16s 100ah bank
- Thread starter Kouros
- Start date
What would be the amperage on the bms 80,100,150,200, or 250? for this bank 48v 16s 100ah cells.
Ampster
Renewable Energy Hobbyist
Only you can answer that, based on your loads.
Let’s say i am operating a wood shop so the load will very from 4a to 100a for the 5horse power compressor kicks on
Ampster
Renewable Energy Hobbyist
100 Amps for how long and what voltage? 48, 120, or 240 volts.
Last edited:
Start up on compressor is 80a runs at 40a so just for start up. The bank x3 is 48v each (16s-)(3.2v 100ah each)
Ampster
Renewable Energy Hobbyist
The Overkill BMS has a setting for the length of the surge. If long enough for your surge then 150% of 40 Amps would only be 60 Amps. A 100 Amp BMS would work. I am assuming 48 volts but have not heard of 48 volt compressor. Check your device.
The compressor is not 48v. I am connected to a growatt 48v split phase charge/controller 120/240. The compressor is a 110v unit
Ampster
Renewable Energy Hobbyist
That changes the equation. Can you do the math or do you need help with that?
What math equation are you referring to?
Ampster
Renewable Energy Hobbyist
The math to convert the 40 Amps at 120 volts to the Amps that your 48 volt pack will see. Figure 10% loss through inverter.
Snowboater
Off grid - in the sun on The High Road to Taos
- Joined
- Jan 12, 2021
- Messages
- 11
Since the Overkill BMS is rated at 100A @ 48V and you have three banks = 3 BMSs = 300A @ 48VDC. The math is 48V -> 120V. A=W/V. Since you're dealing with 300 x 48 = 14,400 Watts. Then... 14,400 / 120 = 120A. Less 10% that the inverter gets as payment for doing it's job - you get roughly 108 Amps @ 120V - be safe and say 100A. Now things get squishy... The BMS will overperform for a short while (not spec'd on this particular BMS - maybe 5-20 secs) long enough to start an electric motor, but the leads on the BMS are just a couple 8ga wires. You will have 6 of them with 3 BMSs, but my guess is they will warm up even at an amperage lower than your 100.
