Generic KSD302 Ceramic Temperature Control Switch Thermostat - 135°C NC, 250V 10A

The KSD302 is a Normally Open (NO) thermal switch. This means its electrical contacts are open (circuit broken) at temperatures below its 135°C set point. When the surrounding temperature reaches 135°C, the internal bimetallic disc snaps, physically closing the contacts to complete the circuit. This action can be used to trigger an alarm, activate a cooling fan, or cut power to a heater.

Yes, the switch is rated for 250V AC/DC and can handle both types of current up to its 10A maximum. Ensure your application's voltage and current do not exceed these ratings. For inductive loads like motors or solenoids, derating the current or using a snubber circuit may be necessary to prolong contact life.

Mount the ceramic body securely to the surface whose temperature you need to monitor, using its mounting holes for good thermal contact. Wire the two terminals in series with the load (e.g., a heater coil or alarm circuit) you want to control. The switch will close the circuit when it detects 135°C at its mounting point. Ensure wiring is rated for the full load current.

The actuation temperature is fixed at 135°C and is not user-adjustable. It is factory-calibrated by the specific curvature and material of the internal bimetallic disc. For a different trip point, you would need to select a different model in the KSD series with the corresponding fixed temperature rating.