Hello Brain Pool- I have a 1987 Gulfstar M/Y with some sort of monster battery chargers (2), or at least large cabinets. I have 8D batteries and each charger is connected to 2 batteries. One bank was found to be overly hot to touch, and radiating heat to the other 2. The overheated pair now test bad or 75% of charge on a load tester. I would like to replace these monsters with the latest technology but don't know where to start. Would someone please bring me up to speed. Thanks
How old is your batteries? For old lead acids 4-5 year is max, unless they are Rolls. AGM can last a bit longer. Get a new smart charger, like a Noco or a Victron, usually 10% of the battery capacity should do. (300 amp/hrs battery for a 30 amp charger) That was the golden rule a few years ago but cut it in half unless you are a liveaboard and need full power all the time running fridge, freezer, etc..
Thanks Norseman -Bats about 4-5 yrs old. How do the new charger or chargers install? All of the wires from the old boxes run to the 3 battery switches and breakers. Is the isolation built into the charger to protect alternators on the engines, is this a diy install? I'm really lost in this arena.
Not sure what you mean by protecting the alternators? Even if you start the engines with the battery charger on it shouldn’t hurt anything. (At least it never did in my life on numerous boats, but if you are starting the engines to go boating shore power should already be disconnected) A battery charger installation can be diy, but if you are not sure, hire a marine electrician, cheap insurance. Your charger may also be an inverter, converting 12 volt DC to 115 volt AC, best to make sure what you have before buying a replacement. Post a picture, it should be easy to tell from make and model number,
Sounds you would be best to hire a pro. Down here batteries tend to have a shorter life. Mine replaced every 3 years and next time, plan to explore 2 smaller ones for each 8-D as neighbor had done.
Your chargers may be failing, but... they also might be fine. I'd suggest you replace the bad batteries first. There are footprint (and weight) options, so now would also be the time to decide whether you want to stay with 8Ds or not. (I assume you've got flooded batteries, so you might or might not consider AGMs, depending on how easy it is for you to service flooded batteries. That's another discussion, but see next...) And then see if you can identify chargers, find the manual, etc.... and assess chargers again, after that. Newer chargers can bring advantages to the table (for example, better voltage flexibility for AGMs or other types) but where you want go end up and how to get there can take a bit of study. Ref "Each charger is connected to 2 batteries." That could imply two separate 12VDC battery banks for each charger, or it could instead mean one bank of 24VDC on each. Or even one of each of those configurations. I'd assume the former given your engine(s) probably isn't (aren't) huge... but stuff like that becomes important when you try to figure out the existing architecture, the way forward, etc. ProMariner's ProNautic line of chargers (same as Sterling models) have been decent for us. And Victron products have a decent reputation (our new invert/charger is Victron, seems fine so far). -Chris
