Battery charging ???

[PhilfromOhio]

Hey everyone... PhilfromOhio here, I am putting the finishing touches on my
1958 V4S-10 50Hp. Mine is not equipped with a generator. I am thinking that since all the battery operates is a bow and stern light and the ocassional radio, I could get by with a 15ah solar generator? So long as I plug it in at the start of the fishing day, and my batteries are new, yes I said batteries, using 2 brand new marine batts daisy chained together. That old gal drinks the power when starting? I havent had it in the water yet, but I think the 15ah solar panel will be a good trade off. I have heard that the generator is a Horsepower drain anyway? I need all of your opinions on this one.... thanks guys....

 

[F_R]

Re: Battery charging ???

Hey everyone... PhilfromOhio here, I am putting the finishing touches on my
1958 V4S-10 50Hp. Mine is not equipped with a generator. I am thinking that since all the battery operates is a bow and stern light and the ocassional radio, I could get by with a 15ah solar generator? So long as I plug it in at the start of the fishing day, and my batteries are new, yes I said batteries, using 2 brand new marine batts daisy chained together. That old gal drinks the power when starting? I havent had it in the water yet, but I think the 15ah solar panel will be a good trade off. I have heard that the generator is a Horsepower drain anyway? I need all of your opinions on this one.... thanks guys....

90% of them never had generators and had no problem with only one battery. What you are proposing is plenty adequate and probably even overkill. Unless you do an unusual amount of starting and stopping. Hey, we did a lot of starting and stopping while water skiing.

As for the generator being a horsepower drain, of course that is true because there is no such thing as a free lunch. But I'll guarantee that you would never notice the difference. Hm.m.m., come to think of it, a solar charger would be a free lunch---after it is paid for.

 

[PhilfromOhio]

Re: Battery charging ???

I didnt know that about not being standard equipment. I ran a multimeter on it during the harness rebuild, it draws about +80ah every time it starts. I know it seems a bit like overkill, but we like to do a lot of night trolling, plus even though I have restored 75% of the motor, there still exists a chance of having to troll motor her back in should the old fat fifty start acting up. Thanks for the note F R...

 

[Silvertip]

Re: Battery charging ???

A 15 Ahr solar panel is one heck of a panel -- likely half the size of your boat. Do you mean 15 watts perhaps? If that's the case, the panel outputs a little over 1 amp which would take several days to top off a deeply discharged battery much less two of them. If you really do have a 15 A/hr panel you paid more for it than a small generator costs that would charge the batteries a heck of a lot faster.

 

[Vic.S]

Re: Battery charging ???

A 15 Ahr solar panel is one heck of a panel -- likely half the size of your boat. Do you mean 15 watts perhaps? If that's the case, the panel outputs a little over 1 amp which would take several days to top off a deeply discharged battery much less two of them. If you really do have a 15 A/hr panel you paid more for it than a small generator costs that would charge the batteries a heck of a lot faster.

You cannot rate a solar panel in Ah, that's the unit for battery capacity!

You could rate a panel in amps (A) but it is usual to rate them in watts.

They are rated at their maximum power output which is usually at a terminal volts of about 16 V, so in practice you don't get the full rated power when battery charging. Close to it if you have a "maximum power point tracking" (MPPT) regulator perhaps.

It is a rule of thumb that over 1 watt per 10Ah of battery capacity requires a regulator and also generally advised that solar panels over 10watts should have a regulator anyway.

A 15 watt solar panel would probably have an overall area of something like 3 sq ft.

A solar panel for battery charging requires a blocking diode to prevent a loss through the panel during darkness. Often the diode is built in to the panel or will be part of the regulator circuit

 

[emdsapmgr]

Re: Battery charging ???

I ran a fat 50 for years. Never had a charger on it. Since it was only used for starting, I could charge the battery up every month or two and it always ran fine through the summer months. That engine has a nice factory hand rewind starter behind the front cowling cover. If you ever run out of battery power, you can pull start it.

 

[PhilfromOhio]

Re: Battery charging ???

The solar charger I am thinking of using is a 15watt, sold at Harborfreight. It is 12"X36" I built a pretty cool bracket that clamps on in the back of the boat that I was going to use once I got to the fishing spot. Just put it out and let her go. I'll hold off and see what happens the first couple of trips. I do have a pretty decent portable power pack good for starting dead batteries. However mine are brand new, just picked them up at Sears, 79 bucks each. I keep them on a trickle charger now since its still pretty cold out here. I guess basically I am trying to find out the best way to ensure they dont fizzle out on me when i am out on the lakes. I would go with the generator, but they seem to be impossible to find.

 

[Vic.S]

Re: Battery charging ???

Small solar panels really come into their own if you leave them charging the battery via a regulator while you are away from the boat.

I only have a 5 watt solar panel but it is permanently connected and tops the battery up while the boat is not in use. Not had to remove the battery for charging since I fitted it. Previously with only a small outboard providing a little bit of power I used to have to take the battery home periodically for charging.

No electric starting but the battery powers cabin lights, navigation lights, VHF RT, echosounder and autopilot on a small sail boat.

Remember it is bad for batteries to leave them in a discharged or even partially discharged state.