Ideas Adive for simple battery charger

rogersimms

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Ideas Advice for simple battery charger

Hi All

I have 2 batteries (24 volt) in the bow for the windless and bow thruster. They are only charged when the engine is running via the alternator. They are never charged when on shore power.

Not such a good setup as the bateries drain after a long period of time.

I want to buy a simple 24 volt battery charger connected the 240 volt mains supply so when I am on shore power or running a generator these 2 batteries are being topped up. Nothing 2 fancy but they need to look after themselves i.e permantly connected and switched on and charge the bateries as soon as 240 volts is suplied but without cooking the batteries.

Really looking for someone who has similar issue or can advise what battery charger to use or what ones to keep away from.

thanks
 
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macd

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Steer away from cheap single-stage chargers (such as car chargers supplied by Halfords etc): they'll never fully charge the batteries, to their long-term detriment.

You need a 3- or 4-stage charger. Does your boat already have a battery charger? If so, many of them have the capacity to charge more than one bank. You may find there are spare terminals on the charger for exactly your situation. If this is possible, or if you decide to buy such a charger for both banks, you'll need fairly hefty cables to reduce voltage drop from the charger to the remoter bank of batteries. This site (and many others) offer a voltage drop calculation tool: www.supercircuits.com/resources/tools/voltageDrop
 

rogersimms

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Steer away from cheap single-stage chargers (such as car chargers supplied by Halfords etc): they'll never fully charge the batteries, to their long-term detriment.

You need a 3- or 4-stage charger. Does your boat already have a battery charger? If so, many of them have the capacity to charge more than one bank. You may find there are spare terminals on the charger for exactly your situation. If this is possible, or if you decide to buy such a charger for both banks, you'll need fairly hefty cables to reduce voltage drop from the charger to the remoter bank of batteries. This site (and many others) offer a voltage drop calculation tool: www.supercircuits.com/resources/tools/voltageDrop

Thats exactly the problem I have. The installed Victron charger can only charge one bank. you can also top up the the starter batteries. there is no facilty for another bank and this was not a cheap charger invertor. The other issue is there is at least 20 feet of cable to run to the bow batteries and would need to be really hefty. Hence the reasoning for a simple marine battery charger if there is such a thing just for this purpose. I agree the halford type chargers would be no good. I will pick up the suggestion regards the sterling chargers

Thanks
 

VicS

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As said if you want to leave on all the time you need a multistage or smart charger that will not overcharge the batteries.

( Halfords do affer such chargers both under their own brand name and at least two others, although I am not aware of any 24 volt ones)

Plenty of 12 volt ones to choose from but not so many 24 volt ones it seems.

A thought or two

If your Victron charger is a suitable automatic type maybe using a VSR system would enable you to charge both batteries as well as the starter and domestic batteries

How is the charging from the alternator split between the various batteries?
Can you not use the same system?

There are several 24 volt Battery to battery chargers in Sterlings range.

These could be the answer.

They automatically cut in I think you will find when the main battery is being charged.

http://www.sterling-power.com/products-battbatt.htm

You do not mention your domestic battery bank. How does that fit into the equation? How is that charged?
 

maxi77

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There are a number of so called smart chargers for electric cycles at 24V with a relatively low output which may provide a cheap solution, the last one I bought was about £15 from Hong Kong courtesy of ebay.
 

lustyd

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Ctek chargers can also be run in series so 2 of the cheaper (£40) ones would do the trick. This is recommended in their FAQs, I'm not just guessing :)
 
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