# using revolectrix cellpro powerlab 6 for charge/balance?



## TheSGC (Nov 15, 2007)

I have the PowerLab 6 and I configured it using my PC to change the different parameters. 

Which kind of cells are you using? 

The generic LiPo setting is for 3.7v cells, and the 40a discharge rate was designed for the A123 cells, assuming you are using a 24v lead acid battery as your power source.


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## Karter2 (Nov 17, 2011)

If it's anything like every lithium balance charger I have used, you have to tell it how many cells you are charging, then it will check if the voltage of the cells is within a"safe" range to start charging.
If you have cells that are too low (~<2 volts ?) then you may have to set it up as a simple "bulk" charger ...no balance leads connected...and lie to it as to how many cells you are trying to charge !


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## dtbaker (Jan 5, 2008)

TheSGC said:


> I have the PowerLab 6 and I configured it using my PC to change the different parameters.
> 
> Which kind of cells are you using?
> 
> The generic LiPo setting is for 3.7v cells, and the 40a discharge rate was designed for the A123 cells, assuming you are using a 24v lead acid battery as your power source.


I would like to charge/top-balance my 100ah CALB LiFePO4 (prismatic) cells individually. I am using a 12v-50amp power supply, so I should be able to get 400 watts thru the powerlab at 12v according to the spec sheet.

problem I am having is that I get the error 'bad cell count', and it doesn't start.

I am just doing 1 cell, and just using the two output wires, no FMA or balancing wires. So, I can't figure out how to tell it to just go with 1 cell at full blast.


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## rwaudio (May 22, 2008)

dtbaker said:


> I am attempting to charge/balance individual cells using a using revolectrix cellpro powerlab 6. The attraction is 40 amp rate and what looks like a good accurate variable end-of-charge voltage setting.
> 
> however, attempts today to use it have been frustrating. I have gotten thru the setup menus (I think) selecting 'generic LiPo' chemistry, setting max amps, end voltage, and 'charge only'. BUT.... it checks the cell voltage before starting, and gives an error about the cell count.
> 
> ...


You can get the manual here:
http://www.revolectrix.com/support_docs/item_1380.pdf

If you are trying to charge/discharge above a certain rate (like 10A or something) you need to use the balance wires even if it's a single cell. That way it can measure the cell voltage without having to account for the drop in the very small stock wires. I would recommend 8awg or dual 10awg for 40A use. The stock wires get VERY hot at 40A and I wouldn't consider it safe for long term use.

I basically cut the stock wires in half, soldered on another banana plug, removed the fuse and doubled them up so it had dual 10awg to some ring terminals that I connected to my CALB's.


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## dtbaker (Jan 5, 2008)

rwaudio said:


> You can get the manual here:
> http://www.revolectrix.com/support_docs/item_1380.pdf


fab, got it, read it.....



rwaudio said:


> If you are trying to charge/discharge above a certain rate (like 10A or something) you need to use the balance wires even if it's a single cell.


aha! this might be it, I set the charge to 20A or 30A since that is the whole reason to use this rather than my slow 10amp max power supply. well, that and the auto (accurate) end-of-charge. I will try setting the rate back down to 10amps and see if it faults still.

I did not get balance wires with my unit, wondering if I might find them in local radio shack, or have to order them from revoletrix?! drag.



rwaudio said:


> I would recommend 8awg or dual 10awg for 40A use. The stock wires get VERY hot at 40A and I wouldn't consider it safe for long term use.


I did make some up w 10AGW....


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## rwaudio (May 22, 2008)

dtbaker said:


> fab, got it, read it.....
> 
> 
> aha! this might be it, I set the charge to 20A or 30A since that is the whole reason to use this rather than my slow 10amp max power supply. well, that and the auto (accurate) end-of-charge. I will try setting the rate back down to 10amps and see if it faults still.
> ...


You only need to connect two wires to the balance connector, you might be able to rig something up. The proper connector is JST-PA, they might be available from a hobby shop, but likely not radio shack.

