ST 50+ Tridata

[Steve - Raymarine - Moderator]

I have enclosed a speed transducer test. This will determine if there is an issue with the transducer. Is the transducer cleaned through out the year? Is the paddlewheel covered in debris when cleaned?

Testing the Speed Sensor:

Verify that the transducer’s paddle wheel is free of marine growth and rotates freely on its shaft
Power down the instrument
Disconnect the GREEN and SHIELD transducer leads from the instrument display or instrument pod.
Connect a multimeter to the GREEN and SHIELD transducer leads and configure the multimeter to measure continuity or resistance.
Slowly rotate the transducer paddle wheel by hand. Note that as the paddlewheel is rotated, the multimeter should alternate between an open circuit and a closed circuit with each quarter turn. As such one complete revolution of the paddle wheel should open and close the circuit four times.

Should the multimeter respond as indicated above, then the speed sensor element of the transducer would be deemed functional. If not, then the transducer has failed and should be replaced.