Maxwell windlass questions

[s/v Jedi]

I have a Maxwell VWC3500 windlass with 12V motor. It has a breaker/disconnect with the number 135 printed on it.

Does anyone know if this is a 135A breaker? I think it acts on heat, is that correct? I am thinking of installing a Blue Sea Systems RBS remote battery switch in the negative battery connection to shut it off remotely and provide galvanic protection, while replacing the breaker/disconnect with a fuse. Would a Midi fuse work?

Also, I am considering to replace the motor with a 24V model. Does anyone have a good source for these?

Thanks!

[a64pilot]

My 2500 has a 135 amp CB, and I believe we have the same motor (1200 W, 100 amps) even though of course you can raise 1000 lbs more than I, I assume due to different gearing and of course a stronger windlass.
Yes it’s a thermal breaker, works off of heat build up.
CB or fuse is irrelevant, so long as it’s circuit protected, I like a CB because I leave it open except when using the windlass to prevent it from operating on its own due to a shorted relay or something. A fuse would be more of a pain to disable.

Why not leave the CB? If the CB is open, how can you get stray current?

[s/v Jedi]

Originally Posted by a64pilot

My 2500 has a 135 amp CB, and I believe we have the same motor (1200 W, 100 amps) even though of course you can raise 1000 lbs more than I, I assume due to different gearing and of course a stronger windlass.
Yes it’s a thermal breaker, works off of heat build up.
CB or fuse is irrelevant, so long as it’s circuit protected, I like a CB because I leave it open except when using the windlass to prevent it from operating on its own due to a shorted relay or something. A fuse would be more of a pain to disable.

Why not leave the CB? If the CB is open, how can you get stray current?

A thermal breaker is slow... fuses like Midi fuses are fast...

There are two reasons for my change: I want a remotely operated switch so that I can switch it on/off from a location that is fast and convenient instead of going inside to the physical breaker. This is what the Blue Sea RBS allows. Also, even though the Maxwell has the battery negative insulated from the metal housing, I prefer to switch the negative to add another layer of protection. I have seen too much damage on anchor chains etc.
Also, the breaker I have is getting pretty old and I’m not confident it’s still protecting or if it will trigger too soon while I’m trying to get the anchor up during a storm etc. Then when I switch to 24V, do I go to a lower amperage rating or just stay at 135A to protect the wiring...

I saw some motors on FisherySupply for just over $500... not sure if they fit my windlass though.

[a64pilot]

Thermal breaker is slow, usually that’s thought of as an advantage as they can handle surges, as of course both the wiring and the motor can too.
Nothing at all wrong with switching the neg too if you want to and leave the breaker in place.
You have it correct, most often the breaker is a wiring protective device and is not there to protect the equipment. As you won’t be changing to smaller wire I’m sure, I’d leave the CB

[Reefmagnet]

Circuit breakers can be very twitchy when it comes to tripping at the drop of a hat (it depends on the breaker) and can get a bit sensitive the more times they trip whereas fuses never get that opportunity. If this was a problem in your case, you'd already know about it. This might not apply in your situation, but wouldn't the solenoid box provide isolation to the winch motor already?

[a64pilot]

Internet is in and out here, but I know this is not the right answer, but I’d be surprised if the motor wouldn’t handle 24V. I’ve converted a few old Ford farm tractors etc to 12V and leave the 6V starter and they work fine for decades.

Not sure this is your motor but a Google of Maxwell 1200W 24V motor comes uo with quite a few hits
https://www.hodgesmarine.com/maxp120...le-flange.html

Circuit breakers do take time to trip, if you look at this Diagram you can see they can handle 200% rated current for 20 sec or so before they trip, this is usually considered an advantage as if the wire is correctly sized, it can handle far more than that and a CB is a wire protection device, by allowing more than rated current you don’t get nuisance trips by stalling a motor etc.

https://www.bluesea.com/products/704...nel_Mount_135A

Slow blow fuses are of course, slow blow so they too can allow surges.
I just don’t like fuses, especially on something you may need in a hurry, cause finding and changing a fuse takes more time than resetting a CB.

Having said that I fuse my battery bank, but they are to protect the wiring of course, so they are BIG fuses, nothing should ever come close to pulling those kinds of amps on my boat, should take a direct short to get there and if that happened I want the circuit opened to prevent a fire. So fuses have their place.

[s/v Jedi]

Originally Posted by Reefmagnet

Circuit breakers can be very twitchy when it comes to tripping at the drop of a hat (it depends on the breaker) and can get a bit sensitive the more times they trip whereas fuses never get that opportunity. If this was a problem in your case, you'd already know about it. This might not apply in your situation, but wouldn't the solenoid box provide isolation to the winch motor already?

Yes but they age and mine is manufactured in 1993... It’s also a push-pull operated breaker which they stopped using... very dated.

The battery negative directly connects to the motor, there is no solenoid in that circuit. But the motor has an isolated negative.

[rslifkin]

For that same windlass in 24V, I think Maxwell suggests something in the range of an 80A breaker.

