batteries and switches
 

Should I put in 1 or 2 batteries for my 20’ sceptre? I would really like to only have one, but would like your opinions as to why a may need two, or is one really enough.

Secondly, Do I need a battery shut off switch? Is this just a safety device if something goes wrong like an electrical fire, or does it isolate stray currents or what ever when not in use? The boat will be on a mooring.

Thanks.

Re: batteries and switches
 

A second battery sure helps to start the engine when one is dead.

SOME electronics drain minute amounts of current when not in use (electronic clocks, some GPS memory cards, etc).

Redundancy is a good thing with batteries, bilge pumps, communication methods, and a host of other things on boats...

Re: batteries and switches
 

Jim, I am a fan of two batteries. It's not much fun when your out at night and you realize your altinator doesn't work and your about to get sucked into the breakers, you can't seem'em but you sure can hear'em when you get about ten yards away.
I'll never forget that night. The three of us on board all had the same blank look of "OH SHIT" when I turned the key and nothing happened, then smiles when I switched batteries (quickly) and she turned over.

Re: batteries and switches
 

I would go with two batterys. If you do go with one I would go with a dual purpose battery. This is a cranking and deep cycle battery all in one. A battery switch is nice due to if you leave something one it will be turned off when you turn the switch off. Be sure you wire it so you float switch stays hot all the time. THe best way to go is have two batterys. One a cranking battery for the engine the second a deep cycle for all equipment. In a 20ft boat two batterys is overkill but its well worth the first time you need it.

Re: batteries and switches
 

"..In a 20ft boat two batterys is overkill..."

I don't see where length of boat has much to do with it. I have just as much in the way of electronics on an 18' as many people with a 28'. There have been many occasions when the second battery was a welcome addition. A given electrical instrument will drain the same amount of juice from a battery whether it is mounted in a rowboat or in a 65ft sportfisher.

I like being able to listen to the stereo with just one battery feeding into the system knowing that if it gets low the second battery will fire up the engine and get me home. Overcautious? maybe, but the music sounds better that way.

Re: batteries and switches
 

Ebeach go for two, I have two dual purpose and a good swtich between them. I run one one trip and the other the next, back and forth so they get equal use and have a good charge on them. nice to have and not a huge cost to get done [img]images/icons/grin.gif[/img]

Re: batteries and switches
 

Just bought a couple of those Optima batteries. Any of you guys used them before?

Re: batteries and switches
 

OK, two batteries it is! Not a problem with the cost, more of a concern with weight and space. That will take care of the switch question too.

Gold or copper wire? Let me guess, gold. [img]images/icons/grin.gif[/img]

But seriously, does marine grade really mean much? Can't I just go to the electronics store and get wire? I'm also thinking toggle switches with rubber boots. Comments?

Re: batteries and switches
 

Optima batterys can not take the charging system of a outboard. Its ok for sterndrive and inboard use. There is normally more items on a 28ft vrs a 2ft. There a normally 3 large pumps, cabin lights some have a fridge that runs off of 12 volts along with all kinds of water system pumps. Thats the reason why I said for a 20 its overkill. I have a 20 cc and am running two batteries just to play safe.

Re: batteries and switches
 

The battery box in my 20CC won't hold 2 batteries. I've got one dual purpose battery that's used, and a fully charged "back up" in the console. As for a switch, IMHO it's another point of failure (corrosion). I use the "quick connect" battery cable terminations versus the wing nuts.

[ May 28, 2003, 08:41 AM: Message edited by: Honey Hole ]

Re: batteries and switches
 

Jim,
I'm not quite there yet on my boat but I was thinking about moving the batts into the forward storage areas of the split console on either side with a switch somewhere in the drivers side bulkhead. I did the same thing in the 23 but put both batts on the same side of the boat.It gets some weight out of the back of the boat and condenses all of the wiring. The hardest thing is running the Engines batt cable all the way forward, its usually too short from the factand has to be lengthened.
As far as marine grade wire, its a must. You are operating direct current, not alternating. Direct current produces more heat and requires much heavier wire as wiring distance increases. Store bought house wiring will not hold up to DC and could possibly melt and cause fire.
I'm not an electrician, but I did stay at a holliday inn express last night.

Re: batteries and switches
 

"I'm not an electrician, but I did stay at a holliday inn express last night. "

OUTSTANDING [img]images/icons/grin.gif[/img]

Re: batteries and switches
 

The main difference is that marine grade wire comes tinned the whole length of the wire where regular wire/auto-store/wally world wire of the same type is not and will corrode much faster(almost immediatly if your boat stays in the water like mine. The tinned wire will also solder much better for those who like to solder there connections,although I dont like to solder my connections as they can break easier with jolts/jarring etc. as opposed to properly crimped,liquid electrical taped , etc. I didnt stay at a holiday inn express but I did hang out at a 7-11 !

Re: batteries and switches
 

70’s, Thanks for your input. I too had thought about moving the batteries up front, but I’m a bit concerned about the amount of pounding they would take that far forward. Not to mention, that’s really the only decent storage on the whole boat. Is your fish boxed closed off from the console storage?

Miles, are you saying you’ve been there done that with SAE wire? I would think that automotive wire would work fine as long as you tin the ends and use shrink wrap on your connectors. (?)

Re: batteries and switches
 

Having just have to replace the 1/0 welding cable, that was my battery cable, as suggested by the marine surveyor for a insurance valuation, in my Hatteras with marine grade wire, I would suggest that after all the time and money spent on these boats why put the cheap wire back in?
The marine grade wire insulation is thicker and will withstand the water and salt much better.
I personally use all marine grade wire, with the heat shrink terminal end and put dielectric grease on anything exposed, terminal blocks, ring fittings, etc.
As my daddy used to say, There are no mechanics offshore when she breaks.
22cents worth.

Re: batteries and switches
 

Always go with Marine grade tinned wire and then go up a size in case you add to the load later, go with 2 batterys (one crank/one deep cycle for accessories) and switch and a direct hot lead to the bilge pump switch as already noted, and though I did not stay at a holiday inn express or hang at a 7/11, I did get an Italian sub at a Quick Check with hot peppers and then took the rest of the day off...

Re: batteries and switches
 

I agree with 2 batteries regardless of boat size unless you can paddle it or have a pull start kicker.

You don't have to stay at a Holiday Inn Express to know that, but I did take a dump at McDonalds in San Francisco yesterday...

Re: batteries and switches
 

Now thats funny! [img]images/icons/grin.gif[/img]

Re: batteries and switches
 

and true...