Battery chargers

[Brian D]

I think I am in need of a new one. How do I determine the current rating requirements for a new charger? I have shore power, and two batteries which neither one is used for cranking the O/B. I will probably have to get new batteries also, but for now, let me just deal with the battery charger.I've heard that a smart charger is the way to go. Would 30 amps be enough? These things are expensive. Oh well...

 

[captain dave]

that depends

30 amps is pretty large, 10-20 should be adequate. How fast do you need to charge and how many amps are you batteries? If they were 100 amps each, it would take a ten amp charger 20 hrs. to fully charge them from a complete discharge. You also have to consider some chargers say 30 amps, but have 3 leads, one 20 amp and two 5 amps or some variation. A 20 amp charger with 2 leads (10amps each) should be OK.

 

[Stephen]

I had the same

basic question last year (October ???) and got excellent advice. I have 2 group 24 deep cycle wet cell batteries total of 150 amp hours. At a 6% recomended recharge rate, I needed a 10 amp charger. Based on the feedback I bought the 10 amp Xantrex smart charger and it has worked like a charm...could not be happier...check the archives for more information.

 

[Nereussailor]

Xantrex True charge

I've got a Xantrex truecharge 20 that will charge three seperate battery banks and will charge every type of battery (as long as each bank is the same:AGM, Wet Cell etc.)It works great and the price is fairly reasonable for what you get.

 

[Brian D]

Stephen

Are you talking aobut the Truecharge 10Tb Battery Charger? Defender has it for $120. Makingthyme, I'll check into the Truecharge 20.Thanks guys.

 

[Malcolm Young]

Charge ratio

As has been said the size of charger depends on the size of your batteries. The general guideline is for a charger equal to or smaller than 20% of the amp-hour capacity of your smallest battery (or bank). Thus if your smallest battery is 100 amp-hours then your charger would be 20 amps or less. If you ran two 75 amp-hour batteries as a 150 amp-hour bank, then the charger would be 30 amps or less. (Canadian Power and Sail Squadron recommendations)

 

[Stu Jackson]

Read a catalog

West Marine has great Advisors, also available online, that answers your question.Also, BoatUS website.Lots of information out there.As well as here.

 

[Benny]

It depends on your usage.

It depends on how much power you consume between charges and how fast you need to replenish it. For light consumption with overnight charging capabilities a 10 AMP will be plenty. Guest makes a 10 amp (5/5) automatic two banks, three cycle charger which sells for $99. It is waterproof and vibration proof. For a daysailer or weekender it will be plenty.

 

[Brian D]

Ordered a new battery charger...

Went with the Xantrex Truecharge 20+ from Defender. I already have a 20amp charger in the boat right now, so I decided on a one-for-one change. I hope this will solve my battery woes. But I might have to get new batteries to keep everything on even par.Thanks for your collective help.