geoff57 said:
hi
Gary my LVC boards have crossed the pond now, very nice thankyou for coming up with that. I bought 2 24way all in charge/LVC boards from you a while back for use with A123 cells, I never did populate them and have now sold the A123 cells in favor of turnigys,can those boards be used as chargers for the turnigys with slightly diffrent components, I would be looking at matching them with the same type of transformer as you got the s-350 24v linked to make the voltage needed I would make one up as a 20s board and the other as a 15s board.
Geoff
The quick answer is yes, you probably can make use of those boards, with a couple of part changes. Which version of BMS boards are these? You don't need to include the LVC portion of the circuits, but you'd still need to use one dual opto ILD2 per channel, because the LVC portion used one half, and the throttling logic used the other. If you include the throttling, you'd still need one half. You could also just leave the throttling off completely, and set the shunt point a bit lower, like I do with the balancers. As long as your cells are reasonably healthy, they will stay close enough that you shouldn't ever have a case where one cell (or block of paralleled cells...) gets over 4.2V if you have the shunts set at 4.15V. You can do this with the boards you have by changing out one resistor per channel. If you bought the BMS boards awhile ago, you probably have 75k and 180k for the divider resistors, R101 and R102. If you swap out the 75ks for 110.0k (1%...), you should hit 4.15V pretty close.
You could also use the parts with the new balancers I'm doing. There will be two versions, one with active HVC cutoff, and one without. Even for the latter, it will still turn the LED red for any channel that goes over 4.2V, it just won't cutoff the charge current. I added the cutoff function in a "daughter" card that goes on top of the balancer card. Sounds confusing, but it is pretty simple. I'll post some pics later.
I've also done a new version of the LVC board that includes 4mm bullet connections so that the main pack leads can be paralleled as well as the balancer plugs. One board can work for up to four 6s packs in parallel, or 6s4p.
I'm trying to put together combo packages for building packs that include everything required for building complete packs, except for the Turnigy packs themselves. The first one will be for 12s packs (2p, 3p or 4p...), and will include two LVC/parallel adapter boards a small board that lets you combine charge leads with the balancer plugs into a single 18-pin AMP connector that will be used for charging/balancing the 12s pack, extra-wide shrink wrap (248mm/9.75"...) and all required pigtails and/or connectors. There will be options to add a 12s balancer which fits in an extruded aluminum 3" x 4" x 1" box that includes active cutoff, and to add a Meanwell S-350-48 7.5A/48V CC/CV supply/charger. The output of the supply/charger plugs into one end of the balancer which then has a single matching 18-pin AMP connector which then plugs into its mate on the pack. Doesn't get much simpler than that, I think.
You can leave the discharge wires connected, no need to unplug anything. Just plug in the single cable/plug from the balancer and turn on the supply. The LEDs will all be orange during the CC phase and then transition to green as the shunts start to come on. If an LED turns red, it means a cell hit 4.26V and the HVC was tripped, and the charge current has been cutoff. It will reset itself after the voltage for that cell goes down below the cutoff point, plus a little. Anyway, once all the LEDs are fully green, the pack is full and all the cells should be right around 4.15V.
I'll post more about all this in the next few days. I should have pretty much everything here by tomorrow, or Saturday. I plan to offer these as complete kits, boards-only, with instructions and a Mouser BOM file and also completely assembled/tested/
-- Gary
