Find the ideal location for your CE

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Scenario:

You have a 12V auxiliary battery a long distance from the 24V battery bank (E.g. at the
back of a long 4WD or in a trailer). In this application, a CE20-13.8 would be better but
you only have a standard CE20

Question:

Where should the CE be mounted to minimise the effect of voltage drop on long wires?

Answer:

When using a CE to charge an auxiliary battery, the best results will be obtained by
placing the CE close to the 12V battery.

The input current on a CE20 (or higher) is only about 60% of the output current. So the
voltage drop on the long input wire will only be 60% of what the drop would have been
on a long output wire.

For example:

(In both cases, assuming 28V supply and 0.1W wiring resistance between the 24V
battery and the 12V battery).

Case 1: CE20 mounted close to the 24V battery- 12V battery terminal voltage (at 20A
charging current) would be 12V.

Case 2: CE20 mounted close to the 12V battery- 12V battery terminal voltage (at 20A
charging current) would be 13.4V

Updated: Oct 28, 2009 15:40