There are two different wiring modes for balancing, check the manual to make sure you use the same wiring type as the charger is set to. Make sure your input wiring from the power supply is SOLID, the charger can give random errors and flake out for no apparent reason if the connections aren't perfect, more so on regen discharging but also on charging.


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## dtbaker (Jan 5, 2008)

rwaudio said:


> You only need to connect two wires to the balance connector, you might be able to rig something up. The proper connector is JST-PA, they might be available from a hobby shop, but likely not radio shack.



page 12 shows NO balance wire connection used if pack is 'unbalanced' (i.e. one cell) no mention of amp limit. I won't get a chance to verify this till tomorrow earliest....


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## rwaudio (May 22, 2008)

The other thing be careful of is starting with the correct preset. One of the A123 High Power presets works best with LiFePO4.


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## dtbaker (Jan 5, 2008)

dtbaker said:


> I am attempting to charge/balance individual cells using a using revolectrix cellpro powerlab 6. The attraction is 40 amp rate and what looks like a good accurate variable end-of-charge voltage setting.
> 
> however, attempts today to use it have been frustrating. I have gotten thru the setup menus (I think) selecting 'generic LiPo' chemistry, setting max amps, end voltage, and 'charge only'. BUT.... it checks the cell voltage before starting, and gives an error about the cell count.
> 
> ...


initial reply I got from revolectrix indicates a couple key things I'll share for the group....
- it probably will not initiate a charge cycle if cell voltage is below 2.5v so a power supply or a 'dumb' charger will be needed to get the cells up to at least 2.75v before finishing w the cellpro

- best preset to start with is A123 non-balance preset and you are still limited as far as the maximum output of 20 amps without the node wire installed. If a node wire is used, max can be up to 40.

..... I am using a power supply right now, going thru each cell with an hour or so charge, which seems to bring them back to 3v or so even with my weenie mastech (10amp max) power supply. then I will go thru them all with the cellpro to charge and top-balance to 3.700


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## dtbaker (Jan 5, 2008)

still having problems getting a charge cycle to start.... ;(

I set type to unbalanced, 1s A123. max amp=9.75, finish voltage 3.650, 0 cycle charge only. It thinks for a while, and then beeps that supply voltage is too low.

supply v cutoff is 10v, and I am using a power supply, not battery, so what gives!? I checked output voltage of power supply, it's not 12, it's only 11.2, but that should be ok. I twiddled voltage adjustment screw, but saw no change in output voltage.... perhaps power supply is faulty?!

getting really frustrated....


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## rwaudio (May 22, 2008)

dtbaker said:


> still having problems getting a charge cycle to start.... ;(
> 
> I set type to unbalanced, 1s A123. max amp=9.75, finish voltage 3.650, 0 cycle charge only. It thinks for a while, and then beeps that supply voltage is too low.
> 
> ...


Make sure the power supply leads are very short and securely connected. I had this issue many times with a battery as the supply. If you have a spare meter throw it on the PL6 input terminals to see what the voltage drops to when it starts charging. Under load it may drop the power supply voltage down to 10 (or what it reads as 10v if you have long wires or a poor connection, or faulty power supply). 

Do you have a spare 12v lead acid battery and battery charger? Or just string together some of the CALB's to make a power supply for testing to get you started (don't over discharge them), if you can confirm the PL6 works fine and it's just your power supply you can replace the appropriate item.


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## dtbaker (Jan 5, 2008)

rwaudio said:


> Make sure the power supply leads are very short and securely connected. I had this issue many times with a battery as the supply. If you have a spare meter throw it on the PL6 input terminals to see what the voltage drops to when it starts charging. Under load it may drop the power supply voltage down to 10 (or what it reads as 10v if you have long wires or a poor connection, or faulty power supply).
> 
> Do you have a spare 12v lead acid battery and battery charger? Or just string together some of the CALB's to make a power supply for testing to get you started (don't over discharge them), if you can confirm the PL6 works fine and it's just your power supply you can replace the appropriate item.



I took the cheap 12v power supply out of the equation, and tried the Mastech (which puts out up to 30vDC at 10amps).
YAY, the cellpro is finally charging at 20 amps!

will order a connector node and see if I can get up to 40 amps.


