Installation Guide

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Fig. 9.3 shows two strings in parallel; each string consists of two 6V batteries in series. For
example, say each battery has 225 Ah. Each string would have a voltage of 12V with a capacity
of 225 Ah. When these strings are paralleled, the total capacity of the battery bank will be 12V
at 450Ah. Notice that the cables connecting the batteries in series and parallel are of heavier
gauge than the ones coming from the controller. These cables have to be of heavier gauge
because when power is drawn from an inverter, it involves large amounts of current. This
interconnection cable is often sized according to the power of the inverter.
Also, the negative cable from the controller to the battery should be placed at the opposite end
of the battery bank.
Figure 9.3 shows this connection.
9.3 Series – Parallel connection of batteries (12V)
Figure 9.3 Four 6V batteries connected in series – parallel