Hi all,

I thought I would post an article on my recent work to integrate a fairly newly installed Raymarine Axion chart plotter, i70s MFD and ITC-5 transducer module with an original Raymarine S3G Course Computer on my SM.

The original nav equipment was removed from the SM after the supposed strike to the boat but the original autopilot system has been working since that event. When I acquired the boat, the Axiom/i70s/ITC-5 system on the SeaTalkng bus was completely separate from the Autopilot system. They were not conversing at all. The ST7001 simply responded with NO DATA with every attempt to link plotter with autopilot.

With the aid of the Raymarine tech support team, I implemented a NMEA2000 <-> NMEA0183 converter technology into the system using initially, the Raymarine E22158 SeaTalk to SeaTalkng converter and then later with the ActiSense NGW-1-STNG converter. This offering is different from the E22158 which apparently comes with some deficiencies that the NGW-1 does not have. Specifically, the E22158 does not pass Magnetic Variation data. The ActiSense also connects to the S3G course computer via one of the two NMEA ports vs the SeaTalk ports where the E22158 would connect. Other than the manual from the ActiSense vendor showing a backwards wiring configuration (NMEA inputs and outputs are reversed), the converter works wonderfully and we now have full communications between the systems with XTE, DTW and BTW data being presented to the ST7001 autopilot head for course updates to waypoints. 

I've added a diagram of the system as I currently have it and have, since the addition of the ActiSense converter, added a couple i50's, an i60 and a second i70s. I can now see just about any data source I want on the two i70s including AIS, engine and genset data without cluttering the chart plotter screens and can also have this data displayed anywhere on the boat using Raymarine apps that link an iPad to the MFD's.

The primary driver for my writing this was that it took me several tries to get the ActiSense unit to function on the NMEA bus because the manual showed the wires reversed from that which actually works - if it weren't for the advise of a Raymarine tech to reverse the wires, I would still be scratching my head as to why this system was not working! Not all manuals are as they should be!!!

Tony
SM#443-GRAND CRU

[Edited Message Follows]

Bill, I installed none of those per se. The model number was the NGW-1-STNG which is identical to the ISO (running at 4800 baud as does the S3G) except it comes with a white Raymarine spur cable that connects to the NMEA2000 side of the unit so you can plug it directly into the Raymarine SeaTalkng backbone (white connector on any of the backbone to spur accessories (A06064, E70196, E22158 (not shown)) in the diagram I attached).

Denis, the only source of XTE, DTW and BTW that I know of comes from the chart plotter after you have programed your course into it. It sends the distance to waypoint and bearing to waypoint to the SeaTalkng bus based on the waypoints you program and the course you intend to track. If the connection fails (for whatever reason), the autopilot will simply revert back to not communicating with the chart plotter and show "NO DATA" for XTE, DTW and BTW when you attempt to use the TRACK mode on the autopilot head (ST7001). In that case you simply use the AUTO mode and auto-steer using this mode of the autopilot system until you can affect repair. I already had that mode of operation available to me but I wanted to get the chart plotter waypoint data to the course computer to fully utilize the capabilities of the SG3 and ST7001 for "hands free" navigation. If the communication path fails, I can go back to what I had before where I manually control the bearing for the autopilot in the AUTO mode, or steer manually in STANDBY mode. 

Alternatively, I also have the E22158 on board which connects to a SeaTalk port of the SG3. I've already tested this configuration as well and although certain data is missing in the implementation of the E22158 NMEA2000 to NMEA0183 converter, it too effectively sends XTE, DTW and BTW data to the S3G from the SeaTalkng bus for full autopilot/chart plotter integration. You simply have to be aware that magnetic variation is not a data item sent to the S3G and so you need to manually enter that into the ST7001 as your course progresses. Quite that pain in the butt I'm told however, for me, I now have two sources of data conversion from the SeaTalkng devices (Axiom MFD); the ActiSense and the Raymarine E22158. I have redundancy, although I have been advised by Raymarine that it is probably not a good idea to have both converters (NGW-1-STNG and E22158) on the network at the same time so I keep it as a spare. It's less than half the price of the ActiSense converter and a good backup.

Hope that helps.

BTW, there are three versions of SeaTalk: SeaTalk1, SeaTalk2 and SeaTalkng (next generation). The S3G and ST7001 are SeaTalk1, the rest of the stuff on the network is SeaTalkng.

Tony 
SM#443-GRAND CRU