Battery Charging on a wooden boat

Rosie1963

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ramblinginrosie.blogspot.co.uk
I have a Rutland, but now that I am in the paintshed, and it is not rotating, my batteries have gone flat in a day. I think the Rutland was providing most of my battery charging. So in a way it is good I have discovered this in the paintshed!

I think I need to get a battery charger from the mains, not a permanently fitted one as I dont like the idea of fizzing away in a Marina! I need one I can connect to each battery and charge over the winter when out or at home when I take the batteries out. I was looking at Ctex ones or Sterling.... I am not great at electricity so was wondering what others do? I have two old 120am hours lead acids.
 
I have two 120AH batteries too. They are the cheapest of the deep-cycle lead acid sort, now a couple of years old. I have a single solar panel and that seems to keep them charged both summer and winter, though I can see that wouldn't work if you were in a shed! I also have a ctex charger, just their cheapest one, and I have used that to do a full recon charge of each battery while the boat was out of the water, but I haven't had to use it to keep the batteries topped up.

I think that, unless you are still running something heavy duty off them, batteries that go flat in a single day are, sadly, knackered.
 
I have to agree that your batteries may well be past their best unless you are running a heater or fridge off them 24/7. I had a small (10w) solar panel on SR to keep one battery topped up when left. That way I could always be sure of starting the engine to top them both up. They are cheap enough at 10-20 quid and need no regulator as they are low current trickle charging. If your batteries are not old (over 3 years) check the regulator on your windmill, overcharging can severely reduce battery life.
 
There are several good sites on the subject, explaining charge and battery life cycles.

One is
http://www.emarineinc.com/pages/Batteries-Maintenance-101.html

At the end of the day a modern "Smart" charger (also known as Intelligent) is way to go for a mains powered solution. Will switch to maintenance mode when charging is finished and so can be connected for extended periods.

For storage a fully charged battery, disconnected form all consuming devices, will keep well in cool(ish) places (eg. on the boat)
 
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I have two 120AH batteries too. They are the cheapest of the deep-cycle lead acid sort, now a couple of years old. I have a single solar panel and that seems to keep them charged both summer and winter, though I can see that wouldn't work if you were in a shed! I also have a ctex charger, just their cheapest one, and I have used that to do a full recon charge of each battery while the boat was out of the water, but I haven't had to use it to keep the batteries topped up.

I think that, unless you are still running something heavy duty off them, batteries that go flat in a single day are, sadly, knackered.


Appreciate that they might be kackered. Will go for CTEK and see what happens over weekend. If not, next week I will get new Batts - ouch.
 
Get the batteries tested first before splashing out on a charger - unless you anticipate using a charger a lot in the future. If you want charging on board then a proper marine charger is the way to go. no reason why it should not work on a wooden boat. If you just want something to keep the batteries topped up in the winter or at home then a smaller output charger may be more suitable.
 
I too went with C-tec charger. I plug it in for about one day a month in the winter.

I leave the boat pluged in, in the winter and I use a Dimplex frost heater and de-humidfier. I have not seen anything to cause concern or make me think about changing this.

The anode does get a little eaten - enough to know its working but not so much as to worry about.
 
I too went with C-tec charger. I plug it in for about one day a month in the winter.

I leave the boat pluged in, in the winter and I use a Dimplex frost heater and de-humidfier. I have not seen anything to cause concern or make me think about changing this.

The anode does get a little eaten - enough to know its working but not so much as to worry about.

If you leave the boat plugged into shorepower and the shorepower earth is bonded to the DC negative and the anodes you run the risk excessive rate of loss of the anodes unless you have a galvanic isolator fitted.

If the boat is not left plugged in for prolonged periods there is no problem.

If the is no connection between the shorepower earth and the anodes there is no problem.

If the above does not apply but you still don't suffer from rapid loss of zinc you are lucky, but keep an check on the situation.

Also be aware that loss of zinc does not necessarily mean the anodes are working. It could be due to some other cause.
OTOH very low or zero loss of zinc would indicate that the anode is not working.
 
If you leave the boat plugged into shorepower and the shorepower earth is bonded to the DC negative and the anodes you run the risk excessive rate of loss of the anodes unless you have a galvanic isolator fitted.

If the boat is not left plugged in for prolonged periods there is no problem.

If the is no connection between the shorepower earth and the anodes there is no problem.

If the above does not apply but you still don't suffer from rapid loss of zinc you are lucky, but keep an check on the situation.

Also be aware that loss of zinc does not necessarily mean the anodes are working. It could be due to some other cause.
OTOH very low or zero loss of zinc would indicate that the anode is not working.

The shore power is provided by the cable presented into an outdoor 13 amp socket from b&q. It's identical to the wiring you would have for an extension lead except the socket is screwed to a bulkhead. It is not earthed on the boat. I put the socket on for convenience and because it has an rcd inbuilt.

The 12 system is earthed to the anode.

I guess the only connection between boat and mains is when the charger is in use.
 
The shore power is provided by the cable presented into an outdoor 13 amp socket from b&q. It's identical to the wiring you would have for an extension lead except the socket is screwed to a bulkhead. It is not earthed on the boat. I put the socket on for convenience and because it has an rcd inbuilt.

The 12 system is earthed to the anode.

I guess the only connection between boat and mains is when the charger is in use.

Thats OK then. It should not cause any corrosion problems.

It is also right that you have an RCD on the incoming supply.

The campsite power units:

http://www.kampa.co.uk/mains-equipment/pitch-power-mono and http://www.kampa.co.uk/mains-equipment/pitch-power-trio

are convenient ways of providing a semipermanent shorepower installation. They have an mcb in addition to the RCD



You do mean it is
 
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