[s/v Jedi]

Originally Posted by a64pilot

Internet is in and out here, but I know this is not the right answer, but I’d be surprised if the motor wouldn’t handle 24V. I’ve converted a few old Ford farm tractors etc to 12V and leave the 6V starter and they work fine for decades.

Not sure this is your motor but a Google of Maxwell 1200W 24V motor comes uo with quite a few hits
https://www.hodgesmarine.com/maxp120...le-flange.html

Circuit breakers do take time to trip, if you look at this Diagram you can see they can handle 200% rated current for 20 sec or so before they trip, this is usually considered an advantage as if the wire is correctly sized, it can handle far more than that and a CB is a wire protection device, by allowing more than rated current you don’t get nuisance trips by stalling a motor etc.

https://www.bluesea.com/products/704...nel_Mount_135A

Slow blow fuses are of course, slow blow so they too can allow surges.
I just don’t like fuses, especially on something you may need in a hurry, cause finding and changing a fuse takes more time than resetting a CB.

Having said that I fuse my battery bank, but they are to protect the wiring of course, so they are BIG fuses, nothing should ever come close to pulling those kinds of amps on my boat, should take a direct short to get there and if that happened I want the circuit opened to prevent a fire. So fuses have their place.

You’re convincing me pretty quickly I think I will buy a new 135A thermal breaker and that motor you linked to. It is the P12074 while I need the P10157 but I just found it is a direct replacement...

[Wotname]

Originally Posted by s/v Jedi

A thermal breaker is slow... fuses like Midi fuses are fast...

.........

It is more likely to be a thermal magnetic breaker. The thermal aspects for for slow operation at small overloads while the magnetic aspects allow for fast tripping at high current overloads.

This is exactly what is needed for high current motors like the windlass. The motor can and will tolerate small amounts of excess current for short periods of time (say 30 seconds) and the breaker must be able to accommodate this. Long times of small overloads will overheat the motor and the breaker should trip before this occurs. However should a short occur, the breaker needs to act very fast to prevent very high currents flowing. A thermal magnetic breaker does exactly that.

The circuit breaker in an windlass circuit is designed to protect the motor and the wiring, not just the wiring so when you change to the 24V motor, change the circuit breaker to whatever rating the manufacturer of the motor suggests. Usually a 24V motor has considerably higher rated power output than the 12V motor so the circuit breaker may be around (say) 100A.

[s/v Jedi]

Originally Posted by rslifkin

For that same windlass in 24V, I think Maxwell suggests something in the range of an 80A breaker.

Yes, thank you! It’s hard to find but I just found the replacement part on an English Vetus website and it is 80A indeed

[s/v Jedi]

Originally Posted by Wotname

It is more likely to be a thermal magnetic breaker. The thermal aspects for for slow operation at small overloads while the magnetic aspects allow for fast tripping at high current overloads.

This is exactly what is needed for high current motors like the windlass. The motor can and will tolerate small amounts of excess current for short periods of time (say 30 seconds) and the breaker must be able to accommodate this. Long times of small overloads will overheat the motor and the breaker should trip before this occurs. However should a short occur, the breaker needs to act very fast to prevent very high currents flowing. A thermal magnetic breaker does exactly that.

The circuit breaker in an windlass circuit is designed to protect the motor and the wiring, not just the wiring so when you change to the 24V motor, change the circuit breaker to whatever rating the manufacturer of the motor suggests. Usually a 24V motor has considerably higher rated power output than the 12V motor so the circuit breaker may be around (say) 100A.

I found that behind their little plastic panel, they use a Bussmann thermal type III breaker. These cost $30 but with their plastic nameplate panel Maxwell seems to sell them for $130.

I will probably upgrade to a heavy duty version 80A, with both terminals at the bottom for easier cabling. These are sold by many brands incl. Blue Sea Systems.

Even though they are just thermal breakers, at current of 5x rated value they break in 0.1 second.

[rslifkin]

Those are the same breakers I use for high current stuff (including windlass) on my boat. Either the Bussmann 185 or 285 breakers (either direct or Blue Sea branded). The 187 series look nice as well, but I haven't used those.

[Manateeman]

Hi. The Maxwell 3500 with 24 volt motor came with Breaker number 185080P.
Fancy Maxwell plate. Sure is a necessary way to spend money. LOL.
Do you need the motor numbers?
Manatee

[Singularity]

Rote to say, but consider contacting Maxwell directly. When I wanted to convert my VWC1200 from 12 to 24v I contacted Maxwell directly and got the following instructions:

"You can convert a 12 volt unit to a 24 volt unit but you have to change the following parts

On/ Off Breaker ( new part number - P100791 )
Reversing Solenoid ( new part number SP5105)
And Motor ( new part number - P12074)

Best Regards

Will V.
Vetus Maxwell Inc.
714 227 38xx cell"
[convert the last two cell digits to "32" for the correct number]

I got these parts off Ebay for slightly less than Hodges, otherwise keeping the (functional) 12v stuff on board for backup.