Capnbob

Thanks for the comments. Some responses: "An ammeter is also essential when you’re out and about in order to simply determine end of charge." Do you mean seeing when I've used up everything I put in at the last charge? That makes sense, and explains why Ah counting is so valuable "If you are able ... to determine the state of charge with a voltmeter while the batteries are under load..." Good point. I've seen the necessary voodoo described somewhere on here, so presumably it's learnable. Tempted by the Smartguage, but wonder if I can justify £120. "we need to know your daily usage, how much time you’ll spend on shore power, and the size of your battery bank" Point taken, but I have no idea myself yet. At the moment we're living on board, and mostly stationary (but with shorepower), but eventually I anticipate a more leisure usage pattern. No heavy use items, and I'm hoping to reduce where I can, such as changing all the halogen lights for leds. "when you say exposed inverter tails do you mean wiring where an inverter used to be? " Ah, no, sorry. There is a working 1500w inverter, but never switched it on yet. And yes, I should have said multimeter (voltmeter), not ammeter. The tails are exposed (which I must fix) but which does at least offer a convenient route to the battery terminals for checking voltage. Otherwise, where should I check the voltage? " And if the combi has gone, what is the shore line connected to? " Consumer unit with 2 circuit breakers. Simple swapover of shoreline socket to inverter output when on the canal. "I have all five and the batteries are NiFe." Realy useful summary, thanks, with pointers for much research. "Many battery monitors can only monitor up to 200A" Yes; keen to make it all forwards compatible, and just the sort of thing I was concerned about when I mentioned authoritative - but old - threads. This is all letting in some light through the fog, and I'm very grateful. If it's easy I'd love to hear what actual devices people use/would get if upgrading - it would really help me scope my own project.

I hoped this would be so easy. Oh dear... Acquired a 13 year old boat in October, took 10 days to sail it back home, and moored up at marina with 240v shoreline. All 12v services (from 3 batteries) seemed fine. I assumed there'd be a 240v battery charger, but went looking when the lights started going dim after 24 hours and discovered not only is there NOTHING to recharge the batteries (apart from the second alternator), there's no battery management, not even a simple meter (apart from when I stick my ammeter into the exposed inverter tails). This obviously needs rectifying, and I'm wondering what might be a sensible "standard" setup for a boat that's used about equally between liveaboard, holiday cruising and moored empty. No, I know there is no standard setup, but I'd be grateful for ideas for a shopping list - starting from the nothing I've got - for a system to get this right before I ditch these batteries and buy new ones (which I think will happen quite soon; don't think these will charge above 12.5v). BTW I *have* waded through the forums for answers, and forgive me if I've missed an obvious summary somewhere, but a) answers on individual system elements tend to be spread between several separate topics; and many apparently authoritative recommendations are now years old so potentially out of date. Thanks for your thoughts...