GBM wrote:
John,
Your example perhaps explains the reason for my question.

You are right - If I go to a windlass that draws 80 - 90A, I WOULD need
large cables.

I'm quite sure I've never drawn close to this current with my windlass.
You should understand that you will need the same number of watts of
power to hoist your anchor at a given speed- no matter which windlass
you choose. A larger capacity windlass 'just lazing along' will draw
the same current as (probably less than) a smaller one which is near
stalling.
(Out of interest, how did you conclude that your
advisor was right about the 1/0 wire?)

A trip on another boat with undersized wiring and problems, and no
problems with my installation. Positive comments on surveys. Great rep
of advisor.

Getting back to windlass choice: Why choose a windlass that draws such a
high current on a 30-32 ft boat? There are windlasses available that use
epicyclic (planetary) gears that are much more efficient.

I wanted a vertical axis windlass with rope/chain gypsy and rope
capstan above. There were limited choices. Current draw is not an
issue. I didn't want a flimsy unit from an unknown maker. There's not a
big difference in 'efficiency' between different motor designs for
windlasses. Compare speed of hoist and load (in N)- you will need the
same number of watts with any unit. There's no 'free lunch'. You are
trading speed of hoist, force and power consumption.

For example, a Quick Genius (similar specs to Concept 1) draws just 40A at
working load - Quick recommends 6AWG wire for a 50-60ft return trip. See:
http://www.1stopmarineshop.com/Quick%20Windlass.html . The Lofrans Dorado
has similar lower current draw. http://www.lofrans.it/english/intro.html
There are vertical units that are also efficient. Is there a downside to
using one of the higher efficiency units?


I think one of my main concerns has been answered - If I draw 80A for 5-10
min,
Well, one of the 'high efficiency' units may take 5-10 min to hoist the
anchor and rode, but I've never needed more than a couple of minutes to
pull in even 300 ft of rode and anchor.

A couple of ammeters in your system will open your eyes to the actual
situation- put one in the charging line and another on the load side.
You will be amazed how little current is produced by your alternator
(without an external over-ride regulator). A couple of reading lights
left on for the evening will pull more energy from your battery bank
than hoisting your anchor with your new windlass.

So many choices, so little cash!

Cheers
John

"John" wrote

Well, one of the 'high efficiency' units may take 5-10 min to hoist the
anchor and rode, but I've never needed more than a couple of minutes to
pull in even 300 ft of rode and anchor.

John - If you compare specs and read the tests/reviews, you will find that
some windlasses do consume less power for the same working load and speed.
Here is some data from the manufacturer's literature comparing the Lewmar
Concept 1 with a Quick Genius 600 (admittedly quite different windlasses):


Working load:- Quick: 85Kg Lewmar 45Kg (seems
low?)
Maximum pull:- Quick:680Kg Lewmar 650Kg
Speed at working load:- Quick: 44ft/min @ 85kg Lewmar: 46ft/min
@ 45kg
Current draw at working load: Quick: 40A Lewmar: 80A

This is not a Lewmar vs Quick thing. Even within the same company, there are
efficiency differences. I have looked at many windlasses that would suit my
boat (using 3X ground tackle weight) and found large discepancies in power
and current usage. The Quick reps confirmed this and explained that it was
due to lower losses in the gearing of some newer designs - Power required
can be 30-50% less for the same load, even if speed is comparable.

Everyone has their own take on these things, but mine is to put in the most
efficient unit that will do the job. This is partly driven by limited
engine HP which limits alternator size, which limits battery bank capacity.
It is also driven by keeping weight and dollars invested to a minimum

GBM




A couple of ammeters in your system will open your eyes to the actual
situation- put one in the charging line and another on the load side.
You will be amazed how little current is produced by your alternator
(without an external over-ride regulator). A couple of reading lights
left on for the evening will pull more energy from your battery bank
than hoisting your anchor with your new windlass.

So many choices, so little cash!

Cheers
John