Thread: New Batteries?
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cavelamb himself[_4_] cavelamb himself[_4_] is offline
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First recorded activity by BoatBanter: Aug 2007
Posts: 383
Default New Batteries?

Larry wrote:


http://www.harborfreight.com/cpi/cta...emnumber=45416

10KVA peak for starting, 7.2KVA continuous duty for running... on sale
for $299. 120/240, single phase AC. To get 3600 RPM means to get 60 Hz.
You'll need to UP convert torque into speed at your economical cruise RPM
of the main engine with enough parallel V-belts to handle 20HP, typically
2 but 4 will last lots longer. The output is electronic regulated to
120/240VAC inside the box on the back of the self-starting alternator.
No external source is necessary to start it.

These Chinese make a beautiful machine for such a cheap price at Harbor
Freight. Turn it with your hand. Its ball bearings are as smooth as
silk and as tight as a finely machined watch. It's extremely well
balanced.

If you're running the engine on a power boat at a relatively constant
cruising speed, no sense running another 2 or 3 conversion inefficiencies
when you can have real AC right off your belt drives. Simply shut down
the loads before going into any situation where you must vary the RPM of
the main engines, greatly. An extra 20hp load on them won't make that
much difference to their already-terrible fuel mileage.....

Every time I turn one of these, I wanna see a 1:2 or 1:3 pulley ratio
turning it up 3600 RPM from a 1800 or 1200 RPM 3 cylinder Yanmar in a
quiet cabinet. 10KW is a LOT of power!

BIG DISCOUNT IN PRICE for the last year or so!

Larry



Hey Larry,

That hummer looks interesting.

But...

Forgetting to disconnect the electrical load before throttling could
make a mess of those expensive electronics.

Sounds like the perfect job for a PIC or BASIC Stamp?
Monitor RPM and dump the electrics if too high or low.

Richard