El_Steak wrote:Have you tested it to charge your 24s Lipo pack with your 4 x S-350-24 meanwells in series? (I have the same setup)
Richard was suggesting that with such a setup 2 current limiters might be required.
No, not with four MW in series, but I think it should work. What Richard was worried about is whether pulling down on just one MW sense line was going to be enough to pull the charge voltage below the pack voltage, which cuts off the current flow, when the pack is empty. This still needs to be tested, but my gut says it should be fine, based on what I've seen so far. On a dual SP-320-24 setup, I've seen the voltage drop from 50.1V down to 42.0V, when I ground the HVC line.
I don't like working with 100V, so my 24s setups are split into two 12s3p packs. Right now, during testing, I'm just using a two MW configuration, and a dual CellLog 12-channel balancer unit, and charging/balancing each pack separately. Here's some pics:
The pot in the middle controls the charge current, in the initial CC phase. The pot on the right controls the end-of-charge low current shutdown set point, which is adjustable for 0-2A. The first pot, on the left, adjusts the amount of "pulldown" voltage. The LED is red initially, orange if the current limit function is active, or if the HVC line is tripping, and green in the shutdown/float mode.
As I said above, this little board completely replaces the standalone Charge Controller, both the previous v4.0x variants, and the newer relay-based versions. The HVC signal can be from either a CellLog-generated HVC "alarm" output, the HVC portion of the previous LVC/HVC boards or from either a v2.x or v4.x BMS board.
Next up, I'll be testing this with a new 12-channel CellLog CMS/Balancer unit, and then after that, with a three MW "stack" to be used with my 18s2p packs.