Boiling my batteries

[rog]

For various domestic reasons I haven't visited my boat for a couple of months so when I finally got there last weekend I did a thorough check round everywhere, obviously.

Anyway, even bothered to check my batteries and to my concern found that the 2 starting batteries needed THREE litres of distilled water although the domestic was quite OK.
Don't suppose I've checked those batteries for about a year or so (I'll know better now!)

After filling, I measured just 7 volts on the terminals with the charger off momentairily and almost 8 with the charger on immediately after - was a bit suspicious about the accuracy of the voltmeter and have since checked the thing and found it is reading incorrectly on that scale - it was probably 10 volts and slightly more with charger.

Engines started OK but anybody know what's going on - is this usual with long term shore power/charger set-up and why is it effecting the starting batteries and not the domestic?

Thanks

Roger

 

[halcyon]

Are the two batteries in parallel, and start both engines ? or what set up do you have.
What make of charger?

A flat 12 volt battery off load is 12 volt approx, on charge 13.0 volt, so 10 volt is not good.

Brian

 

[Moose]

'rog', You are on F pontoon at Chichester aren't you? Well so are we!! (F12)
If you look at my post below I went down to the boat to find my Engine Start battery flat and all the batterys needing distilled water and this was after 2 weeks of not going to the boat.
Could it be something to do with our shorepower?

Moose

I've got a boat at last!!!
WHOOPEE!!!!!!!!!!

BUT WHAT SHOULD I CALL IT?

 

[rog]

Not sure of the wiring arrangement - think I read somewhere that one battery for one engine only and both for the other but really not sure. Also don't know about the make of charger either but can find out better information when I next visit if necessary.

Just wanted to know if it's usual to have to regularly top-up.

Do the usual (Fairline) systems constantly trickle charge or do they detect fully charge status? And does the usual charger arragement parallel charge all batteries if trickle or is it selective if a detection system?

However would expect the voltage to be that low when so much of the plates aren't in fluid, surely?

 

[rog]

Moose
Almost got me - I'm actually on G38 - alongside Cassandra - remember?
I must've been reading your thread while you were posting to mine - was thinking that Halcyon's reply to yours was very impressive so was just thinking I'd better get that information he asked for for an expert reply.

 

[halcyon]

You could have one battery for each engine, and 1 bank for domestic, or 1 engine, 1engine/domestic.
Battery chargers are basically two types, one regulates each output indepedently, the other has one regulator feeding through 3 diodes to provide seperate outputs.
If you are putting quantities of water in, you have some sort of problem.
Come across this with faulty batteries, (shorting out cell links), or it could be just old batteries, a lot clearer if you know the charger type.

Brian

 

[byron]

Sounds to me like you have a shot bettery. Before you rush out and buy a new one, go into Halfords, they sell some sort of tablet, you add one to each cell and leave the batteries in situ on charge. After a few days you will see piles of crud coming out which afdter which the batteries are revived. IT WORKED FOR ME on my previous boat though I have just replaced all mine on this boat because they are the 'sealed for life type'

<font color=red> ô¿ô</font color=red>
<A target="_blank" HREF=http://www.freeware.mcmail.com/435.htm>http://www.freeware.mcmail.com/435.htm</A>[/b]

 

[NorthernWave]

My gf is down at Chich at the moment and she tells me that shore power is down, she sitting with old genny pumping away.???



Relaxation starts at the pontoon gate