Posts: 433
Location: Cedarburg, Wisconsin | The 6 amp charger would be OK. The only rub is that if you fully drain the two batteries it would take a longer time to recharge with the 6 amp unit. Look at the amp hour ratings of the batteries, add them together and divide by 6 and that will give you some idea of the worst case time in hours you can expect to recharge the batteries. I used two batteries in parallel for many years and charged them with a simple (read cheap!) 10 amp charger hidden from the elements under an upsidedown cooler with enough space under the edges for some air movement to help cooling the charger. It got pretty rusty, but still did the job keeping the batteries charged.
The one thing you have to be aware of is that no matter what your charger is rated for, if you don't supply the AC current at the stated voltage it needs on the input side, it can't put out the DC charging current at the other end. Long smaller gage extension cords, multiple chargers on the same line, or AC voltage drops are all things you can run into at resorts on vacation trips, and all will take away the efficiency of you charger causing longer charge times.
I'd use the 6 amp unit you have this season and save the money for your upgrade to a 24V system. I'll never have another boat without an onboard charger. Too many years of lugging chargers, coolers, and rocks to hold down the coolers when it stormed taught me that just plugging in a cord and forgetting about it was definitely the way to go. If you just charge the boat in a garage, that's different. Then an onboard charger is nice but not nescessary. But when your boat is tied up to the dock for a week or more just plugging it in can't be beat. |
