Since I know that there are a few very knowlegable electrical types on this list, what charger would you reccomend for my friend who has a battery bank of 4-Grp 31's totalling 500 amps. Also 1-grp 27 for starting. Battery charging is a problem over the winter when the boat is on the hard. He can only leave the charger on for one 24 hour period per month. Yard rules. So we need (I think) a three stage, bulk charge, equalizer (or conditioning) cycle and a float. During the sailing season he is on a mooring and the charger is not used. I would appreciate reccomended brands and models.
Frank Langer
1984 Ericson 30+, Nanaimo, BC
I''m not an electrical expert, but has he considered a solar panel to trickle charge the batteries to maintain them over the winter?
Frank.
Frank.
ted_reshetiloff
Contributing Partner
Xantrex True charge 50 amp or the 20 amp. Cant imagine sitting on the hard he would lose more than either of these chargers could replace in a 24hr pd once a month. Lets say the bilge pump runs one hour a day to draw 7 amp hours. Probably never get close to that but lets just say it does. Thats 217 amp hours in a month. Assuming perfection in the charger which is not the case but keeps our example easy a 20 amp charger would be done in 10.85 hours. Not exactly the way it would work but IMHO close enough to tell you that a 20 or 50 amp multi stage charger like the True Charge would do just fine. I run the 20 amp version with a 200amp hour bank.
Tom Metzger
Sustaining Partner
If it was me...
If it was me (in fact, it is me, but they are in the basement), I would go to Sears or an auto parts store, buy a 10 or 12 amp simple charger. I would go to the boat every two or three months and sit around for about two hours charging and then I would go home and have a cocktail.
I definitely would not spend a lot of money on a charger that was intended to quickly recharge depleted batteries if I was only going to top off batteries in the winter. If the batteries are in a cold area they would probably be OK for the winter with no charging if they start with a good charge. Cold slows the discharge rate.
Where I sail, Lk Champlain near the Canadian border, lots of people leave their batteries on board with no charging over the winter.
I am sure that lots of advice will come in with more expensive options.
BTW, don't forget all of the normal warnings: don't mix battery types, make sure that there is enough water, etc. Different sizes are not a problem.
YMMV.
If it was me (in fact, it is me, but they are in the basement), I would go to Sears or an auto parts store, buy a 10 or 12 amp simple charger. I would go to the boat every two or three months and sit around for about two hours charging and then I would go home and have a cocktail.
I definitely would not spend a lot of money on a charger that was intended to quickly recharge depleted batteries if I was only going to top off batteries in the winter. If the batteries are in a cold area they would probably be OK for the winter with no charging if they start with a good charge. Cold slows the discharge rate.
Where I sail, Lk Champlain near the Canadian border, lots of people leave their batteries on board with no charging over the winter.
I am sure that lots of advice will come in with more expensive options.
BTW, don't forget all of the normal warnings: don't mix battery types, make sure that there is enough water, etc. Different sizes are not a problem.
YMMV.
Howard Keiper
Moderator
As usual, Tom has the right idea.
I, myself, use a simple 20A ferroresonant type charger (the inexpensive, but very capable, extremely reliable "low end" variety of charger). Fully charged batteries can be expected to self discharge over time...weeks or months maybe, but nothing an hour or two on the charger won't handle. A solar array is a much more elegant (expensive) solution, for sure, but not as much fun, as Tom alludes.
howard keiper
Sea Quest
Berkeley,
I, myself, use a simple 20A ferroresonant type charger (the inexpensive, but very capable, extremely reliable "low end" variety of charger). Fully charged batteries can be expected to self discharge over time...weeks or months maybe, but nothing an hour or two on the charger won't handle. A solar array is a much more elegant (expensive) solution, for sure, but not as much fun, as Tom alludes.
howard keiper
Sea Quest
Berkeley,