NMEA 0183 to 2000 Conversion & Axiom

[Chuck - Raymarine - Moderator]

Welcome to the Raymarine Forum Jon,

Q1: My existing system consists of three E-120 classic MFDs and has both a NMEA 0183 bus and a NMEA 2000 bus.
Display #1 (Master) connections are: 1) NMEA 0183 connection-input (muxed signals from GPS, Heading Sensor, and Auto Pilot) and output to NMEA 0183 bus "listeners" (ACR locator beacon (GPS and Time); iCom VHF radio (GPS and time)) ; 2) Pathfinder Radar connection; 3) Seatalk2 connection from NMEA 2000 bus (Trim Tab Sensors and Weather Station); 4) Seatalk HS connection to Seatalk HS Network Switch (SR-100; DSM-300; E-120 MFDs x2 repeater units); 5) Video Camera inputs and 6) VGA output to a VGA monitor in the main salon.
Display #2 (Repeater) connections are: 1) NMEA 0183 AIS input from Raymarine AIS-650; 2) Seatalk HS connection to Seatalk HS Network Switch.
Display #3 (Repeater) connections are: 1) Seatalk HS connection to Seatalk HS Network Switch.
A1: It is not quite clear what your intentions are for the NGW-1. E-Series Classic MFDs are not designed and tested for use in systems having more than one source of any specific type of data (NMEA 2000 engine, trim tabs, and tank level sensors excluded). After reviewing the equipment which you have listed, I have a concern that the MFD may be receiving heading data from two sources (i.e. "Heading Sensor, and Auto Pilot"). As many Airmar Weather Stations transmit GPS data and heading data, I also have a concern that the "Weather Station" may act as an additional source of GPS and/or heading data within the system. Should duplicate sources be present of any specific type of data be present within the system, then action must be taken (ex. disconnecting the the associated additional source(s), programming the device to not transmit data items available from another source in the system, or programming the MUX (if possible) to not pass data item available from another source).

Q2: Are there any issues with added the NGW-1 to the NMEA 0183 muxed signals (Display #1; Connection #1)?
A2: It is not clear what your intentions are for the NGW-1. Please elaborate.


Q3. Assuming there are no issues, could I then reconfigure the NMEA 0183 input on display #1 to receive the AIS-650 and continue to use the output wire pair for the "listeners" on the NMEA 0183 bus?
A3. Should input from an AIS receiver/transceiver be fed to the NMEA 0183 MUX, then that MUX would in turn need to be configured to transmit at 38400 BAUD and the MFD's NMEA 0183 port would need to be configured to operate a 38400 BAUD. As changing the BAUD rate of the MFD's NMEA 0183 port also affects its output port, making the change suggested would likely break communications between MFD #1 and the 4800 BAUD NMEA 0183 listeners (ACR locator beacon (GPS and Time); iCom VHF radio (GPS and time)). You may want to consider using an E70196 VHF NMEA 0183 to STng Converter Kit to supply the 4800 BAUD NMEA 0183 listeners with GPS data. Doing so

Q4. If this all works, at some future date I would add a stand-alone AXIOM 12 with 3D Realvision after the thru hull sender becomes available. I would then like to connect the AXIOM to the NMEA 2000 bus so it has all of the other E-120 "non-graphical" data. Will that work?
A4. Should the AIS650 would need to continue being interfaced via NMEA 0183 to the system of E-Series Classic MFDs to support having them display AIS information. The AIS650 would additionally need to be interfaced to the SeaTalkng backbone to support having the Axiom MFD display AIS data. As you have suggested, no graphical data would be shared between the Axiom MFD and the E-Series Classic MFDs.