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Ed Ed is offline
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First recorded activity by BoatBanter: Jul 2006
Posts: 97
Default Alternator size vs Windlass current

They will not draw full amperage if used properly. use your engine NOT
your windlass to move the boat over the anchor. The most stress your
windlass should ever have is lifting the anchor, chain and rode. it
should not be used to free an anchor (Except min mud etc)

I have the Lofrans 1000 Watt (1000/12 = 83 Amps... 2 group 31s in parr
can handle that + 50 amp DC charger + alternator) (Marlin maybe... not
sure of the model). I only have an issue if I disobey my own rule...

Size the windlass to about 2x the weight of the anchor, chain and rode
and you should be fine. mine is supposed to be for a boat up to 40' and
I have run a 48' 50K LB boat with it for 5 years including LOTS of
diving on 130' deep spots (300'Rode, 40' BBB chain, Steel danforth)
BTW... I love the combo lofrans.... chain/rode gypsy + a capstan you can
disconnect and use for the second anchor or dock lines.




GBM wrote:

I am still trying to decide on a windlass for our boat. Perhaps some the
experienced cruisers can help?

Our alternator output, is nominally 55A, but likely actually quite a bit
less. Max size alternator recommended for Yanmar 2QM15 engine is about 80A)

Some suitable horizontal windlasses for a 32 ft boat draw as much as 90A
(e.g. Quick Eagle 500/700)

If we have the engine running at say 1500rpm while pulling up the anchor, we
may be putting about 35A into the 200AH house bank, if we are lucky. At the
same time, the windlass is drawing up to 90A and other items like the refrig
unit are still drawing current. We could have a shortfall of 60A for 5-10
minutes.

Question: Would I be better to buy a somewhat undersized windlass that might
only draw 35A? (e.g Lofrans Dorado with gypsy on wrong side ) or buy the
larger unit and draw a bigger current?

GBM

(PS: I have 6 Ga wiring already installed, but will change if need be)