to expand on boost mode with the wfco. On the 55A unit at least, the algorithm is basically.
1) the WFCO turns on, applies a charging current (or voltage,don't recall which) and THEN looks at the voltage at the WFCO OUTPUT terminals. If it is below a threshold (13.2??) it stays in bulk mode, otherwise drops down. Therein lies part of the problem. If you have a small battery bank, or a long run to the batteries, or small cable, or any combo, the voltage at the WFCO OUTPUT voltage will be high enough for it to think the battery is charged enough to drop out of bulk mode charging.
The PD and other units look at the converter output BEFORE appling an output voltage and look at the battery voltage. If it's below a threshold (13.2V) or so they go into bulk mode. so run length, battery resistance, cable size etc. don't keep them from going into bulk mode, but they do have an effect on charging current etc.
So MEX: if you can put the WFCO close to the batteries, with fat wire, it should work fine.
all that said, the wfco is a nice charger if your situation lets it go into bulk mode. it is much closer to a constant current source than many others in bulk mode, and is quite and reasonably robust.
