maybe the wrong category for this but
how bad is the voltage drop under load on the p42a? my 12s pack goes from like 48-49v down the 41v when under load. what is the correct voltage cut off start and end on vesc tool?
12s is fine. But whats the P number is what matters in this case, also how many amps are you pulling at that moment?
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12s2p for battery config. running my esc at 30 amps per channel
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I think thats pretty normal. At 50A total I am losing about 1.4V in 12s7p with the same cells.
If you are pulling 60A thats 30A per cell that is a lot to ask from a single cell.
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i thought 30 amps was pretty standard for these p42a cells
30A is the realistic limit for continuous discharge.
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As the chart shows. At 4.0V if you ask 30A from the cell you are losing about 0.7V due to sag. Times 12 thats 8.4 Volts.
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The cells can handle current that high (with reduced cycle life) but you’ll get a lot of sag. That’s a verrrrry high power level for a single cell.
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I’ll dial it down to 25amps per cell. What is a safe cutoff voltage?
I go 39 and 35. Its slightly aggressive but safe.
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Safe? No such thing, there’s always some risk. 
But anything over 2.5V/cell is above the low voltage limit, I’d stay over 36V soft limit and 33.6V hard limit though to help extend cell life a little bit.
The higher you go the less range you get but the longer your cells will last…anyways a tradeoff!
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