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Old 10-12-2006, 11:10 AM   #16
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Could someone take a DPD apart and make picture of the internals? Just would like seeing how its made.
Iīm using the older Team Wave and in general itīs not bad but the connectors/ contact springs are not very good. Regarding this the DPD is the best in my opinion, just donīt know how they are doing the discharge circuit so a picture would be useful. Regarding the CTX I think this is overpriced. The discharging circuit seems a cheap solution, not that what I would expect for that money.
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Old 10-12-2006, 01:06 PM   #17
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The cool thing about the CTX-D is that when powered by a separate P/S, you can watch cell voltage as your pack charges.
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Old 10-12-2006, 08:07 PM   #18
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DODGE: IT does discharge each cell on its own. That is how i was able to take my 6 packs(36cells) Cycle them on the DPD and determine that if i shufled some cells around i could create 4 great packs and 2 practice packs instead of 6 so-so packs..

QUANTUM: I never said it was a turbo matcher i said it was a 120tray vs a 400 turbo matcher. In other words u get what u pay for!

I dont know for sure how it works but from what i can tell it pulls the pack down at 30amp pulse till one of the cells hits .9v(this is your weakest cell or at least your cell with least run time) And then switches to 5amp individual discharging for the rest of the cells. I dont see how its now not giving those remaining cells as deep a discharge. Like u said its a combo 5amp equilization tray with dyna pulse. I think that pulse action probably goes 30amp pack-5amp cells-30amp pack-5amp cells till the first cell hits .9v. That on/off allows the cells to breath between 30amp hits and the voltage likely comes up a bit.

YR4DUDE: I have not seen the display on my PDP say that its in 30 or 5 amp mode. I use pulse and internal and it only shows the runtime at the top and my 6cells and there voltages or done, it doest show any other info how did u see that 30 or 5 amp change over on yours what did the screen look like?


If anyone likes i can post an xcel sheet of what i found, wiht my packs. They where all integy low end 3800s.
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Old 10-12-2006, 08:27 PM   #19
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The DPD does not individually discharge each cell at 30A pulse, so the 5 other cells still have more in them at that instant (unless every cell hits .9v at the same time, but if that happens then you dont really need to equalize them do you?) and then it goes to 5A.
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Old 10-12-2006, 08:30 PM   #20
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Thats right its pulsing the whole pack at 30amps, when one of the cells reads .9v its switches to liniar 5amp for the remaining cells. They likely do this because it would cost a fortune to have 30amp pusle for 6 then 5 then 4 then 3,2,1. I can understand that. So whats the beef here?
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Old 10-12-2006, 11:15 PM   #21
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Quote:
Originally Posted by Joel Lagace
Thats right its pulsing the whole pack at 30amps, when one of the cells reads .9v its switches to liniar 5amp for the remaining cells. They likely do this because it would cost a fortune to have 30amp pusle for 6 then 5 then 4 then 3,2,1. I can understand that. So whats the beef here?
The Much More tray discharges each cell individually, both linear and pulse.

I think the beef most people have was the fact that the DPD was advertised so it seemed as though it would individually pulse discharge each cell, when in fact it only does the exact same thing as a Dynapulse.
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Old 10-13-2006, 12:05 AM   #22
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Quote:
Originally Posted by XrayFK
The Much More tray discharges each cell individually, both linear and pulse.

I think the beef most people have was the fact that the DPD was advertised so it seemed as though it would individually pulse discharge each cell, when in fact it only does the exact same thing as a Dynapulse.
Then in that case the numbers from the DPD don't mean anything.

How can time and capacity at 30A pulse be the same as 5A linear when they're using different voltages?

The fact that it is discharging my batteries quickly and conditioning them at the proper cut-off voltage makes it a good battery conditioning tool however the readout is useless if the numbers don't make any sense or can not be relied upon.
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Old 10-13-2006, 12:42 AM   #23
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Quote:
Originally Posted by YR4Dude
Then in that case the numbers from the DPD don't mean anything.

How can time and capacity at 30A pulse be the same as 5A linear when they're using different voltages?

The fact that it is discharging my batteries quickly and conditioning them at the proper cut-off voltage makes it a good battery conditioning tool however the readout is useless if the numbers don't make any sense or can not be relied upon.
In that case, for all the cells other than the first one, the data includes readings taken from the cell during a 5A linear discharge mixed in with the 30A pulse that cuts off once one cell hits .9v. Doesn't make the numbers useless, just need to know how those numbers are achieved.
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Old 10-13-2006, 04:13 AM   #24
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Quote:
Originally Posted by YR4Dude
Anyways this is the big question. If there wasn't a set of leads connected to every connection, how does it give me per cell voltage reading? Someone please educate me because I thought that if the cells are discharged and measured individually, there should be a separate lead for each battery contact. Instead, I found only certain contacts connected only.
If i guess this correctly, you will have 1 wire connected to the plus and one to the negative, the other wires will be connected to what is effectively the battery bar between each of the others cells. So, when the discharger wants to check the voltage of each cell it does it in series, swapping the polarity of the wires to suit the cell it wants to monitor.

Have a look at the diagram, to check the status of cell A, use wires 1 and 2, to check cell B use wires 2 and 3, to check cell C use wires 3 and 4, etc..

So, i think thats why they don't need 12 wires, 2 to each cell, the computer chip programming sorts out the polarities and works it all out???
Attached Thumbnails
Which one will u get? Trinity's new Discharger or MM CTX-D2-battery.jpg  
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Old 10-13-2006, 04:41 AM   #25
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How are the numbers useless. I find it crazy to here the complaining here, ITs quit simple, if it does cut off at the first sell why is that an issue? That first cell is obviously your weakest cell right??

