The Therm-O-Disc type 12S series time delay relays and sequencers are field-proven devices for controlling the operation of heating elements and/or fans in electric furnaces and heat pumps. These controls combine a solid-state positive temperature coefficient (PTC) heater with bimetal actuated contacts to provide time-delayed electrical switching. A wide variety of bimetal disc and PTC combinations are available to provide a broad range of timings.
- Available with auto-reset SPST, DPST and SPDT switch configurations.
- PTC heater for stable operation over a wide range of temperatures and voltages.
- Snap-action bimetal disc for high-speed contact separation.
- Standard operating ambients between -40°F (-40°C) and 150°F (65.6°C).
- Available with a wide variety of terminals and mounting plates.
- Welded construction for integrity of current-carrying components