In article ,
Chuck Cox wrote:

Having read postings here about cruisers running with reduced radar and
lighting at night in order to conserve battery power, it occured to me
that we could repackage the charger for marine use. It would be roughly
shoe-box sized and effectively silent unless you were sitting next to it
on a calm day. It seems like this would be useful for boats with no
genset and modest electrical loads (i.e. lights & electronics). When
connected to the battery it would automatically start up and and shut
down as necessary to maintain the charge. It could also be designed to
cooperate with external charge controllers.

About the only candidates I've seen have inefficient AC/DC refrigerators
in small boats. Those with onboard A/C might find it undersized. At
that, you could have sufficient market, though 500w would be huge
overkill.

In rough numbers, to effectively consume that much power, the boat would
have at least 500 AH capacity. My 55 amp charger rarely runs as high as
20 amps for a few minutes on our 250 AH system. Even the smart charger
doesn't stay that high for much longer.

And it can only be used on the deck unless it's set up to be sparkless
and the exhaust can be piped away from the interior, which eliminates
much of the cruising crowd.

--
Jere Lull
Xan-a-Deux ('73 Tanzer 28 #4 out of Tolchester, MD)
Xan's Pages: http://members.dca.net/jerelull/X-Main.html
Our BVI FAQs (290+ pics) http://homepage.mac.com/jerelull/BVI/

Jere Lull wrote:

In rough numbers, to effectively consume that much power, the boat would
have at least 500 AH capacity. My 55 amp charger rarely runs as high as
20 amps for a few minutes on our 250 AH system. Even the smart charger
doesn't stay that high for much longer.

That's not my experience. I have 4 Trojan 6 Volts, for about 450 Amp
Hours. My charge rate starts at over 100 Amps and spends a lot of
time (close to an hour) over 80. When I get over 80% full the rate
drops fairly fast and I shut it down below before it goes below 50
Amps. I'd rather run 5 minutes tomorrow than 10 today.

If you're only charging at 20 Amps then either you're not very
discharged, or the alternator or regulator is not pushing very hard.


And it can only be used on the deck unless it's set up to be sparkless
and the exhaust can be piped away from the interior, which eliminates
much of the cruising crowd.

Certainly if its automatic, a number of precautions must be taken. I
would use a small genset on deck rather than run the engine, if it
could actually charge at 80 Amps.

Jere Lull wrote:
In article ,
Chuck Cox wrote:


Having read postings here about cruisers running with reduced radar and
lighting at night in order to conserve battery power, it occured to me
that we could repackage the charger for marine use. It would be roughly
shoe-box sized and effectively silent unless you were sitting next to it
on a calm day. It seems like this would be useful for boats with no
genset and modest electrical loads (i.e. lights & electronics). When
connected to the battery it would automatically start up and and shut
down as necessary to maintain the charge. It could also be designed to
cooperate with external charge controllers.


About the only candidates I've seen have inefficient AC/DC refrigerators
in small boats. Those with onboard A/C might find it undersized. At
that, you could have sufficient market, though 500w would be huge
overkill.

In rough numbers, to effectively consume that much power, the boat would
have at least 500 AH capacity. My 55 amp charger rarely runs as high as
20 amps for a few minutes on our 250 AH system. Even the smart charger
doesn't stay that high for much longer.

And it can only be used on the deck unless it's set up to be sparkless
and the exhaust can be piped away from the interior, which eliminates
much of the cruising crowd.


To protect bilge pump power, I'd put one in the forepeak, hooked to
a cell phone modem voicemessage to automatically call me and let me
know the boat in Bermuda, wherever, needs attention from the marina guy.

It also sounds good for camping, and recharging a battery for the
trolling motor on a CL 16 in the bush, oe even a canoe, IF it had a
manual - auto start off switch. I'd float the thing in a cooler on
a long string if neccessary on a rainy weekend spent under a boom tent.

Sailing is a way to get away, you see, and take it all with you.

Sounds like a great backup for any power, short of the ship's
elevator. Could even recover from a flat starting battery for a
diesel too big to hand crank.

Any gentleman would love to find one in his stocking.

Price? I saw something like that, as big as a bladeless chainsaw,
at CTC for not much.

Terry K