Regardless the numbers are as usefull or useless and motor dyno numbers or should i say motor numbers from dynos such as muchmore,aps,integy and the other all in one no load dynos. The numbers are valid as they allow u to compare cells within a pack. just as running 3 motors on my aps allows me to make a somewhat informed decision of wich motor to use as my number one..

The data you get from the DPD is not transferable to a turbo charger or a much more or anything, its DPD numbers to compare to other DPD numbers of packs u own.

I have done internal runs vs external runs and you know what? The packs rate in the same order. My best pack is still my best pack when comparing data from the 2 modes. This says one thing its accurate enough to weed out bad packs or cells.

Check out the following intgy matche pack i cycled.... hardly a matched pack would u say? That one weak cell really makes the whole pack pay the price in numbers:
PACK P1 388 7.38 3280 14.9
P1*1 510 1.25 4296 1.7
P1*2 509.7 1.24 4293 2.3
P1*3 388 1.2 3279 2.6 sent to PACK 1
P1*4 466.8 1.22 3936 2.8
P1*5 468.4 1.21 3949 2.8
P1*6 518.9 1.24 4370 2.3

As u can see cell3 is the culprit with its low run time. Does it really matter that it switched to 5amp after cell 3 dumped? Not at all in the end the pack got its pulse discharge and its equilization and i discoverd the really weak cell.

Here was a pack that i left alone, and has been the top pack of the bunch no real weak cells here:

PACK 3 na na 425 7.31 3589 12.3
3*1 462.2 1.23 3899 1.8
3*2 425 1.22 3589 1.8
3*3 459.6 1.2 3878 2.4
3*4 466.7 1.2 3937 2
3*5 474.3 1.21 4000 1.9
3*6 470.2 1.22 3966 1.9


Anyway im sure the pissing match will continue, im just saying for he money and for what it does im happy with it, sure its not perfect if i could change anything this is what i would do to it:
-data screens would not auto scroll after cycle
-add dead short mode
-allow liniar 30amp with individual cell cut off allowing it to keep the 30amps running on remaining cells
-when in pulse mode i would like the display to tell me what its doing,30amp,5amp or 0amp?
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Old 10-13-2006, 04:43 AM   #26
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ps i beleive to hit your cut off voltage of .9 or what ever its much more accurate to do it at 5amp then it is at 30amp, at 30amp you always risk the chance of pulling down past the .9v cut off because its such a strong load. Again for the doh its not a bad unit
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Old 10-13-2006, 10:12 AM   #27
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Jake - wires were at 1 & 6 there was a 3rd set of wires somehere in between

Joel - your numbers were from the 5A linear. I was told the discharge time at that rate on individual cells does not equal to that of a pack discharged on a 0-30 discharger.

What I was hoping for was a 0-30 that cuts off at .9V while monitoring voltage and runtime of each individual cell.

Obviously thats not what I got. So will the Integy unit be the one I want?

Considering that they made the 0-30 I certainly hope so.
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Old 10-13-2006, 11:07 AM   #28
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taking my camera into the hobby shop today. I will pull it apart and take pictures. They will be on here tonight.

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Old 10-13-2006, 01:41 PM   #29
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Quote:
Originally Posted by YR4Dude
Joel - your numbers were from the 5A linear. I was told the discharge time at that rate on individual cells does not equal to that of a pack discharged on a 0-30 discharger.

How do u figuer that. Its pretty simple to set the unit up:
1)power on
2)select 2 for Pulse
3)select 1 for internal pack
4)select cut off
5)unit runs. In pulse mode as per the manual it have selected 30amp dyna pulse

I dont know what all the confusion is about.. Are u sure you have a DPD? LOL

Also you cannot compare numbers from PDP to the integy 0-30 as the integy does not display numbers. And if it did you cannot compare the 2 just as u cannot compare a robitronics dyno to fantom dyno numbers

Maybe im misuderstanding you??
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Old 10-13-2006, 05:02 PM   #30
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let me be clear about something. i don't think (and i don't think anyone here) is saying the dpd is a bad product. in fact, for the price and what it does, its a great purchase. i will probably end up getting it. but lets call a spade a spade...lets be clear about what it is and what it isn't.

what it does do is pulse discharges the pack until one cell hits 0.9v, then switches to equalize the pack discharging each cell individually at 5amps. lets call them phase 1 and phase 2.

during phase 1 (pulse discharge) you are reading the voltage for each cell AS IT IS BEING DISCHARGED IN A PACK. the voltage, duration of how quickly it drops would be different if being discharged individually. not a problem, just different.

when the first cell hits 0.9v, the rest of the cells have not been discharged as deeply so they begin to discharge at the lower rate with more current in them.

because of what happened during phase 1, each cell will again reach 0.9v at different rates during phase 2. will each cell be held at 0.9v or will the discharge simply stop at that point? if its the latter, then the voltage will rise up again.

note that i did not state what the outcome is for the pack or cell for these situations, simply that they occur.

compared to the muchmore tray, each cell is discharged individually to 0.9v, and then linearly discharged again to 0.9v individually. each cell gets the same treatment every time. consistency counts.

you can't say that about the trinity pack because the relative strengths of the cells will change. how much each cell gets discharged before another cell hits 0.9v may change.

the good thing about discharging as a pack, the weaker cell is still the weaker cell. i think its still better to give each cell the same consistent discharge every time which seems to keep the numbers good.

with the previous dynapulse you could ONLY dynapulse the pack, the cut off is 5.4v as a pack... well that doesn't protect against one cell going below 0.9v while others are above... its 5.4v for the whole pack! so the dpd is an improvement over that...

correct me where i may be wrong (its a friday after a long week!)

now i just have to figure out where the best place is to buy this damn thing...still cheaper than the much more
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