Interface Simrad AP with Garmin Plotter

[sandspur1966]

I recently had installed a new suite of Garmin 5000 series electronics including the 5212 in the pilothouse and 5008 on the bridge along with the HD radar. I am adding a Garmin "smart" transducer for speed, depth and temp as well as an aft facing camera to the system. So far i like everything but had a question regarding interfacing the the Garmin network with my autopilot.

Has anyone done this? I know the old Robertson/Simrad units have Nav functionality that frankly I have never used even though I have had the same unit on three different boats.

This isnt a high priority for me but I thought maybe someone else has done the legwork and can advise whether it is worth doing. I can see some convenience in that, as the Garmin runs through a route, it could direct the AP to make course corrections.

[Boatsb]

A lot depends on the autopilot.

What is it?

[Pascal]

Most AP accept data from yr electronics but honestly I have never used that feature even on long offshore legs. I prefer setting the heading manually based on Plotter/chart data

[sandspur1966]

Hi Scott, it is a J300 junction box and I believe the control heads are AP20's

Pascal, I am with you... I imagine, even with the functions working I will likely set course changes manually but since I am in "electronics mode" I figure it cant hurt to have it set up if possible.

[REBrueckner]

It's a nice function to use, but not critical...and depends on the type courses you typically run. For Fla to the Bahamas for example, it's nice to have but not critical I would think.

When I installed my SIMRAD autopilot in 1999, myself, it also used the J300X junction box and I happened to use the AP22 (smaller) control head since it fit my helm location better. I'm pretty sure at that time all the "smarts" were in the J300X to fit any control head.

I had several different brands of chartplotter/GPS interfaced....from different satellites for redundancy and all via NEMA 0183 protcol. When coming to the end of a leg I got a query which I don't remember exactly but something like "Next leg?" So you had to tap a button to change course for a new leg....otherwise you remained on the prior course.

The big advantage I found to the "NAV" function on the autopilot was when in that mode the the GPS allowed the autopilot to steer based on cross track error and course: So no matter how long I ran and no matter how strong the awthartship currents, I'd be within, say, 50 feet of the course I set.

A disadvantage is that if you fool around after a course change is required and are slow in following the new track, say because another vessel is blocking your way,or a buoy has been moved and then allow the GPS to correct your course it may turn your boat, say, 45 degrees if you are,say, 200 feet of the course leg track....So in those circumstances what I used to do is (with the autopilot off "NAV") manually set the auotpilot a degree or two towards the direction I needed to go to reduce cross track error....so I'd return to the original track.
more gradually. Another minor disadvantage is that every so often the boat would turn a bit...appear off course several degrees...as awthwartship currents were encountered. That sure caught my attention in strong currents around southern Nova Scotia.

If you manually look at your chart plotter display you can make such corrections to cross track error deviations manually.

I very much liked the "NAV" function because single handing my Hatt 48YF meant I was away from the helm station periodically and when I returned I was alrways dead on the course I set.

[doc g]

I have mine set up that way . It is nice to have and corrects for cross currents /wind etc. I think I recall that there is a data box ?? that you need to add then the gps connects using NEMA output. I'm not sure cause I was adding a PC /chartplotter at the same time. Simrad has great support (usually)by phone they can help you set it up. Call tech support........Pat

[Bugsy]

Captain Ned from this forum did the interface wiring for me (using NMEA) from my Simrad AP 20 with Junction Box 300X (?) to my Garmin 2010C chartplotter.

VERY easy connections (three butt connects) and as stated, I prefer using Nav mode to manually setting and revising a course because of auto corrections for wind and current through Nav. I just use multiple waypoints and go from one to the next---never leaving the helm unattended, of course.

[Boatsb]

I believe that is all NMEA 0183 so there are limitations on what can be interfaced and how many other items can be on the system.

[Norm Mayer]

I interfaced a Simrad AP with Garmin 4210 Chartplotter, and it works well. The only problem with the installation is even tho they both talk on the new "2000" protocol, I had to buy an adapter box to hook up the two comunication cables.

[REBrueckner]

Posts 6,9: anybody know what function such "data" or "adaptor" boxes performs. I did not use any for my installation described above and don't know when they might be required.