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## dtbaker (Jan 5, 2008)

Limping along at 20amps..... haven't ordered the node connector yet. At 20 amps things are working, but takes long enough that the unit 'times out' while filling a 100ah cell from near-dead. Not aweful, I just re-start it and it finishes up the charge.


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## rwaudio (May 22, 2008)

dtbaker said:


> Limping along at 20amps..... haven't ordered the node connector yet. At 20 amps things are working, but takes long enough that the unit 'times out' while filling a 100ah cell from near-dead. Not aweful, I just re-start it and it finishes up the charge.


You can change the timeouts with the CCS software, (it's just a setting within the preset) I'm not sure if you can do it directly on the unit. 

If you have to order the node connector you may also consider the USB adapter if you don't already have it.


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## dtbaker (Jan 5, 2008)

ok, I completed a pass thru all cells using just the large charge wires.... and just got a generic 'node wire connector' and the computer USB interface so I can set up presets for a final pass to top balance accurately.

I was planning to just jumper the node wire 1,9 (red/blk) to the large charge wires rather than run a second set of clips to the cell I am charging. Is there a problem with doing this? will the voltage be accurate and handle the end-of-charge consistently this way, or should I runthe node wires all the way to the cell as well with a second set of clips?

I'm asking because I just checked the voltage with a voltmeter right next to the output of the cellog6 (4.000v), then down on the charge clips (3.75ish), then down off the clips, but on the bus strap connected to the cell I was charging (3.620).... this confused me to see different voltages along the charge wires at different points between the charger and cell itself. This made me wonder if I need to have the cell node wires clipped in all the way down at the cell terminals rather than up right where the charge wires come out.


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## dtbaker (Jan 5, 2008)

so..... I have completed first pass thru all cells using just the main charge wires on the cellpro. I also ordered and got the 'node wire' connector and the USB computer connector so I can fine-tune my final pass at top-balancing before trying a normal series charge and final manual top balance check.

I charged all cells to 3.60, drove around the block, and will begin taking another pass thru all cells using the node wires for as accurate a charge as possible. Then,

drive around the block (about -1AH), and do a series charge, checking all voltages just after charge ends, and manually drain a little off any cells showing more than .02v above average to get a nice top balance....

My QUESTION, is whether jumpering the node wires as shown here will yeild as accurate results as if I ran a separate set all the way to the cell terminal in conjuction with the charge cables.


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## dtbaker (Jan 5, 2008)

...just a followup on what I'm doing for the second pass at charge/top-balancing.

I'm using a a123 preset, and altered a few settings to get the quickest charge I can as I go from cell to cell. I was able to tell the cellpro6 to not do a discharge cycle, set finish voltage to 3.675, and terminate without a CV stage at all (i.e. not use c/10 or a manual amp cutoff). I did this in part because I was not able to set the C value to 100ah; also because all I am trying to do is get an accurate top-balance, not a fully saturated charge.... so a CV stage really isn't needed.

I think this is going to work pretty well.... I drove the car around the block to knock down the pack about 1ah, and its taking just a couple minutes per cell for the cellpro to top-balance to 3.675 and end the charge as I move thru the pack.


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## rwaudio (May 22, 2008)

dtbaker said:


> so..... I have completed first pass thru all cells using just the main charge wires on the cellpro. I also ordered and got the 'node wire' connector and the USB computer connector so I can fine-tune my final pass at top-balancing before trying a normal series charge and final manual top balance check.
> 
> I charged all cells to 3.60, drove around the block, and will begin taking another pass thru all cells using the node wires for as accurate a charge as possible. Then,
> 
> ...


The whole point of the node wires is to compensate for voltage drop in the wires at high currents. The way you have it hooked up is bypassing this, the internal voltage sense wires would be hooked up to the banana jacks just on the inside of the case, you are basically doing the same thing just on the outside of the case.

This image is a good example (meant for 4 wire resistance measurement) but it's the same goal, measure accurate voltage without the current messing up the reading.










