Wiring an Autohelm ST 800

[FergusM]

I have an old ST 800 with no plug. I want to fit it to my Hunter Horizon 21, which has certainly had one at some time, as there is a lined socket in the cockpit seat for the pin at the outboard end of the unit, and two holes in the tiller that I reckon must have held the bent bracket with the pin that fits to the end of the ram. I am no electrical expert, to say the least, but even I can see that it has three wires. I think I should be able to buy a waterproof 3-pin plug and socket (I see that Force 4 sell them), and run the positive and negative connections to a spare Aux switch on the fuse/switch panel in the cabin. I take it that the 3rd wire is an earth, but I am not sure what happens to it. Any suggestions welcome.

 

[VicS]

I have an old ST 800 with no plug. I want to fit it to my Hunter Horizon 21, which has certainly had one at some time, as there is a lined socket in the cockpit seat for the pin at the outboard end of the unit, and two holes in the tiller that I reckon must have held the bent bracket with the pin that fits to the end of the ram. I am no electrical expert, to say the least, but even I can see that it has three wires. I think I should be able to buy a waterproof 3-pin plug and socket (I see that Force 4 sell them), and run the positive and negative connections to a spare Aux switch on the fuse/switch panel in the cabin. I take it that the 3rd wire is an earth, but I am not sure what happens to it. Any suggestions welcome.

ST 800 ??

Mine ( one of the original analog Autohelm 1000 models) is wired using a " Driplug"
I suggest you investigate using similar http://driplug.com/ although it originally had a special plug and socket for "Seatalk" data connection.

Instruction manuals on the Raymarine website http://www.raymarine.co.uk/view/?id=5362


You may have to look at ST 1000 manual. I cant see one for ST800

 

[earlybird]

If it's an ST, are you sure it isn't an ST1000? AFAIK, there isn't an ST800, the 800 has only two wires, +ve and -ve.
If it's the former, is the 3rd. wire yellow? If so it's for seatalk, and can be ignored, unless you want to connect it to instruments, which doesn't gain you a lot.
Hope that helps.

 

[FergusM]

Many thanks for the responses. I think I was a bit confused, as I am back home now, and the unit is still aboard. I have two Autohelms. One has push-button controls, and one (I think an AH 800, after following VicS's link to Raymarine), has a rotating compass dial. I am not sure whether the push button model has a digital read out screen or not, as my memory is not as good as it used to be. It was my intention to fit the push button model. I have no wish, or, frankly, sufficient knowledge, to connect the tiller pilot to anything else. I just want the boat to steer herself on a course I have set. As earlybird says, I don't see much gain in getting other instruments involved.

As no one has said otherwise, I take it that the connection from the Driplug (thanks, VicS) to the distribution panel that I had in mind should work OK.

 

[VicS]

As no one has said otherwise, I take it that the connection from the Driplug (thanks, VicS) to the distribution panel that I had in mind should work OK.

It should but be sure the wiring is heavy enough to avoid excessive volts drop. I guess the manuals suggest what size of cable to use. If not one of us can guide you.

Mine is wired back to a switch and fuse on the distribution panel.

 

[FergusM]

Thanks, Vic. I ordered some stuff from Merlin Equipment, and they sent me some tinned wire that they assured me was more than adequate for the loads generated by a tiller pilot. I cannot remember the exact size, but it was heavier than the wire they mentioned for nav lights.

 

[alahol2]

I think I should be able to buy a waterproof 3-pin plug and socket (I see that Force 4 sell them), and run the positive and negative connections to a spare Aux switch on the fuse/switch panel in the cabin. I take it that the 3rd wire is an earth, but I am not sure what happens to it. Any suggestions welcome.

I have a TP10 tillerpilot, I also have an AH800 that I keep, and have used, as a spare. Both run off a 2 pin driplug with the same polarity. You can buy an extra driplug plug so both pilots have the same plug. If I remember correctly I have two mounting sockets (for the swivel pin), the two pilots are different lengths.

 

[FergusM]

Thanks, alahol2, that sounds sensible. I will do the same.