What charger

[Martin Hurst]

Got a 3.3ah battery for the sonar (hate the words Fish Finder!!). Can i use my 12v car battery charger (8 amps) or is that going to blow the house up. Advice appreciated as these electrics arent my strong point!!

 

Also note differing advice re an inline fuse. Purchased my finder from a reputable dealer who advised that despite all the manufacturers advice to fit one , it was irrelevant as long as the battery was removed from the unit when charging!!

[Starvinmarvin]

Martin,

 

I'm not an electrician, but when I bought my 3.3ah battery I bought the charger with it from Maplin, the charger is designed for that specific ampage of battery. When checking out the chargers I found that you needed a different charger for the 7.2ah, there has to be a reason for it, surely it can't be that they want you to spend £20 everytime you get a different battery, or can it. Personally I'd get the right charger.

 

As for the fuse, I was advised by Humminbird to put one in, can't hurt, going without could. The choice is yours.

 

SM

[darnsarf]

The Lowrance units from JK Max are supplied with a 3 amp inline fuse. Like SM not an electrician but guessing they are supplying for a reason.

[Patrick Pending]

Hi Martin,

 

Charging SLA's (sealed lead acid) batteries at to high a rate can reduce their capacity to hold charge and seriously shorten their life. As Starvin says get the right charger .

 

With regard to the fuse you definitely don't need one! That is, until you definitely need one! - a bit like a PFD on a yak, a total waste of time until something goes wrong and your thrown into the sea! - then they suddenly become useful .

 

I have in the past accidently blown up a large lead-acid battery it makes quite a bang and sprays sulphuric acid and bits of battery casing over quite a large area I was really embarassed at my mistake and got a right b****cking off my boss at the time. However, he then did exactly the same thing just the following week and the workshop got a second coat of acid .

 

I have also witnessed a couple of electrical fires caused by shorts from lead-acid batteries that were not appropriately fitted with a fuse. I don't think that would be a good thing to happen on a plastic yak at sea

 

"a reputable dealer who advised", there seems to be no area of expertise that retailers won't give wrong advice on !

 

BTW Although I often get it wrong myself, I do have a B.eng. in Electronic Engineering so I am at least qualified to get it wrong in this area

[phooey]

Hi Martin,

 

Charging SLA's (sealed lead acid) batteries at to high a rate can reduce their capacity to hold charge and seriously shorten their life. As Starvin says get the right charger .

 

I have a Halfords 'Fully Automatic' battery charger.

 

It only charges 12v but has modes for Car or Motorcycle batteries, Liquid acid or Gel types and it specifically states it safeguards against overcharging.

 

£25 or thereabouts I think

[terry1956]

Hi look on maplins site, you will find the correct charger, its around 19 pounds, will charge 3.3 AH batterys and up to 24 volt, its auto so just plug and play. DO NOT CONECT TO CAR BATTERY CHARGER. will kill the battery.

One thing with the maplins site, the prices are plus VAT.

TERRY

[Martin Hurst]

thanks everyone , all we need now is some sun

[Martin Hurst]

Maplins £12.99 Bargain!

 

12V Sealed Lead-Acid Battery Charger

 

a plug-in charger suitable for 12v sealed lead-acid type batteries up to 9ah. connect the leads to the battery terminal and the led lights to show correct charging....

 

LL30H 12V 350mA SLA Crgr 14 in Stock £12.99

[phooey]

Hi look on maplins site, you will find the correct charger, its around 19 pounds, will charge 3.3 AH batterys and up to 24 volt, its auto so just plug and play. DO NOT CONECT TO CAR BATTERY CHARGER. will kill the battery.

 

 

Noted - but as I'm using a motorcycle battery I reckon I should be ok

[ColinW]

I've never tried it but it seems to me you could probably just plug your battery into the cigarette lighter socket in your car (make sure you get the polarity right!). Probably be charged up by the time you got home.