Connect the node wires directly to the cell terminals and make sure it's a good connection, ( and more importantly do it the same for every cell. To exaggerate the example if you charged one cell with the node wires hooked up the way you have them now, and charged another cell with the node wires connected to the cell terminals they would be charged differently, now the difference would be much lower when connected to t he cell terminals however it does make a difference, also internal resistance measurements will be all over the map if you don't connect the cells exactly the same.

Good luck, once you get past all these little picky things with the PowerLab it's a pretty good device for the money.
To get better I had to step up to a pair of Agilent 50A power supplys and a Maynuo 60A electronic load. Now the results using this are much more consistent and I never have the "errors" the Powerlab will produce for no apparent reason as you use it. The power supply won't terminate at c/20, so that required external current monitoring and a relay, fairly easy and much more reliable and will terminate at an exact current vs the Powerlab which doesn't really seem to terminate consistently or anywhere near the set current. IE 100Ah cell at c/20 should be 5A, I'd put money on the Powerlab not terminating anywhere near 5A.


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## dtbaker (Jan 5, 2008)

rwaudio said:


> You can change the timeouts with the CCS software, (it's just a setting within the preset) I'm not sure if you can do it directly on the unit.
> 
> If you have to order the node connector you may also consider the USB adapter if you don't already have it.



I cannot set the cellpro6 to deliver more than 20amps using preset 11, which is for a123 default. I also cannot set charge timeout for more than 4 hours.... This will be fine for my intended use as a fairly quick top balance system though as it takes only 10-15 minutes per cell if they are 'near full'. 

If I were wanting to do lots of cell packs, from factory 50% DOD for initial charge, I would consider getting a Elcon1500 or something like that preset to do a 3.65v charge and get a full 1500 watts dumping in, or do a series charge with main charger and babysit to turn it off as soon as pack voltage started to rise, and finish with the revolectrix cell by cell to get the initial top-balance.


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## dtbaker (Jan 5, 2008)

rwaudio said:


> The whole point of the node wires is to compensate for voltage drop in the wires at high currents.... the Powerlab which doesn't really seem to terminate consistently or anywhere near the set current. IE 100Ah cell at c/20 should be 5A, I'd put money on the Powerlab not terminating anywhere near 5A.



ahhhh, now this is all making more 'sense', 

what I have done this am before starting final pass is set the termination to not use C/10, or a manual setting even, but to just terminate when it hits CV.

I am thinking that in this way, the absolute value doesn't matter all that much as long as I get a consistent termination voltage (for a consistant top-balance). Thanks for the tip on same 'clamp position' though, as that may well affect the voltage drop, etc.

I guess it would be MOST accurate to run the sense wires completely separately from charge wires, terminate in their own clips, and clip to the connector straps a little away from the charge clamps. But, I'm looking for consistent more than absolute accuracy for a good balance....

THANKS for this explanation.... I was freaking out measuring different voltages at different points with an external voltmeter. 


hhhhmmmmmm, and now I am thinking that since the voltage 'seen' by the node wires near the output is a little higher than at the battery terminals I'd probably be safe in setting the end voltage a little higher to get a more accurate end as the curve is a little steeper.... say 3.750 perhaps next time. ?!


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## rwaudio (May 22, 2008)

dtbaker said:


> ahhhh, now this is all making more 'sense',
> 
> what I have done this am before starting final pass is set the termination to not use C/10, or a manual setting even, but to just terminate when it hits CV.
> 
> ...


Glad you're getting there, the PowerLab is by no means plug and play, but it is quite powerful once you get the hang of it.

I don't have my PowerLab handy, is preset 11 one of the High Power A123 presets? The "normal" ones do have a current limit. You want to start with the A123 High power or high current (don't remember how they phrase it).

If that doesn't work try loading my old preset what many of us used for A123 20Ah testing to get comparable results.
http://www.diyelectriccar.com/forums/showpost.php?p=295476&postcount=18

You will need to tweak it since it's set to charge then discharge, but it does 38A. (I found 38A more reliable than 40A, for some reason I got more errors using 40A)


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