Originally posted by Sunking
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Here are the specs on the Elite BMS:
Main Screen Display: Pack Voltage, Pack Current, Battery Capacity, Alarm Message
Individual Cell Screen: Cell number, voltage and temperature
Computer Input Power: 9-20V, 120mA
Battery Voltage: 12-500V
Shunt Input: 500A = 50mV
Pack Voltage Resolution: 0.2V
Current Resolution: 0.1A
Temperature Measurement Range: -99F to +199F or -146 to +92C
Video Output: Composite Video, Color, NTSC, RS-170
Measurement accuracy: Better than 1% of Full Scale
Maximum number of cells supported: 140
Balancing Threshold: 3.55V
Balancing Current: 0.5A
Alarm Output Current: 4A surge for 100mS, 2A continuous*
Optional Data Interface: CAN
Ground Fault Detection: 2mA (5000 Ohm/Volt)
I am pretty sold on the concept of bottom balancing and monitoring for voltage drift (easy to do when it's all spelled-out for you on the LCD screen), but I doubt the bleeder boards will be doing any cell balancing with the conservative charger settings we are using.
When it comes down to it I will basically be using the BMS as my battery monitor (cell voltages, temp, overall voltage and amps in/out) and more importantly as a source for a backup LVC/HVC if my chargers/inverter do not shut down on their own. The cost for all of that is $345 (plus the LVC/HVC contactors, which I would buy anyway), and I will NOT have to buy the Victron BMV702 as my energy monitor (which costs $205), so the difference in cost between no-BMS + BMV702 and the full-system just described is only $140. If I went with no BMS I would have to figure out a way to have that secondary LVC/HVC control.
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