Connecting the Temperature Sensor of a Transducer to a GSD™ 26 While Leaving the Depth Disconnected

The thermistor (temperature sensor of a transducer) can be connected to the GSD™ 26 professional sonar module without the depth portion being connected. The thermistor has to have a maximum of 10k ohms. To find out if the thermistor is less than or equal to 10k ohm, use a multi-meter to measure the amount of resistance between the Temp + (usually White) and Ground (usually Brown) wires of the transducer. Please verify that the wire colors are correct by contacting the manufacturer of the transducer.

There are certain times when a separate Non-Chirp transducer's thermistor needs to be used to read the water temperature. One example is if the Chirp transducer that is being used does not have a thermistor (in-hull transducers). In this situation, the depth reading will come from the Chirp transducer and the temperature reading will come from the Non-Chirp transducer.

To connect the Non-Chirp transducer's thermistor to the GSD 26, follow these instructions:

1. Cut the connector off the end of the transducer's cable

2. Strip some of the insulation around the following wires

   • Temp + (positive)

   • Ground

     • If unsure of the wire colors for the above two wires, contact the manufacturer of the transducer

     • It is recommended to tin the stripped wires for easier installation

3. Connect the Temp + (positive) wire of the transducer to the Temp terminal of either the Low or High Frequency side of the GSD 26

4. Connect the Ground wire of the transducer to the GRND terminal in the same location as the Temp + wire was connected

5. Connect the Bare (Shield) wire of the transducer to the Shield terminal in the same location as the Temp +  and Ground wires were connected

Once the transducer is connected in the manner described above, a setting may need to be changed to tell the chartplotter which side of the GSD 26  that the temperature sensor is connected to. Follow these instructions to check this setting:

1. Select Sonar from the Home Screen

2. Press the Menu button

3. Select More

4. Select Advanced

5. Select Temp Source

6. Select one of the three options:

   1. High Frequency - Select this option if you connected the thermistor wires to the High Frequency channel of the GSD 26 

   2. Low Frequency - Select this option if you connected the thermistor wires to the Low Frequency channel of the GSD 26 

   3. Auto - Select this option will make the GSD 26 use the first valid temperature source it finds when looking at either the Low or High Frequency channels. This should be chosen by default

Once the thermistor has been connected and the GSD 26  configured to display the correct channel, the temperature data should be displaying on the Sonar screen.