Another windlass relay question

[Storyline]

The Lewmar windlass we have has a switch mounted near the batteries that switches the power onto the relay/contactor. Is there any damage likely to be caused if we forget to turn it off (as we sometimes do) after using the windlass ? This is usually discovered a few hours later but it can sometimes be left on until the next time we anchor (usually the next day).

 

[Talulah]

Not an issue. The relay is sitting there passively even with the power turned on. As power is not being consumed by the relay there are no overheating issues.
(Not strictly true as often there is a light on the switch panel to show the windlass is turned on. So a very tiny consumption by the light.)
There are two safety issues:
1) someone may accidently operate the windlass.
2) An electrical short. These cables can carry large currents.
Both unlikely.

 

[prv]

The relay is sitting there passively even with the power turned on. As power is not being consumed by the relay there are no overheating issues.

It will be consuming a certain amount in the coil, surely? I've no real idea how much, but given the currents involved on the load side it must be quite a hefty relay with a commensurately large coil. My Smartbank battery system uses a similarly-sized contactor, and they consider it enough of an issue that the controller applies full power to pull in the contactor and then a reduced power (actually they're PWM-switching the full voltage) to hold it there.

Agree no risk of damage as such, but if it were mine I think I'd want to measure the draw of the coil to see how much power I was wasting by leaving it on.

Pete

 

[Talulah]

No. The coil will not be powered up.

 

[prv]

No. The coil will not be powered up.

Ah, I think I may have misunderstood. I think I combined "switch near the batteries" with the thread title, and read it as a relay near the batteries, controlled by a switch in a more convenient location and serving to turn the whole system on and off (ie separate from the box of up/down relays). Possibly because this is a system I'm planning to install on Ariam

With a chunky switch cutting the power directly (and on re-reading I think that's what it is) then I entirely agree with post #2.

Pete

 

[Storyline]

The switch is described as a circuit breaker and the type is shown on the bottom right of this image.

View attachment 44845

 

[prv]

The switch is described as a circuit breaker and the type is shown on the bottom right of this image.

Right - that's exactly the same one we have on Ariam. I regard it as a circuit-breaker in case of overload or short-circuit, not a switch for routine switching on and off. I leave it in the "on" position at all times.

This winter (if I get round to it) I will be adding a relay to the thin control wires (about where your diagram has the "Fuse 3A"), controlled by a switch in the cockpit. This will allow me to disable the buttons to prevent accidents, and also power down the receiver for the wireless remote I plan to add at the same time.

But that's additional complication because I like doing electrics. In your case, just leave the breaker on and don't worry about it.

Pete

 

[Storyline]

Thanks Pete, that will certainly reduce the amount of tetchiness onboard - 'you always forget to turn the windlass off' type of thing (actually a joke, we find that hardly a cross word gets spoken onboard, should really become liveaboards .....

 

[dial-a-monkey]

Sorry for the hijack - but does anyone know how or if the back emf is handled? - more specifically what happens to the large voltage spike when the contractor (relay) contacts are opened and the magnetic field collapses in the windlass? shouldn't there be a big voltage surge?

 

[GrahamM376]

This winter (if I get round to it) I will be adding a relay to the thin control wires (about where your diagram has the "Fuse 3A"), controlled by a switch in the cockpit. This will allow me to disable the buttons to prevent accidents, and also power down the receiver for the wireless remote I plan to add at the same time. Pete

I feed power to our wireless receiver from the windlass controller, which in turn is powered from the hefty windlass cables. When the circuit breaker is off, everything loses power so no battery drain or chance of accidents.

 

[prv]

I feed power to our wireless receiver from the windlass controller, which in turn is powered from the hefty windlass cables. When the circuit breaker is off, everything loses power so no battery drain or chance of accidents.

Yes, but I don't want to have to go down to the battery locker to flip the breaker every time I want to handle the anchor. So I have a "windlass" switch on my cockpit panel:

(This is a screenshot of the cutting file that went to the engravers, so black is white, white is black, and red lines are cutouts. Also the screenshot has come out a little distorted; the real thing is crisper.)

