Electrical; Power Cables; Parallel Configuration - MG HE Series Manual

7.4 Electrical

This chapter describes the installation and connections of the electrical wiring.

Power cables

Cable lengths need to be taken into account when designing a battery system. Batteries can be
placed in parallel, for example in 24 VDC systems, or in series up to 144 VDC.
NOTICE:

Use the correct cable type for the applicable system voltage.

Use the correct fuses for the applicable cable cross-section and voltage.

We recommend to size the cables to limit voltage drop to 1% or less.
NOTICE:
Cable lug and battery must be cleaned before connection to ensure a low
resistance connections. Check these power connections for excessive
temperatures during a load test.

Parallel configuration

The battery module can set in parallel to create a larger system capacity. The MG Master BMS can
handle up to 96 HE battery modules. Meaning that a 24 VDC system can have 96 HE battery modules
in parallel. For a 48 VDC system is would be 48 HE battery modules.
CAUTION:
Make sure the voltage of each battery module is equal when connecting them in
parallel. Excessive high uncontrolled currents can flow between battery modules
when the voltage is not equal. This can damage the batteries and might lead to
other damage or injury.
NOTICE:
The power cables of each battery module need to have matching lengths as good
as possible when connecting battery modules in parallel.
Battery modules can be connected separately in parallel to a Master LV. It has four power
connection positions where four batteries could be connected. Refer to the Master LV manual for
more information.
Figure 16 shows the most basic parallel connection that is possible. The power connection of each
battery is directly connected to a Master LV.
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Version 2.3 – 21-9-2022