On 19 Oct 2005 17:08:33 -0700, "Matt"
wrote:

Hi,
I'm looking at installing a 30 watt solar panel\on my boat. I'd like
to charge both the starter and domestic batteries. Can anyone give me
some ideas on how I'd wire a setup like this. Also I have a regulator
which is used for a 240 volt charger. Will I need a seperate regulator
for the solar panel?

Cheers

Consider a MPPT-charger to get the most out of your panel. It depends
on where you are but eff can go up with 30%.
Instead of the switchboard you described (which still leaves the risk
of enormous equalizing-currents when one batt is full and the other is
empty and in that situation you bridge/connect them) I'd consider a
FET-based battery-isolator. Old fashioned diodes cause a voltage loss
of 0,7v which prevents full charging of your battery. The voltage drop
these FET-isolator cause can be neglected.
I'm in the Netherlands so I use european url's, sorry bout that.
http://www.victronenergy.com/productlist.php
for mppt-chargers:
http://www.dbcom.nl/mste.htm
You won't have much trouble finding similar products in the us I
guess.

HTH
Len,
S/v Present

"Instead of the switchboard you described (which still leaves the risk
of enormous equalizing-currents when one batt is full and the other is
empty and in that situation you bridge/connect them)"

re quote above: That's a worry as very often that's been the case .
I'll make sure I dont bridge them in the future. Would this also be the
case with the common battery isolator switches with a "1", "2", or
"Off" position? or have I got my wires crossed. hehe

I'm in Queensland, Australia. Lots of Sunshine. Don't know anything
about MPPT chargers.

Connecting directly to the house battery sounds like a good idea and
would certainly simplify things.

Thanks all.

"Matt" wrote in message
oups.com...
"Instead of the switchboard you described (which still leaves the risk
of enormous equalizing-currents when one batt is full and the other is
empty and in that situation you bridge/connect them)"

re quote above: That's a worry as very often that's been the case .
I'll make sure I dont bridge them in the future. Would this also be the
case with the common battery isolator switches with a "1", "2", or
"Off" position? or have I got my wires crossed. hehe

Yes, the 1-2-both switch has the same potential problems. Best to eliminate
it altogether.

I'm in Queensland, Australia. Lots of Sunshine. Don't know anything
about MPPT chargers.

Not sure what one has to do with the other. MPPT chargers are nice. They net
you a bit more out of your panels. Typical cruising it only 5% or so. The
big
claims of 20% (never heard any claim of 30%) is when the batteries are low
and the panels are cold. But 5% is 5% and the MPPT controllers are not
all that expensive anymore. Check out www.solar-electric.com for a good
explaination of solar charge controllers.

Connecting directly to the house battery sounds like a good idea and
would certainly simplify things.

Thanks all.