Batteries won't float...

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tyce

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On the charger that is:)

Electrics aren't my strongest point so Im looking for some advice.

My 2x110ahr leisure batteries whilst sat on the mains charger are only reaching 13.3v, not a massive problem except I have installed a battery to battery charger for the thruster that needs 13.6v to kick in.

The manual for the charger (Dolphin All in One 12v 20A) states float voltage as 13.8V. The engine battery which comes off a different feed from the same charger is reaching 13.8V but not the house batteries.

So im not sure if its the charger or the battery's, I guess the way to confirm it is swap leisure and start battery around but does anyone on here know if its likely to be the charger or battery that is at fault?
 
Your battery charger has a total output of 25 Amps over three outlets . Suspect you are trying to get a quart out of a pint pot. Not only are your batteries not floating I suspect they never even reach the point of equalisation. Possibly need to get a different charger.
You have got it using the correct charging program for your batteries?

Charger Spec

https://www.google.com/url?sa=t&sou...Vaw0AJJnNsnV-LFLsKt99CJSc&cshid=1603927591850
 
Thanks all, mine is the older charger than that version Bilge diver but probably similar.

Thing with it is its not even trying to go into boost mode which I know because the fan does not kick in which it should when in boost.


Will try what's been suggested and disconnect the batteries and just run it on one at a time and will report back.

Thanks all.
 
Your charger should be plenty powerful enough. I suspect you have a dodgy battery.
 
tyce said:
Thanks all, mine is the older charger than that version Bilge diver but probably similar.

Thing with it is its not even trying to go into boost mode which I know because the fan does not kick in which it should when in boost.

Will try what's been suggested and disconnect the batteries and just run it on one at a time and will report back.

Thanks all.
Click to expand...

Is there any reason why you cannot power the B2B charger for the thruster battery from the engine start battery.
It wont run the battery down because it will cut out at the cut out voltage but will cut in at the float voltage you are seeing at the starter battery and whenever the engine is running
 
Bilgediver said:
Your battery charger has a total output of 25 Amps over three outlets . Suspect you are trying to get a quart out of a pint pot. Not only are your batteries not floating I suspect they never even reach the point of equalisation. Possibly need to get a different charger.
You have got it using the correct charging program for your batteries?

Charger Spec

https://www.google.com/url?sa=t&sou...Vaw0AJJnNsnV-LFLsKt99CJSc&cshid=1603927591850
Click to expand...

25a for the OPs batteries is correct. Even a 10a charger should get the batteries charged, just take longer.
 
VicS said:
Is there any reason why you cannot power the B2B charger for the thruster battery from the engine start battery.
It wont run the battery down because it will cut out at the cut out voltage but will cut in at the float voltage you are seeing at the starter battery and whenever the engine is running
Click to expand...

That's just a bodge. His domestic batteries should reach the correct voltage, so that needs to be rectified.
 
tyce said:
Thanks all, mine is the older charger than that version Bilge diver but probably similar.

Thing with it is its not even trying to go into boost mode which I know because the fan does not kick in which it should when in boost.


Will try what's been suggested and disconnect the batteries and just run it on one at a time and will report back.

Thanks all.
Click to expand...

If the batteries are charged it won't go into boost mode. You do need to check the batteries though, i also suspect a faulty domestic battery.
 
VicS said:
Is there any reason why you cannot power the B2B charger for the thruster battery from the engine start battery.
It wont run the battery down because it will cut out at the cut out voltage but will cut in at the float voltage you are seeing at the starter battery and whenever the engine is running
Click to expand...
PaulRainbow said:
That's just a bodge. His domestic batteries should reach the correct voltage, so that needs to be rectified.
Click to expand...

Why would tis be a bodge.?

Explain the technical reasons why the B2B charger should not be connected to the engine start battery.
 
Paul one point no one seems to have picked up on is that these chargers claim to be able to deal with all types of battery. Is this dealt with automatically or is it a user setting for each and is it possible this charger is set incorrectly?
 
Bilgediver said:
Paul one point no one seems to have picked up on is that these chargers claim to be able to deal with all types of battery. Is this dealt with automatically or is it a user setting for each and is it possible this charger is set incorrectly?
Click to expand...

Any changes in battery type need to be done manually as a rule. I suspect it's set correctly, but wouldn't hurt to check.
 
VicS said:
Why would tis be a bodge.?

Explain the technical reasons why the B2B charger should not be connected to the engine start battery.
Click to expand...

The B2B charger can be connected to either bank. But moving it from the domestic bank to the engine battery is, in this case, a bodge because it is not addressing the underlying issues with the domestic bank.
 
Although it has 3 outputs the charger seems to have only one selectable charging regime. Perhaps the charger recognises the fact that the engine battery has reached full charge so switches the whole charger to float mode. The 13.3 V on the house batteries would support that.
 
alahol2 said:
Although it has 3 outputs the charger seems to have only one selectable charging regime. Perhaps the charger recognises the fact that the engine battery has reached full charge so switches the whole charger to float mode. The 13.3 V on the house batteries would support that.
Click to expand...

No, it wouldn't. The float voltage is 13.8 so the house batteries should be at 13.8v when on float. Like others, I suspect a faulty battery.
 
pvb said:
No, it wouldn't. The float voltage is 13.8 so the house batteries should be at 13.8v when on float. Like others, I suspect a faulty battery.
Click to expand...

If the charger switched to 13.8V as soon as the engine battery was fully charged then, if the house bank was well depleted, I could easily imagine that the house bank would take a very long time to get to 13.8V.
 
PaulRainbow said:
The B2B charger can be connected to either bank.
Click to expand...

I asked , "Is there any reason why you cannot power the B2B charger for the thruster battery from the engine start battery. "

The answer to that question then is simply, "No"
 
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