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Old 03-03-2012, 08:05 AM   #147 (permalink)
IamIan
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Quote:
Originally Posted by eq1 View Post
Only thing that'd bug me about this is that you'd have to remove the sticks from the pack and remove the shrink wrap, which adds some work and time (16 of the 20 sticks just pull out, 4 of them have extra wires/thermistors attached, which you'd have to remove, too)... Plus, I'm merely assuming that you can access the connection points between each cell - without damaging the stick.
Due to the outer metal wall of a D cell being electrically the same as the bottom - terminal ... any connection to that is the same as connecting to the bottom... so... connect to the - stick terminal ( Hex shape if stick is out of pack ) the + of that same cell is the outside metal shell of the next cell.

The side effect of the above is that the stick does not have to be taken apart in order to gain electrical access to each individual cell ... you only need a point of electrical contact sufficient for your intended current level ... At one point I choose to do that with a slight modification to one of those round camps that tightens down in a circle as you turn a screw , available at all hardware stores.

Quote:
Originally Posted by eq1 View Post
How many sticks could you do without removing anything, treating them as a 6-cell unit (i.e. not a few sticks in series or parallel)?
For basic battery diagnosis and balancing I recommend this method as a major labor saver even if you are only doing one stick at a time ... leave them in the pack and just connect to the ends.

Under these conditions the PL8 manual only shows one 6 cell stick at a time would be supported ... at up to 20 Amp Rates per PL8.

There might be a loop hole I have not yet confirmed ... that could still allow up to 3 sticks at a time through the balancing port per PL8... But I have not confirmed that yet... and it is not a setup shown in the Manual.

Even without series connections or parallel connections only connecting to one stick per PL8 ... in the 'expansion' or master/slave mode ... with up to 15 slave PL8s to 1 master PL8 ... you could do 15 such sticks at a time ... each at 20 Amps... all into 1 USB port ... than you could use multiple of these setups on multiple USB ports if your PC can keep up with the data streams.

Quote:
Originally Posted by eq1 View Post
Could you do 1 from the regular +/- leads and 1 from the balancing port?
Not that I know of ... but I have not tested or asked customer service to confirm.

Quote:
Originally Posted by eq1 View Post
Anyhow, I personally probably won't buy it, but maybe someone else will find it a good option.
I doubt there are many people that need the features enough to warrant the additional cost.

Quote:
Originally Posted by eq1 View Post
Wow, maybe I jumped the gun on that one. I was just looking at the manual and the specs for power supplies, and then browsing some power supplies - and it looks like they can be really expensive. One I looked at was $400+... That's a serious downer...
The loop hole I use is the regenerative discharge option ... the PL8 can be connected to a battery for it's power to charge with and to use as a energy dump during discharge ... I like the energy efficiency of this option a great deal ... I can recycle / store about ~80% of the electrical energy of a battery discharge test/cycle ... into a 2nd battery instead of throwing it away like many other units do.

A side effect of this option is that a Battery sufficient to handle the full Watts of power transfer is not only cheaper than a AC power supply ... plus I gain the energy efficiency benefits of above ... the regenerative discharge 2nd battery can be charged for the % loss at a much slower rate thus a cheaper AC charger than would be needed for a 100% energy AC power supply.

For my personal setup ... I have two 1st Generation Hybrid Civic battery packs I bought from a junk yard ... I did testing and such back in 2007 ... to put them to a useful life and not to just collect dust ... I rewired the sticks to be 2 series 20 parallel (2s20p) ... for a 14.4V nominal battery pack of over 120 Ah ... ~1,700 Wh usable ... While the combined batteries could put out discharges at up to a peak of ~20kw and up to peaks of ~10kw charging ... I did not built it to handle that much at a sustained rate ... nor do I currently have need for a ~20kw battery source ... but it can easily handle a PL8 with no issue ... and if needed I can also use the energy in the combined civic battery for my power inverter to power any AC loads I might wish to.
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