Pete

 

[GrahamM376]

Yes, but I don't want to have to go down to the battery locker to flip the breaker every time I want to handle the anchor. So I have a "windlass" switch on my cockpit panel:

I see your problem. I mounted our circuit breaker in the instrument panel, taking the feed from the battery isolator switch.

 

[prv]

I see your problem. I mounted our circuit breaker in the instrument panel, taking the feed from the battery isolator switch.

In my case that would involve a lengthy detour for the heavy cables, and I don't think there's even room in the ducting.

Pete

 

[john_morris_uk]

Yes, but I don't want to have to go down to the battery locker to flip the breaker every time I want to handle the anchor. So I have a "windlass" switch on my cockpit panel:

(This is a screenshot of the cutting file that went to the engravers, so black is white, white is black, and red lines are cutouts. Also the screenshot has come out a little distorted; the real thing is crisper.)

Pete

That's a neat panel. Forgive me drifting the thread momentarily, but I can see the logic of most of the combinations but Motor Low confuses me. (I assume Sail High means Tricolour and Sail Low means Port and Starboard Nav lights and stern light.). If Motor Low means Port and Starboard lights plus stern light, plus steaming light on the mast I can't see what Motor High would be? I assume high and low doesn't refer to power levels!

Edit: it occurs to me that Motor High could mean Port and Starboard lights with the All Round White at the masthead, whilst switching off the stern light...


Apologies again for thread drift...

 

[Talulah]

In my case that would involve a lengthy detour for the heavy cables, and I don't think there's even room in the ducting.

Pete

On a number of boats the heavy cables go direct from the battery to the relay with a circuit breaker somewhere on route. It's not normal practice to divert the heavy cables so the breaker can be located in the ideal position.
On a lot of boats the windlass breaker is where all the other master switches are and often that's in a rear cabin.
On some boats where the windlass battery is up forward the breaker will be up forward as well.
As has been pointed out it is not convenient to run up and down to turn the windlass breaker on/off etc.
Hence often a switch is installed. This provides power to the windlass controls whether they be foot switches near the windlass, an up/down rocker switch, or a wireless remote. This switch is often mounted on the main switch panel or in the cockpit and only needs to be a light weight switch. The switch usually gets its power from the downstream side of the windlass breaker but not always.

 

[prv]

it occurs to me that Motor High could mean Port and Starboard lights with the All Round White at the masthead, whilst switching off the stern light...

Exactly that

I don't think I've ever used it, but it's a legal combination for our boat so I thought I might as well have the option. There might be a situation where the light at the masthead is more visible.

I don't generally use the all-round white as an anchor light (I have one that hangs above the foredeck) so, since it was already there, I thought I might as well get some use out of it

Pete

 

[prv]

As has been pointed out it is not convenient to run up and down to turn the windlass breaker on/off etc.
Hence often a switch is installed. This provides power to the windlass controls whether they be foot switches near the windlass, an up/down rocker switch, or a wireless remote. This switch is often mounted on the main switch panel or in the cockpit and only needs to be a light weight switch. The switch usually gets its power from the downstream side of the windlass breaker but not always.

Errm, yes, this is exactly what I'm talking about installing, for exactly those reasons

Pete

 

[Storyline]

.....

This winter (if I get round to it) I will be adding a relay to the thin control wires (about where your diagram has the "Fuse 3A"), controlled by a switch in the cockpit. This will allow me to disable the buttons to prevent accidents, and also power down the receiver for the wireless remote I plan to add at the same time.
.....
Pete

Pete, if you have a moment would you post a link to the wireless remote you are planning to get please ? Have seen one mentioned on here but I have searched and cannot find it. From memory it was off Ebay and extraordinarily inexpensive.

 

[prv]

Pete, if you have a moment would you post a link to the wireless remote you are planning to get please ? Have seen one mentioned on here but I have searched and cannot find it. From memory it was off Ebay and extraordinarily inexpensive.

Don't have a link handy I'm afraid - I already have the remote in my "parts for upcoming projects" box.

There are dozens of them available on ebay though, can't be hard to find. What I will say is that you want the type with individual relays and screw terminals. The one that's pre-wired with "up" and "down" wires looks ideal, but it has a half-second delay in operation and that would make life very difficult when trying to snug the anchor into its stowage position without wrenching everything apart. The type I have is instant, like using a hard-wired button.

Pete