On Jul 16, 7:53*am, "
wrote:
Hi, thank you for entertaining my humble question.

I plan a near permanent 240v from land on my liveaboard, but
it has just had normal 12v engine battery put in.

Ideally, the finished system would be 12v *or 24v based, with clever
240v trickle charger (i dont know what its called but it keeps 12v
topped up).

The reason for mixed system, is that the 12/24v 'bus' will take wind/
solar much better than than the 240v. At the moment its non-connected
240v/12v, but all the lights are 12v, stepped down
to 12v maplins styley, so why not bus it mostly 12v/24v dc?

Yours in stupidity,

Nick Macro
serendipity, newhaven, brighton uk

pps. bilge pumps heeeeeellllllpppppppp

Be very careful using mains land voltage (240 volts) aboard the boat.
Not so much for safety, although that IS a very serious issue; leakage
from your boat could endanger a swimmer in the water.

But also because boats connected to land systems, without an isolating
transformer, especially on a long term basis, can suffer electrical
leakage that causes corrosion of metal parts of the boat that are in
the water. New bronze or stainless props. can be expensive also metal
fittings in boat hull can be corroded and then later, leak. (And sink
boat?).

Quite a complicated subject!

If you use a hefty 240 to 12/24 volt power supply or smart/charger it
may or may not 'isolate' the boat's electrical grounding system from
the shore power. For example if the shore power is not well grounded/
earthed, it and every other boat in the marina, may, quite
inadvertently since plugged in all the time, find that your boat is
the best ground around. And in days your boat's metal parts may
dissolve in bubbles!!!! Just think of it as very quick electrolytic
rusting!

Get good advice. Somewhere I have copy or link to a good, but
complicated article that covers the subject. Will try and find and
list on this news group for info.