Find the ideal location for your charge equalizer
You have a 12V auxiliary battery a long distance from the 24V battery bank (E.g. at theback 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
Where should the Charge Equalizer be mounted to minimise the effect of voltage drop on long wires?
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.
(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