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@SeanHacker may disagree with that one.
Definitely already have a torch though, not one that’s ever blown up on me either.
Heard, I’ve got them curing now.
Switched to black oxide for the rear, I have yet to do the same for the front though.
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Does the Makerx d100 have bluetooth, or an antispark switch?
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Antispark built in, Bluetooth available through a UART or CAN module (things like Megan, Minnie, robogotchi etc work)
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Thanks.
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Everything is all connected but it looks like im missing the wire labelled PPM? Not sure where to put it tho.
Its a VX1 pro receiver connecting to a DV4s.
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In case of one p group in a battery being to high, is it best to charge the other p groups up or the single p group down.
Thanks
Also why (what causes) one p group charge faster than the rest? My cells were balanced before I charged the battery.
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remote is uart and doesn’t use ppm
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Cool thanks 
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Cells don’t really show an imbalance in the middle voltages of the charge, only really shows at the top and the bottom. Relative there is less capacity per volt at the top and bottom so the differences become more apparent.
My opinion: Best is the least amount of work, first because im lazy but second because less work is less the battery has to do and so is less wear and tear on it. Its probably insignificant but it makes me feel better about being lazy. If one group is high, it’s faster to drain it so this is what i do. If one group is low i charge it - balancing down an entire pack to match one lower group is slow and tedious.
If the pack isn’t balancing at the top/high end of the charge for some cycles the imbalance is compounding - make sure it gets fully balanced before your next discharge and keep a close eye on it for the next few charge cycles to make sure it isn’t an indication of a bigger problem. If it is always charging significantly faster it could be a bad weld or bad group - that group has a lower capacity than the rest of them (because it’s aging or damaged or one of the cells isn’t connected). and gets full with less energy input.
If it is consistently significantly faster then you need to do something about it and start planning on repairing or replacing it soon.
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Thank you, i will discharge the one p group to match the rest. This is the packs first charge. The cells in theory have never been cycled, just coming out of a long storage. I charged it with low amps.
Could a p group charging faster then the other ever be a result of a poor bms wiring/improper guage?
Thanks again.
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If one group has higher resistance from wiring and/or connection points that could throw off balancing.
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incorrect*. The VX1 can be used in PPM or UART.
*
Unless you mean that it doesn’t use ppm while connected via uart, which would be correct.
@DaddyLong_Legs You only need the PPM cable when using the remote via PPM aka a different cable:
right now you have set up up to use UART.
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Hey i found a bad/non existent weld on one of the terminals of 5th p group. The cell disconnected is at 3.56 while the p group is at 4.171. The rest of the pack is 4.066. Im looking for advice. Understand if the pack needs to be scraped just looking for the safest option.
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Safest is to scrap it but you would probably be fine bringing the cell up to the same voltage as the others and having it welded properly. Ideally do a discharge test after the repair and check all connections with an IR thermometer to look for any high resistance spots.
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Thanks for the clarification!
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Probably doesn’t need to be scrapped yet. You probably caught this early enough if it hasn’t seen much use. That voltage disparity is huge in my opinion though - is there a way to safely discharge the battery voltage down to the low cells voltage?
What i would do: do something to insulate that cell from the group so it doesn’t accidentally connect to the rest of the p group first.
Then i would discharge that the entire pack until the weak (missing a cell) pack is within a 500mv (3.6ishv).
Then repair that missing bad weld. I would absolutely go over the entire pack and every connection to make sure it is just a one off problem - fix anything else you find and i would probably add a shit ton of silicone to lock the cells in place better. Also if it isn’t the only issue I would make a judgement call on if the pack is salvageable or a loss - you don’t want to wrap it all back up just to have it break after one season.
If everything else seems good and it is repaired well i would charge and balance it back up to full and keep a close eye for a few cycles. If it’s a smart balancer id set it to a max .010 delta. Its too fine for regular use but this is just to test a few cycles. Look hard at the repaired p group and how it behaves to make sure it isn’t showing any other weirdness.
If all is well set the balance delta back to normal i.e large (6+) p groups get .020 delta because they are more stable in their performance and a smaller delta is a bigger capacity difference but small (1-2) p groups get .035 for the inverse reason.
These settings are my opinion and based off of my accepted risk level and knowledge which are both on the crazy side of bananas 
as long as it is somewhere less than .05 it’s probably fine but i wouldn’t recommend doing less than .020 because… it’s a lot to explain so just don’t because im suddenly feeling lazy
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Probably a lot easier to bring the single cell up to voltage rather than draining the rest….
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Yes certainly easier to bring the single cell up and that’s probably what I’d do but I’m assuming Pecos is recommending the safest practice which would be to lower all cell voltages before welding. Not that I have any experience welding a cell so take it for what it’s worth.
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I would try and raise the single cell, i have no good way to acess it because the negative is welded and its in a 6s5p 21700 plastic holder. I would have to take the cell out, i can however attach to the bms leads with a 1s discharger and lower the p group, re weld, and then charge the p group
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