What size battery?

[Travis]

We have a Genacis Dolphin M4 generator fitted to Travis. Its starter battery is charged by the generator itself. The handbook says a 40ah battery is adequate, but does anyone think the inbuilt charger would be good enough to keep a 110ah battery fully charged? I seem to remember years ago trying to charge a 110ah with a small car type battery charger,and it wouldn't touch it. Thoughts?

 

Andy

[chris w]

We have a Genacis Dolphin M4 generator fitted to Travis. Its starter battery is charged by the generator itself. The handbook says a 40ah battery is adequate, but does anyone think the inbuilt charger would be good enough to keep a 110ah battery fully charged? I seem to remember years ago trying to charge a 110ah with a small car type battery charger,and it wouldn't touch it. Thoughts?

 

Andy

 

Andy

 

If you use a gennie to charge a domestic battery don't use the DC output. Use the gennie to run a mains powered multistage charger. If the battery to which you refer however is just a starting battery then almost anything will charge it as to start an engine takes about 1AH only.

 

Chris

[Travis]

Cheers Chris,

 

Yes we have a multistage charger, a Mastervolt Mass 24/50, this keeps the main battery bank charged via the line or the genny when we're not on our home mooring.

 

Its the actual inbuilt charger in the genny that keeps its own starter battery full that I'm wondering about. I cant find any reference to its output in the manual. How could I check its output when I cant run the genny without the battery connected.

 

Andy.

Edited March 24, 2008 by Travis

[chris w]

Cheers Chris,

 

Yes we have a multistage charger, a Mastervolt Mass 24/50, this keeps the main battery bank charged via the line or the genny when we're not on our home mooring.

 

Its the actual inbuilt charger in the genny that keeps its own starter battery full that I'm wondering about. I cant find any reference to its output in the manual. How could I check its output when I cant run the genny without the battery connected.

 

Andy.

 

The gennie's own charger will not be a sophisticated multistage jobbie. It'll just be a simple low curent constant voltage charger. The gennie batery is just a starter battery. I would forget it IMHO.

 

Chris

[Travis]

Chris,

 

OK I'll own up..the genny wouldn't start this morning. Wen uses it when she uses the washing machine or dryer. It's to keep the boat clubs electricity bill down.

 

Today it wouldn't have it, the battery was almost flat as a f*rt. I jumped it from the main engine battery and am considering putting permanent cables instead of the jump leads. I reckon the engine alternator will keep both batteries charged. The genny battery is a year old, levels OK and theres no loose cables anywhere.

 

Andy.

[blackrose]

Chris,

 

OK I'll own up..the genny wouldn't start this morning. Wen uses it when she uses the washing machine or dryer. It's to keep the boat clubs electricity bill down.

 

Today it wouldn't have it, the battery was almost flat as a f*rt. I jumped it from the main engine battery and am considering putting permanent cables instead of the jump leads. I reckon the engine alternator will keep both batteries charged. The genny battery is a year old, levels OK and theres no loose cables anywhere.

 

Andy.

 

I have a Honda EU30i petrol generator with electric start and the motorcycle-type battery went dead. Your battery sounds bigger then mine but you could just connect a cheap motorbike battery charger to it while you're on shore power to keep it maintained. Not sure if this one has a big enough output for your generator battery but there are others in the range.

 

http://www.mynewcheap.co.uk/products/detai...y-charger/2230/

http://www.active-robots.com/products/powe...s800-manual.pdf

[Travis]

Aye Mike,

 

the genny uses a Farymann diesel engine, only about 290cc, its tiny. Its an inbuilt, cocoonned jobbie by the way.

 

The battery is fairly new, I fitted last year when the previous one went the same way. TBH I dont think the genny is keeping its own starter battery charged, if its charging at all. The genny is not used that much, probably only run once a week, 420 hours/ 4 years from new. Thats the reason I thought about keeping it charged via the engine alternator, Ive already made the leads up and am trying to deciding wether to get up and fit 'em or watch Waterworld on the telly. (Or go to the Anchor for a last drink before w*rk tomorrow)

 

Andy.

[BigRoj]

TBH Andy, I'd be inclined to do away with the Gennys battery and charger and run cables straight from the main engine starter battery. If it's an inbuilt unit as you say and not likely to be shifted, it will add to it's starting reliability and take away the uncertainty of the gennys own charger.

[Travis]

Yep, you made up my mind for me Roj, I'll do that.

 

Thanks all for your help.

 

Andy.