them here and mabey someone else can help me out.
Would it be good enough if I discharged at 20 amps on my 16x5v6 after a race day? I race offroad so the actual amp draw might be similar, I generally run a 14x2 in buggy. Danny said earlier in the thread that before you charge them you should put them in a high amp discharge tray for 1-2 minutes. Since you arent taking the cells all the way to zero on the high amp tray, that wont equalize the cells, and since you dont equalize the cells when you take them down to .9 volts/cell, when are they getting equalized?

QUOTE]

If you re-read my post, my method is identical to SMC's with the exception that I equalize my cells.

Also re-reading my post will answer your question regarding equalizing, high amp trays and bringing the cells down to zero.
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Old 12-13-2005, 09:28 AM   #860
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Quote:
Originally Posted by theisgroup
ae racer, i think i got you a little confused.

discharging: you should discharge at a high amp rate down to .9volts per cell. this is to train the cells to what you normally race at.

dischargers: these things only discharge the pack down to a set voltage. There are tray type which discharge each cell individually and then there are pack types, these do the whole pack. the tray type are usually called discharger/equalizers from a marketing standpoint. example is the integy 0-30. this is a rapid discharge at 30 amps and you can think of it as an equalizer because it is bringing each cell down independant of the other. The problem with this for 3800 is that the low cut off is 0volts per cell. This is where it does most of it's equalizing. because it hold cells at 0v volt and wait for each cell to get to 0 volt. if you try to use this at .9volt, what you will see is if the pack is not a match pack and fairly new, the lights go out but some of the cells will be lower the .9, some will be higher then .9 and some will be .9. because 3 cells are on one knife switch and 3 are on another.

equalizing trays: these are general low amp dischage and do most of there work around their cut off. you can use this as a discharger, but then you are not training the cells to discharge at high amp rate as you race.

so the theory is to train your packs!

High discharge until the pack is "empty" (this is thought of as .9 for ib3800) and then to equalize the cells to .9v/cell so that each cell is at .9v for storage.

or if you are using one product, then: high discharge until .9 for storage and then back on the discharger/equalizer for 1-2 min before you charge, just to equalize the pack. I believe this brings the pack below .9volts per cell, but you are not keeping them there for any length of time.

if i have missed any part of this please correct me. This is just my understanding from all the reading

The problem is again the Integy 0-30 tray is NOT an equalizing tray. First of all, while is does drain or discharge each cell individually, it does not stop discharging the cells individually once their voltage reaches a certain point. It keeps discharging the cells. Because of the layout and function of the 0-30 discharger, if the lights go out for one cell you cannot stop the discharging of that cell without stopping the discharge of 2 others.

You can argure that when all the cells have been brought down to zero that they are equalized. But this is not a good argument becuase you cannot store the cells at zero volts. Storing the cells equalized is the only way to receive any benefit of equalizing the cells. So in effect you are not equalizing the cells with this method.

The purpose of equalizing to help further "match" or make the pack act as one big cell. Storing all the cells in a pack at the same voltage will hopefully allow all the cells in a pack to accept the same amount of charge but also help each cell so it gives out the same amount of engery at the same rate as the other 5 cells in the pack.

Also, as you state "zero" is not seen as 0.9 per cell. Zero is seen as zero. 0.9 per cells is seen as the lowest amount of energy you can saftely store in the packs without negatively effecting the performance of the cell.
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Old 12-13-2005, 10:30 AM   #861
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Quote:
Originally Posted by koabich
The problem is again the Integy 0-30 tray is NOT an equalizing tray. First of all, while is does drain or discharge each cell individually, it does not stop discharging the cells individually once their voltage reaches a certain point. It keeps discharging the cells. Because of the layout and function of the 0-30 discharger, if the lights go out for one cell you cannot stop the discharging of that cell without stopping the discharge of 2 others.

You can argure that when all the cells have been brought down to zero that they are equalized. But this is not a good argument becuase you cannot store the cells at zero volts. Storing the cells equalized is the only way to receive any benefit of equalizing the cells. So in effect you are not equalizing the cells with this method.

The purpose of equalizing to help further "match" or make the pack act as one big cell. Storing all the cells in a pack at the same voltage will hopefully allow all the cells in a pack to accept the same amount of charge but also help each cell so it gives out the same amount of engery at the same rate as the other 5 cells in the pack.

Also, as you state "zero" is not seen as 0.9 per cell. Zero is seen as zero. 0.9 per cells is seen as the lowest amount of energy you can saftely store in the packs without negatively effecting the performance of the cell.
i agree with you, but integy sells it as a discharger/equalizer. and the thing does not actually cut off at 0, meaning it does not just open a ciruit.. it continues to draw power out of the cell and then it has diode to keep the cell from reversing polarity. so it does actually equalize, but at 0volts.
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Old 12-13-2005, 11:01 AM   #862
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Quote:
Originally Posted by theisgroup
i agree with you, but integy sells it as a discharger/equalizer. and the thing does not actually cut off at 0, meaning it does not just open a ciruit.. it continues to draw power out of the cell and then it has diode to keep the cell from reversing polarity. so it does actually equalize, but at 0volts.
What good is equalizing cells down to zero amps if you cannot store the cells at zero amps? The hole point of equalizing is to train the cells. Keeping the cells equalized for 10 seconds will do absolutly nothing.

