REC ACTIVE BMS 4S
13
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Contactor Connection:
Charging/discharging contactors are driven by charge/discharge relays in the BMS. If there is high input capacity (>
2,000 uF) at the charging sources/discharging loads, pre-charge should be used to avoid high current spikes when
the contactor is turned on. High current spikes degrade the contactor, cells and input capacitors in the electronic
device. Fig. 8 shows contactor connection with or without the pre-charge circuit.
Figure 8:
Contactor connection schematics.
Parallel Cells Connection:
Capacity can be increased by connecting multiple cells in parallel and then connect these sub-packs in series. Fig. 9
shows 3P4S connection with 3 cells in parallel and 4 pack like this in series.
Figure 9:
3P4S battery pack connection.
