Interested in using one of our AIS Receivers with a Chart Plotter? This pages provides an overview of how to do it.

Smart Radio AIS Receivers can be used with chart plotters that support NMEA connections to AIS receivers. AIS support is a fairly new feature with chart plotters so this will only work if you have a chart plotter that is typically less than 2-3 years old. However, most of the popular current chart plotter models now support AIS. This includes:

• Raymarine C Series and E Series
• Garmin 3000, 4000 and 5000 models
• Standard Horizon CP chart plotters

As well, many other models from other vendors also work with AIS. Check with your chart plotter vendor to ensure that AIS is supported.

What is required to connect a Smart Radio AIS Receiver to my chart plotter?

An overview of the necessary connections between the AIS Receiver and both a chart plotter and a computer can be found by clicking on this diagram.

On the AIS Receiver end, you need:

• a Smart Radio AIS Receiver,
• a dedicated connection to a new or existing VHF antenna with our "SO239 to BNC Connector" or install our VHF Antenna Splitter to use your existing VHF antenna,
• a connection to 12 volt DC power for the AIS Receiver and the optional VHF Antenna Splitter,
• our "AIS Receiver Breakout Cable" using the "OUT" and "GND" leads or cut the serial cable included with the AIS Receiver and use the wires from pin 2 (normally brown) and pin 5 (normally yellow) or build your own equivalent cable.

On the chart plotter end, you will need:

• a cable supplied by the chart plotter manufacturer for connecting optional NMEA devices,
• your chart plotter installation manual (in order to determine which wires to connect to),
• a method for connecting the output wires from the AIS Receiver to the input wires on the chart plotter (e.g. a patch panel).

How do I connect the AIS Receiver to the chart plotter

Only two wires should be connected between the AIS Receiver and the chart plotter. Normally chart plotters have one or more NMEA device input / output ports for connecting NMEA peripherals such as AIS receivers. Chart plotters use a system for NMEA input ports based on one of the following two standards:

• Some chart plotters use a single signal wire for each inbound NMEA port and share a common ground for all NMEA input and output ports. In this case the AIS Receiver output signal wire from pin 2 is connected to an available chart plotter input signal wire and the ground wire from pin 5 is connected to the common ground wire. For example, Garmin 3000 models and the Standard Horizon CP180 use this system.
• The other method used by some chart plotters uses a pair of wires for each NMEA input port with one wire being a positive signal wire and other other wire being a negative signal wire. In this case the AIS Receiver output signal wire from pin 2 is connected to an available chart plotter input positive signal wire and the ground wire from pin 5 is connected to the input negative signal wire for the same port. For example, Garmin 4000 and 5000 chart plotters and Raymarine C and E Series models use this system. In some cases the above solution may not work and the wire from pin 5 may have to be connected to both the negative NMEA signal wire and the common ground wire on the chart plotter. See your chart plotter documentation for more information on whether this is required or not.

Consult the installation documentation for your chart plotter and AIS Receiver before attempting to connect your AIS Receiver to a chart plotter. Incorrect installation can result in damage to both your AIS Receiver and the chart plotter.

NOTE: The input wire for the AIS Receiver that is connected to pin 3 must not be connected to any wire on the chart plotter. As well, the output wires from the NMEA ports on the chart plotter must not be connected to the AIS Receiver.

Once the wires have been connected correctly and power has been turned on to both devices, you will need to set the baud rate on the chart plotter to the correct speed. By default, most chart plotters use 4800 baud for each port however the baud rate for the AIS Receiver is set to 38400 baud by default. To resolve this, you need to ensure that the chart plotter baud rate for the port you are using is set to 38400 baud or "high speed". See your chart plotter documentation for instructions on how to do this. As an alternative, you can change the baud rate on the AIS Receiver to 4800 baud. See our product documentation for details on how to do this. Finally, you may need to turn on or configure the display of AIS targets using your chart plotter set up menus. Again, see your chart plotter documentation for instructions on how to do this.

Garmin 4000 and 5000 model notes

The Garmin 4000 and 5000 series models use a paired signal wire system for the input ports for connecting NMEA devices. However, we have noted some issues that customers have experienced connecting an AIS Receiver to these chart plotters. Using the correct steps above for a paired port installation, no AIS targets are seen. This problem is due to the signal voltages used the Garmin device. In order to overcome this known problem, you should install a 420 ohm resistor across the two input wires where the AIS Receiver output is connected to the chart plotter port input. This will drop the voltage to a range that the Garmin device can work with.

A wiring diagram for connecting a Smart Radio AIS Receiver to a Garmin 4000 or 5000 series chart plotter can be viewed by clicking on this diagram.

NOTE: The resistor fix is not required for Garmin 3000 series chart plotters. These devices use the single wire with a common ground system for input ports and no resistor is required.

Raymarine C and E Series notes

The Raymarine C and E Series products also use a paired wire system for connecting an input NMEA device, so the above instructions for connecting to systems using paired signal wires will work fine. The following diagram from Raymarine's installation documentation shows the pin-outs for the NMEA Input Cable.

The output wire from pin 2 of the AIS Receiver should be connected to the white NMEA Input (+ve) wire and the ground wire from pin 5 of the AIS Receiver should be connected to the green NMEA Input (-ve) common wire on the Raymarine NMEA Input cable.

However, some customers have noted that even if the systems are wired correctly, the Raymarine chart plotter will not show the AIS system as being active. This is due to the way the Raymarine system recognizes an AIS receiver. In order for it to "see" the receiver, valid AIS data must be coming into the input port on the chart plotter at the correct baud rate. So if the baud rate is not set to the same value for both devices or if there are no AIS targets nearby, then the Raymarine device will show the AIS symbol with a "X" through it - meaning that AIS is not active. To resolve this, ensure that the baud rate is set correctly and you are in an area that has AIS targets.

These are the basic steps. Once you have your Smart Radio AIS Receiver connected to your chart plotter, you should see icons for both your own position and for AIS transponder-equipped vessels that are near you. In addition, most chart plotters include the ability to "zoom" into the target to view the full information about the vessel such as the vessel name, call sign, destination etc.

For more information on this subject, see our FAQ page, the online AIS Troubleshooter and the product documentation that comes with the AIS Receiver and your chart plotter. If you have additional questions, send email to: info@milltechmarine.com.