you can jerry rig the DC50S to another 12v battery just to wake that battery up.
the Renogy DC50S has wakeup feature. . . so it puts out 12v power to the leisure battery terminals to wake a sleeping lifepo4.
have you got the Renogy DC50 yet?
Note the factory default is 50A charge . . . so id go intro the APP and set the current limiter to 10A with the lithium profile first - before connecting up the battery . . . you need the BT2 Renogy BT adapter plugged into the DC50.
or use cables that can deal with the larger currents. . . i normally use a 12v test light as a safety buffer to stop any inrush. see below.
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another way is using a jump lead set from the van. just a jump lead set from the vans starter battery - just to flash the terminal with a 12v test lamp or bulb.
you can use inline current limiting like a 12v test lamp, or 12v light bulb, or large 10w resistor - like a pre-charge resistor when using large inverters.
a 12v test light is best.
but only do that if you know what you doing. . .
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to do this. . .the safe way.
just use a normal jump lead from van neg to lifepo4 neg.
then use the 12v test light from van POS to lifpepo4 POS. . .
that will let a safe small current through, but allow the voltage to wake the bms....
to rase the vans voltage, just turn on large electricals like lights, heated seats, heated screen, AC etc etc . . . that will rise the vans voltage to 14.6v or so.
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