AFAICR both outputs are wired in parallel internally. If you need the full 11-12A over long cable lengths and you find the wires get warm, you can use both sets of wires to your charge port. I'm only using a single set of output wires to charge at the maximum possible rate for my onboard/built-in charger on SB Cruiser; I think I present have the voltage set to 56v for my EIG NMC 14s pack. (4v / cell; I used to set it to 4.1v but the cells are over a decade old).
The manual (attached) says tthat for the B or AB versions, the other set is for remote *dimming*, as well as enable/disable. For just the A version (like I have) the other set of wires is for remote enable/disable of the unit. These can all be left disconnected if not in use. It's marked on the label of the unit at the cable end for which wire is which, for each of the different cables, or in the attached images.
Adjustment is done via the pots under the caps. Voltage is adjusted without it connected to the pack, and current is adjusted with it connected to a discharged pack (or other load that will draw that maximum current) so you can set the maximum current.
If like me you are permanently wiring the charger in, and the pack has a common charge/discharge port (instead of separate ones) you can wire it to the controller side of any shunt/wattmeter you are using (Cycle Analyst in my case) so you can use that to measure the charge current / capacity if desired.
Because the blue LED on the MW is directly connected to the output wiring, then if you have no disconnect / switch between the controller and battery, you can add a schottky diode of appropriate current / voltage rating between the positive of the MW output and the positive battery connection, so that it cannot drain the pack if left for a long time. (is only a few mA, so it would take quite a while for a big pack). I have a battery cutoff I always use when walking away from the trike, so I don't need this.
BTW, to be sure, is yours HLG-600-54A, or HLG-600
H-54A?
Mean Well HLG-600H-54A AC-DC Single output LED driver Mix mode (CV+CC); Output 54Vdc at 11.2A; IP65; cable output; CC/CV adjust with potmeter
www.meanwell-web.com
I've only ever worked with the H version, and couldn't find a manual or datasheet for a non-H version, so I don't know what the differences are.