VFD on a 110/220v anchor windlass

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Mako

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Does anyone have experience using a variable frequency drive on an 110/220v anchor windlass? It appears that a soft starter wouldn't work, but a VFD should on a high torque asynchronous motor like a windlass.
 
Curious, but you want to vary the speed of the windlass?

I have an AC powered windlass.
I dont know who made it.
It has a simple full wave rectifier inside converts the AC to DC and uses a Briggs & Stratton electric 48 vdc motor. I had to repair a loose broken brush in the motor.

This AC windlass is great, very powerful, and simply plugs into an outlet.
Motor is small, windlass pulls a foot per second.

Picture links
https://goo.gl/photos/VpAb8keEafHahqKS7
 
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Does anyone have experience using a variable frequency drive on an 110/220v anchor windlass? It appears that a soft starter wouldn't work, but a VFD should on a high torque asynchronous motor like a windlass.

I'm pretty sure that a VFD only works in conjunction with a 3-phase motor, so you would have to change the motor to a 3-phase model, and the VFD would be a more complicated model that creates 3-phase from a single phase input. It's essentially a 3-phase inverter. I suspect it could be made to work, but would probably be quite expensive to put together.

I assume you are looking for speed control? Or maybe just a controlled ramp up to normal speed rather than a jolt on/off? There are times when I'd like that too.....
 
Keep it simple. A DC motor on batteries will work even if gennie does not. I would not want complex digital inverter drives on a mission critical piece of equipment. Half the boats out there have rot around windlass motor and solenoids, not a great place for digital electronics. With the steep gear reduction starting torque should not be an issue. Really a good application for a DC motor's torque curve.
 
Well the shipyard that I am having discussions with has spec'd as standard equipment a 230v 50Hz commercial windlass. Actually all pumps, motors, lights, etc. in the entire vessel are spec'd at 230v.

So I am considering his proposal to be an all electric boat. However I can only afford a single genset, so I need to consider a large inverter to be the second "generator."

So the purpose of the VFD is not necessarily to vary the speed but more to provide a reduced startup amperage that would be within the specs of the inverter.
 
Well the shipyard that I am having discussions with has spec'd as standard equipment a 230v 50Hz commercial windlass. Actually all pumps, motors, lights, etc. in the entire vessel are spec'd at 230v.

So I am considering his proposal to be an all electric boat. However I can only afford a single genset, so I need to consider a large inverter to be the second "generator."

So the purpose of the VFD is not necessarily to vary the speed but more to provide a reduced startup amperage that would be within the specs of the inverter.

Soft starter and frequency inverter
So you need a soft starter, not a vfd.

It is the start up of a motor from 0 rpm that creates this intense current demand.
If you got the motor to turn using a smaller motor first I think it would take the load easily. But no one does that, but the idea is like when they start a huge diesel using a kicker fossil fueled motor. So then they do this electronically using a soft starter.

Can you get an inverter that has a built in soft start capability?
 
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50 Hz is European, If they must do this spec 60Hz which is what you will find in North America. This means the Generator as well unless this vessel is going to the Mediterranean
 
My winch is 240v, 1P, and will run on a generator or inverter. No special controls. Original motor was DC, before my time. My boat is mostly AC, appliances, lights, boiler controls, pellet stove. DC is only a few lights, marine electronics and some electric bilge pumps.
 
VFD is usually used to drive three phase motors, which is a good way to go. Is that what is being proposed? Is boat set up for three phase on other equipment?
 
Does anyone have experience using a variable frequency drive on an 110/220v anchor windlass? It appears that a soft starter wouldn't work, but a VFD should on a high torque asynchronous motor like a windlass.


I just can't see a VFD in this application.... Soft Start yes ! however with the reduction that is usually in the windlass gearbox, I would think that this motor will come up to speed instantly ( as opposed to direct drive that would demand max. torque ) so the momentary bump in start up current should not be an issue. Reversing this motor would be more of an interesting issue ....... just sayn'
 
VFD makes sense to me. Size, cost and reliability of VFDs have made great advancements. A good NEMA enclosure with proper ventilation would be important though.

Soft start might not be a good idea if you need to start the windlass under load (think wind and waves) and there is no relative movement.

A VFD gives you speed control without the loss of torque.

If you are in a bad situation, and need to pull the hook, with a soft start, you may not be able to produce enough torque to pull the anchor. Also, once the motor brake comes off, you may actually go backwards, and could possibly trip.

I've seen this exact situation many times on (over)loaded conveyors. Typically speaking, cranes don't use soft start on the hoist for this reason.

With a VFD, initial speed setting is 0 which allows instantaneous torque with no relative movement.

Definitely use a VFD on your thrusters. That would be sweet.
 
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Maxwell technical support state the a soft start will not work. It must be a VFD, just as NorthernSpy mentioned.

Definitely use a VFD on your thrusters. That would be sweet.

Yes I contacted Vetus technical support and they stated to use a VFD would cut startup power draw demonstrably. I can't find the email just now, but I recall it was about half.
 
Yes I contacted Vetus technical support and they stated to use a VFD would cut startup power draw demonstrably. I can't find the email just now, but I recall it was about half.

I was thinking more if the proportional control aspect. Low speed, low thrust; high speed high thrust. Or a nice non-cavitating ramp up to speed.
 
I can't find the email just now, but I recall it was about half.

Sounds about right to me. Single phase VFD's are quite common now for those upthread questioning if they where just for 3 phase. Elegant and pretty bulletproof solution to a thorny problem.
 
If you are going with a VFD, then why not use a 3ph motor? Way better motors than 1ph. No provisions needed for start windings/caps/switches.

I will say I'm a little out of my comfort zone talking VFD's. All I know is I set up my 3ph lathe and mill using vfd vs original static inverter, and the vfd is the cat's meow. Never fooled with vfd and single phase.
 
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