Outsmarted myself....Doh!

[savage]

The other day I was starting the motors on my boat just to give them a run, Bugger one of the batteries is as flat as a maggot. So of to Supercheap for a new marine/deep cycle battery, I like to keep things even and equal so 2 new ones are bought, everything OK so far.

Read up on duel battery/duel motor applications in boats and decided I would re-wire the setup I already have, actually it's a small modification.

So I need extra battery cable, they only had black and I needed some red of equal size and length, rats!....I know, I'll buy a cheap set of jumper leads and fit them up for what I need.

Get home and decide to start, so chop the clamps/clips off the ends!......whoa!....these are supposed to be 100amp min leads, looked nice and heavy but the core inside is lucky to be that of the heavy earth used in house holds electrics. I think I just wasted $7.95, as I think it's too light for the permanent use I want it for.

[Termite]

Invest $60.00 in a 250mA solar panel and $1.00 in a diode. Hook up to battery.......no more flat batteries and I get 6 years average out of a boat battery (Low maint type).

[savage]

Yeah!..I was thinking of that, I did buy a couple of cheapies a few years ago with limited success, the results where what you would expect for the price. I was looking at the SuperCheap version, the price ranged from $60-$160 the panel size difference was only minimal but the dearer one seemed to have a different solar cell technology. The principle is great and I'll probably go ahead with it as I have spent more in batteries than the cost of the panel, but what is (a) the principal of a diode (what does it do)?, and (b) where do I put it? (be nice now!).

[Iain]

Diode is a one way valve, so to speak, the current voltage can't sneak back out at night and into the panel flattening the battery.
Also there is a Zener diode which is a crude form of voltage regulation, placed across the + - it limits the voltage going into the battery, if it's only a small panel I really wouldn't worry about it.
Edit.
Forgot B....In line

Panel + to - diode + to Battery +
Use a diode 500ma or bigger to happily deal with the current the panel can deliver, heat sink if neccessary.
Circuit below, imagine the coil on the left is the panel, the top is positive, the block on the right is the battery, the top is positive.

[Auld Bassoon]

Just a note on the above>

If I recall, deep-cycle batteries are only really needed for "domestics", not if battery is used only for main engine start.

Solar panels are an inexpensive way to keep thge batteries charged. It might be a good idea to rig-up a light mesh covering a few cm above the panels to keep the blerry seagulls off though!

Cheers!

[Ashore]

Savage , if you just put red heat shrink over the black cable you have , may save you the problem of the jumper leads.
If you use the batteries for anything else like lights etc you can also get a cut out device from places like jay-car that isolates your batterie/s when they drop to a set voltage , leaving you with enough to get a start for the motor

[savage]

Thank guys... I'll have to digest this, and all of the info I have already gathered, :confused: and then get me a solar panel sit down and make a custom battery box, modify the rear seat and then go fishing....The hardest part is when I have to pull up anchor and come home!.... Bugger! I hate that part.....

[Auld Bassoon]

The hardest part is when I have to pull up anchor

Sailing in the I.O. a few years ago on a 72' ketch-rigged cruiser, we dropped "the hook" so that the ladies on board ( ) could have a civilised luncheon.

When we went to engage the electric capstan - it failed. As acting 'mate', guess who had to manually haul up rather more than 30 fathoms of 12mm (diameter of the rod which forms the links) chain, plus about 40 fathoms of 25mm polypropylene anchor rope, and the 45Kg CQR. Cor! One stuffed Basson let me tell you!

NB couldn't use the sailing winches because the owner was a bit 'precious' about them, and didn't want nasty old chain scuffing them up

[RETIRED]

Most solar panels these days have the diode fitted.

[Iain]

The one they are talking about is a little beastie which will only trickle charge, not the bloody great big beasts we are used to
I have one at home which is about 10" long by 2" wide and used to charge nicads, not power the bleeding washing machine.

[RETIRED]

Yeah, aware of that Iain and I think that some of those have the diodes fitted as well. Big ones are more fun though

[savage]

Geez...the way some of you are talking I could use wire trace hooked up to a solar panel and chuck a hook and prawn on the other end, bingo!..
Get a bite and then just turn on the juice!....ELECTRO-FISHING..

[Iain]

Whats the hook for

[savage]

Got'a stick the prawn onto something to attract the fish!.....

[Auld Bassoon]

Got'a stick the prawn onto something to attract the fish!.....

I thought that's what a barbie was for - to stick the prawns onto