KSD9700/BK05-BB1D Metallic Shell Temperature Control Switch (90°C NO, 5A 250V)

The KSD9700/BK05-BB1D is a fixed-setpoint thermal protection switch. It uses a bimetallic disc that deforms with heat. When the surrounding temperature reaches its calibrated 90°C trip point, the disc snaps, mechanically opening its normally closed contacts to interrupt the circuit and protect the connected equipment from overheating.

Yes, provided the fan's current draw does not exceed the switch's 5A rating. This switch is rated for 250V AC/DC, making it suitable for direct series connection in 120V AC circuits. It will cut power to the fan when the local temperature at the switch reaches 90°C, acting as an automatic safety cut-off.

No, the 90°C setpoint is fixed and non-adjustable. This is a factory-calibrated, automatic reset thermostat. Once it trips and opens the circuit, the contacts will automatically close again when the temperature cools down below the setpoint, typically by 10-20°C, restoring power to the load.

For accurate sensing, the metallic body of the switch must be in good thermal contact with the component or area you wish to monitor. Mount it using thermal adhesive, a clip, or a screw. Connect the two pre-attached 7cm lead wires in series with the load (e.g., the hot wire) you want to control, ensuring all connections are secure and insulated.