12 volt windlass on 16 volt battery

[2nd Runway]

Hello
New here and My first post/question

I have a lewmar 12 volt pro fish 1000 horizontal windlass, a 32 volt house bank (several 16 volt batteries in series and parallel) that is within 5 feet of my windlass.

This is a li-ion battery bank and the voltage of each individual battery will never go above 16 volts.

I have also noticed that a lot of race car guys are using 16 volt batteries on 12 volt starters.

What is the consensus of running a 12 volt windlass on a 16 volt battery?
Will it harm the windlass motor or just make it run a little faster?

Your thoughts appreciated

[GordMay]

Greetings and welcome aboard the CF, Runway.

The Lewmar manual states: “The proper voltage on a 12 Volt system is 13.5 Volts, constant low voltage will damage motor.”
I’d expect your (nominal) 12V windlass motor to run a little faster, when powered by a 16V battery.
I wouldn’t expect it to damage the motor.
Pro-Series /Fish Windlasses Product manual ➥ https://ca.binnacle.com/pdf/Lewmar%2...0%20iss2_0.pdf

[smac999]

When you draw power from one side of the 32v bank how are you going to put the power back in? Charging at 32v will never rebalance those series batteries. This is why you never mid tap a battery bank.

You would need 16v chargers each charging the lower abd upper series bank. separately . Or an equalizer of some sort.

[GordMay]

Originally Posted by smac999

When you draw power from one side of the 32v bank how are you going to put the power back in? Charging at 32v will never rebalance those series batteries. This is why you never mid tap a battery bank.
You would need 16v chargers each charging the lower abd upper series bank. separately . Or an equalizer of some sort.

Indeed - asymmetrical loading is always problematic.

[2nd Runway]

Ok
I was under the understanding that the batteries would equalize.
I have a 10K watt-hour housebank that has been extremely reliable for several years and do not want to do anything to jeopardize that.
I think I will just get a stand-alone battery with its own standalone 12 volt charger to be on the safe side.
Thanks for the input.

[GordMay]

Originally Posted by 2nd Runway

Ok
I was under the understanding that the batteries would equalize.
I have a 10K watt-hour housebank that has been extremely reliable for several years and do not want to do anything to jeopardize that.
I think I will just get a stand-alone battery with its own standalone 12 volt charger to be on the safe side.
Thanks for the input.

Good idea.
Or, you could get a 24V windlass, and run it on your full 32V (nominal) battery bank.

[2nd Runway]

GordMay
When it’s time to replace windlass I will definitely consider that option!

[Paul L]

There are 100amp DC to DC converters that take 24v in, 12v out.

[BillKny]

Originally Posted by 2nd Runway

Hello
New here and My first post/question

I have a lewmar 12 volt pro fish 1000 horizontal windlass, a 32 volt house bank (several 16 volt batteries in series and parallel) that is within 5 feet of my windlass.

This is a li-ion battery bank and the voltage of each individual battery will never go above 16 volts.

I have also noticed that a lot of race car guys are using 16 volt batteries on 12 volt starters.

What is the consensus of running a 12 volt windlass on a 16 volt battery?
Will it harm the windlass motor or just make it run a little faster?

Your thoughts appreciated

Modeling what you do on what race car drivers do not a good plan. After all, if they had to replace a starter motor every 20 starts (about 40 seconds of total motor run time!) they would not care. You wouldn't even have your anchor up once.

Doing what you suggest is a bad idea for lots of reasons. As others have pointed out, center tapping a battery bank, especially with a big load like this is a TERRIBLE idea. But let's leave that---and look at the motor.

Just because other posters can not think of why this wouldn't work, doesn't mean it will.

Issue #1: Your motor's brushes will wear out in short order. The no-load speed of the motor will increase, and this increases the mechanical wear on the brushes, but also the higher voltage means longer lasting and more stable arcs every time the brushes move across a gap in the commutator, this is actually the bigger issue. Although this is a real problem, I seriously doubt the motor will last long enough to for you to notice.

The current draw of a DC motor is a complicated thing. When running "at speed" the motor generates a "back EMF" that reduces the current draw. So contrary to intuition, the faster the motor runs the less current it draws. This is why lower voltage is also an issue, the lower motor speed means more current.

So running at steady, no load speed, the motor will run faster at a higher voltage, and will draw about the same amount of current. It will run faster, but will produce no more torque. So, in a simplistic view of the world, the motor could run at the higher voltage and no load a long time without issue. But the world is not so simple.

So here is issue #2: The problem is when the motor is loaded up, even on startup. The higher voltage will cause it to draw more current, up to 30% more based on the voltage you propose. Since heat generated is proportional to current squared, the motor will generate 70% more heat than it was designed for in its windings when loaded, or when starting.

Since the average windlass motor is very poorly cooled, frequently starts and stops, and is frequently heavily loaded, I would predict a very short life from your motor windings. How short? I do not know know... maybe minutes? Maybe days? maybe if you find the actual motor manufacturer and ask?

It's a strange setup, such a small windlass on a boat with a 32 volt battery bank, but it is what it is...

[RaymondR]

Or you could use under sized cabling and let the increased series resistance take care of the problem for you.

[pcmm]

Originally Posted by 2nd Runway

Hello
New here and My first post/question

I have a lewmar 12 volt pro fish 1000 horizontal windlass, a 32 volt house bank (several 16 volt batteries in series and parallel) that is within 5 feet of my windlass.

This is a li-ion battery bank and the voltage of each individual battery will never go above 16 volts.

I have also noticed that a lot of race car guys are using 16 volt batteries on 12 volt starters.

What is the consensus of running a 12 volt windlass on a 16 volt battery?
Will it harm the windlass motor or just make it run a little faster?

Your thoughts appreciated

Where are you getting 16v batteries from? its such an oddball voltage? even with lifepo4 batteries

[mitiempo]

Originally Posted by pcmm

Where are you getting 16v batteries from? its such an oddball voltage? even with lifepo4 batteries

32 volt boat banks are typically composed of 8 volt batteries. 4 in series.

Not many 32 volt systems around any more. Most often found on older commercial boats and large cruisers from the 60's like some Chris Craft boats.

[jakkum]

I used a 12 volt dc dynamo wirh a bydraulic pump piggy back on it, ment for power steering of a lorry as a powerpack for steering my80 feet schooner.
No problem, only it was too slow and not powerfull enough. So I put it on tthe 24 volt system of the ship..
. Ow I do not know whether the lewmar motor is aa series motor like a startermotor or a parallel, like my 12 volt dynamo.
It came straight from yhe scrapyard and eas never deroced pm the ship

[Dirk01]

Originally Posted by RaymondR

Or you could use under sized cabling and let the increased series resistance take care of the problem for you.

Very good idea! Take 1.5mm2 and give them a sound burn in Put some windings back and forth and you can toast a whitebread at the same time you pull your anchor
This is quite as good as to pull current@16V out of a 32V housebank

So many so good ideas. I'm proud to be a member.

O.K., seems to be that I swollowed a clown
I appologize for my comments...

[Dirk01]

Originally Posted by pcmm

Where are you getting 16v batteries from? its such an oddball voltage? even with lifepo4 batteries

MN-based lithium batteries do have 4V (like the new Bosch-battery for mild hybrid cars @48V). But they schouldn't be used on boats due to their thermal runaway temp of around 700°C+ and their lack of intrinsic safety.

Hence, ensure not to have them. And flawless operation in the past is not a blank check for the future.

However, it is difficult to predict something, esp. about the future

(Sorry for my bad German school English - hopefully you got it even though)