1.Mount the BMS preferably on a vertical surface, for optimal cooling.
2.Determine the rating of fuse AB (see figure and table 1). The fuse on input AB doubles as a shunt. The BMS will limit the input current according to the rating of this fuse. Choosing the right fuse will prevent overheating of the alternator and/or DC cabling.
3.Determine the rating of fuse LB. This fuse should be rated in accordance with the expected load current and the cross section of the cabling to th load.
4.Disconnect the cabling from the plus pole of the starter battery.
5.Pull off the REMOTE on/off connector to prevent unwanted switching of the BMS.
6.Install and connect all electrical cabling and fuses AB, LB, but leave the plus poles of the Li-ion batteries and starter battery disconnected.
7.Daisy-chain the battery control cables between the Li-ion batteries and connect to the BMS.
8.Connect the plus cabling to the Li-ion batteries and the starter battery.
9.Reinsert the REMOTE on/off connector on the BMS. The BMS is now ready for use.
a) A battery charger can be connected to input AB instead of the alternator.
b) The Li-ion batteries can be charged as well as discharged through input/output LB.
c) When a load with a large electrolytic capacitor bank (such as an inverter or inverter/charger rated at 1200VA or more) is connected to LB, the BMS will limit its average output current during start-up to approximately 80A. Therefore the capacity to simultaneously start-up other DC loads is limited to 80A. Once the capacitor bank is fully charged, the current limit increases to 400A.
BMS 12/200 specification
Maximum continuous discharge current, LB
200A @ 40°C
Approximate cut-off voltage
DC connection AB, LB and battery minus
DC connection battery plus
Battery being charged through Power Port LB
Power port LB active
Dimensions (hxwxd in mm)
65 x 120 x 260