Besides, do you know how long it would take this tray or any tray to get cells down to zero amps? I am pretty sure that it would take days on the tray to get all the cells down to the exact same voltage. That's not practicle.

In case you cannot tell, I have a problem in calling the 0-30 an equalizing tray
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Old 12-13-2005, 11:04 AM   #863
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i agree
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Old 12-13-2005, 03:56 PM   #864
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If you discharge a pack down to 5.4 volts one cell could be a lot higher than
.90. I thought the idea was to get all the cells down to .90 on a tray, not zero. A Novak tray stops at .90 per cell and I am sure other trays do the same thing, I have trays that do that because I have checked with a volt meter after they were on the tray for days. I don't believe storing is the issue, it is to start the charge when all cells are at .90. That is why Danny wants us to put the pack on a tray before charging.

Right?
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Old 12-13-2005, 04:11 PM   #865
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Quote:
Originally Posted by Ted Flack
If you discharge a pack down to 5.4 volts one cell could be a lot higher than
.90. I thought the idea was to get all the cells down to .90 on a tray, not zero. A Novak tray stops at .90 per cell and I am sure other trays do the same thing, I have trays that do that because I have checked with a volt meter after they were on the tray for days. I don't believe storing is the issue, it is to start the charge when all cells are at .90. That is why Danny wants us to put the pack on a tray before charging.

Right?
It's easy to check the trays to see if they are IB safe. If you look at the bottom of the tray and see a diode in series with the resistor the tray will stop flowing current at at least 0.7v per cell (Higher if there is a small resistor before the diode).

It's funny but all the really old trays were like this and over the last 2 years the diodes started to get left off so the batts would get to 0.0v.
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Old 12-13-2005, 04:13 PM   #866
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Quote:
What voltage are you reffering to that the motor can't pull more than 11 amps?? I have stocks that pull 12-13 at 7 volts no load, and I run on high traction asphalt indoor touring, thats not a very big track (10 sec laps) I run 3800's and my motors rarely come off over 150 deg F. And my car is very fast. I have been experimenting with trimming the trailing edge (advancing the timing) with fairly good results. Seems the motor has a bit more grunt (due to reduced brush wrap) but still high RPM, so I was able to gear up 1 tooth. Car is super fast, and has better punch.
You are right... and I will not argue on your point!

I wrote my answer without reading it... IT WAS AN ERROR ON MY PART.

What I meant is that motors that pull over 11 AMPS at less than 4 volts USUALLY OVER SATURATE the magnetic field. AND I SAY USUALLY NOT ALWAYS!!!

hope this clears it.
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Old 12-13-2005, 04:15 PM   #867
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What we need is a tray that tells us what each cell is at.
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Old 12-13-2005, 04:44 PM   #868
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Quote:
Originally Posted by Hyper1
What we need is a tray that tells us what each cell is at.
MuchMore Racing is coming out with such a tray....
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Old 12-13-2005, 07:10 PM   #869
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I think Im just not good at explaining myself. I know what everything is and what it does. I was just saying that Danny's method doesnt involve real equalization at any point. A tray is never used to equalize the cells in his method. The 0-30 tray is used for 1-2 minutes, but that time probably isnt even getting the cells all the way down to zero volts so they arent being equalized.

The muchmore tray doesnt mention holding the cells at cutoff, so I assume that it doesnt, and thats pretty important, because otherwise the cells reach the cutoff voltage at different times and the equalizer breaks the circuit of a cell once it reaches cutoff. The cells that reached cutoff first will have more time to regenerate voltage than those that reached cutoff later, so they will have a higher voltage when you take the pack off of the tray so they cells arent really equalized.

The tekin tray and the team wave tray hold the cell at the cutoff voltage. The tekin does this by shutting off and turning back on when the cells voltage regenerates, and the team wave tray does this by lowering the discharge rate of each cell independently to stay at cutoff voltage, and continue discharging until the current has reached zero at the cutoff voltage. I dont have a great understanding of current so feel free to correct me, but I think the tekin tray will also take the current down to zero after it has taken the cell down again after it regenerates a number of times. I think that the team wave tray will probably take the cells' current to zero much faster though because it doesnt wait for the voltage to regenerate. The team wave says that it has completed equalization once the current of all cells has reached zero, and my guess is that the tekin tells you its done once all cells reach .5 volts, and the cells probably wont reach zero current unless you leave them on the tray for an extended period of time. This is why Im wondering if it would be worthwhile to get the team wave tray over the tekin.
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Old 12-13-2005, 07:14 PM   #870
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Quote:
Originally Posted by Hyper1
What we need is a tray that tells us what each cell is at.
Im pretty sure the team wave tray does this in volt meter mode. You can also charge a pack on it when it is in volt meter mode and monitor the voltage of each cell while charging.
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