St4000 autopilot connections

[jimmyk]

Hello. I have the above autopilot. I want to connect the gps plotter to it. Along with the wiindvane(wired to top of mast). At the rear of the autopilot there is a place to connect two wires for nmea. Can I connect both the wind instrument and the gps? Excuse my ignorance

 

[pvb]

Hello. I have the above autopilot. I want to connect the gps plotter to it. Along with the wiindvane(wired to top of mast). At the rear of the autopilot there is a place to connect two wires for nmea. Can I connect both the wind instrument and the gps? Excuse my ignorance

You can connect them both via a multiplexer. If you don't use a multiplexer, the NMEA messages will clash and won't work.

 

[jimmyk]

You can connect them both via a multiplexer. If you don't use a multiplexer, the NMEA messages will clash and won't work.

Are these expensive. They sound it��

 

[bedouin]

I've connected mine up with a 2 way switch that allows me to connect either the windvane or the GPS, but not at the same time. Otherwise as prv says you need a multiplexer.

In theory the GPS plotter could retransmit the wind data combined with its own output, but I don't know if any support that (I think in the past I have heard of people using TickTack instruments to do this)

 

[bryeomans]

I would go with the switch - you either want the autopilot to track a GPS route or follow the wind if conditions permit- it cannot do both at the same time anyway!. With a switch, you can always switch between them. Resetting the track function to follow a goto instruction from where you have arrived using the wind direction just requires a simple goto instruction to the GPS ( at least with my simple GPS12 Garmin) and changing to Track with the 4000.

Your other problem is compatibility, my ST4000 will track the Garmin but have not been able to rig it to follow Tactick wind data even using a Miniplex multiplexer to control data flows between the various inputs and my onboard PC. At least with a switch you can try it out and see if the 4000 will read the connection first - if it works it works but if not no problem and minimal expense.

 

[earlybird]

My Raymarine Seatalk system integrates wind instrument and Tillerpilot, it's part of the package, but if it wasn't, then I wouldn't spend money achieving it.
If the wind is free, relative to your course, or steady in direction, then sail direct to the GPS waypoint, trimming sails as required.
If close-hauled, and the wind is variable in direction, the system response is too slow to enable a good course. Sailing ~10deg. below optimum is necessary to avoid being taken aback if headed (and is recommended by Raymarine). You might then just as well sail a GPS course.
This very much limits it's utility.

 

[[3889]]

If close-hauled, and the wind is variable in direction, the system response is too slow to enable a good course.

That's not my experience with the ST 4000; I find it tracks shifts very well when close hauled. Better than I can

 

[bedouin]

My Raymarine Seatalk system integrates wind instrument and Tillerpilot, it's part of the package, but if it wasn't, then I wouldn't spend money achieving it.
If the wind is free, relative to your course, or steady in direction, then sail direct to the GPS waypoint, trimming sails as required.
If close-hauled, and the wind is variable in direction, the system response is too slow to enable a good course. Sailing ~10deg. below optimum is necessary to avoid being taken aback if headed (and is recommended by Raymarine). You might then just as well sail a GPS course.
This very much limits it's utility.

I have an idea that the ST 4000 always steers to its own compass but uses the wind/gps information at regular intervals to update the compass course to steer (every 30 or 60 secs I think) and in addition it must damp the wind reading too so I would think it could take some time to respond to a wind shift

 

[jimmyk]

Thanks for the replies. Does anyone know how I might wire a switch up. I was thinking the switch would go to the wind instrument but not much idea how I would wire it. Thanks