Calibrating a Water Speed Sensor Using a Chartplotter

 A water speed sensor or a water speed-sensing transducer connected to a chartplotter makes it possible to calibrate that speed-sensing device to improve the accuracy of water-speed data displayed by the chartplotter.

The transducer's water speed-sensing (paddlewheel or Ultrasonic type) measures water flow, and the transducer must be in the water to work correctly. The transducer does not provide water flow data when it is out of the water.  

Calibration of sensors

For  sensors connected to a chartplotter or a sonar module, select Options > Settings > My Vessel > Calibrate Water Speed.

For NMEA 2000 Sensors, from the chartplotter, select Options > Settings > Communications > NMEA 2000 Setup > Device List > Transducer to be calibrated > Review > Calibrate Water Speed.

1. Follow the on-screen instructions

2. Bring the boat up to the desired cruising speed and then maintain a constant speed

3. If the vessel is not moving fast enough or the speed sensor is not registering a speed, a message appears; take appropriate troubleshooting steps (see below: Troubleshooting)

4. Take note of the rate of speed. It is not necessary to stop the boat

5. Select Finish Calibration - Enter the rate of speed noted while maintaining a constant cruising speed or use the speed provided in the keypad

6. Select Done

Troubleshooting

If calibration fails or is incomplete, a message appears. Press OK to clear and attempt calibration again. 

1. Increase or decrease speed

2. Check the paddlewheel on the speed sensor. It should move freely

3. Disconnect the connector and inspect the connection; if connected via NMEA 2000, verify NMEA 2000 backbone is a reading sensor

4. If the message continues, contact Garmin Product Support

NOTES:

• DST 800 and DST 810 may show on the NMEA device List as a DST 200 

• Use either the chartplotter or Airmar CAST app to calibrate the DST 810

• GST 43 will show up as GST 10