battery charger making noise

[eagle160]

Good afternoon,

In my sailboat there's a Sterling Marine battery charger installed (12v , 25 amp ) which is around 2.5-3 yrs old (I suspect, just bought the boat). We haven't used the boat for about 3 months and now started using it (lying in the med) but yesterday when we plugged in the shore power cable and switched the charger on it started making a humming noise which wasn't there before .

I can't be sure whether it's still charging as I don't want to keep it on for too long to confirm (my volt meter indicates approx 13.2v on the output which is below 14.4 but it could be in a different charge cycle I guess. I have 3 batteries which are ageing but filled up, and seem to keep their charge still reasonably well.

Would you suspect a faulty charger ? If so how can I confirm it before purchasing a new one ? anything else you recommend me to look at? If I need a new one any italian brands anyone can recommend (not sure Sterling will be sold here in Cagliari, Sardinia)

Thanks for the help

 

[DaveS]

A quick initial test would be to put your voltmeter on the house battery bank with the charger switched off, note the reading, then switch the charger on and see whether the voltage changes: a rising voltage implies the charger is doing something, a static or falling voltage implies it's faulty.

 

[Mrnotming]

Agree,and also consider if there is a shorted cell on any battery.
So your charger is trying too hard, trying to make 14.v volts appear from a now 10V battery. Beware of Hydrogen accumulations if this proves to be the case.(lighter than air so hopefully with a bit of decent permanent battery area ventilation hydrogen will dissipate before the mixture with O2 becomes explosive.
If the cells have screw top fillers or a strip that can be prised off, you can (goggles) peer down the holes whilst under charge and see if one cell is bubbling more than the rest.This could be the faulty cell.A high discharge meter as used by auto electricians is useful, even to borrow.This will cause faulty cells to gas also.
Best of luck, do not persist, change the battery/s

 

[Mrnotming]

Charger Hum

Just noticed the lying for 3 months bit!
If nothing was left on loadwise, good batteries should be still be mostly in charged state.
If something wired in like a navtex has deep discharged the batteries, then your charger might well make a hum as it tries to recover from a fully discharged state?
So if you can get them to hold the charge in a few days, as the OP said, disconnect charger, and let the batteries rest for an hour or two.Measure voltage and if not 12.7, at least one of them is goosed!.Many on forum will recommend replacing batteries simultaneously,and there is merit in this.you'll have to decide this yourself.

 

[Tony Cross]

Mine (not Sterling) has a cooling fan that comes on when it's under load and getting warm, that makes a humming noise. Perhaps that's what you're hearing?

 

[Grumpybear]

Mine (not Sterling) has a cooling fan that comes on when it's under load and getting warm, that makes a humming noise. Perhaps that's what you're hearing?

The fan on mine (a Newport) started making a noise. It was the bearings on the cooling fan which is identical to the ones fitted in PCs. I bought and fitted a replacenent from Maplins.

 

[sealegsjim]

Mine (not Sterling) has a cooling fan that comes on when it's under load and getting warm, that makes a humming noise. Perhaps that's what you're hearing?

So does mine

 

[sailorman]

Good afternoon,

In my sailboat there's a Sterling Marine battery charger installed (12v , 25 amp ) which is around 2.5-3 yrs old (I suspect, just bought the boat). We haven't used the boat for about 3 months and now started using it (lying in the med) but yesterday when we plugged in the shore power cable and switched the charger on it started making a humming noise which wasn't there before .

I can't be sure whether it's still charging as I don't want to keep it on for too long to confirm (my volt meter indicates approx 13.2v on the output which is below 14.4 but it could be in a different charge cycle I guess. I have 3 batteries which are ageing but filled up, and seem to keep their charge still reasonably well.

Would you suspect a faulty charger ? If so how can I confirm it before purchasing a new one ? anything else you recommend me to look at? If I need a new one any italian brands anyone can recommend (not sure Sterling will be sold here in Cagliari, Sardinia)

Thanks for the help

There is a transformer within it that is possibly making a humming noise as does my 240 > 110v transformer

 

[VicS]

There is a transformer within it that is possibly making a humming noise as does my 240 > 110v transformer

Modern stuff does not have the heavy old mains transformers that hum. Instead a load of electronic jiggery pokery and a relatively small and light transformer that operates at a higher frequency.

 

[aitchem]

Mine (not Sterling) has a cooling fan that comes on when it's under load and getting warm, that makes a humming noise. Perhaps that's what you're hearing?

My Sterling does this also, when switched on the fan goes full blast for a while, then subsides slowly to a light humming.

 

[eagle160]

Hi all. Thanks for the helpful responses. I've bitten the bullet and ordered 3 new batteries, delivery this afternoon. Hopefully that sorts it, voltage increases with charger on so it seems charger isn't broken.

There's a fan on the bottom but not spinning - there might be one inside I guess haven't opened it.