The SDB500 is a Direct Mounting Temperature Swichgage instrument used to monitor gas compressor temperatures or engine exhaust temperatures. It is an accurate direct-reading gauge with an adjustable limit switch to activate alarms and/or shutdown. A knob on the front of the instrument allows you to adjust the limit switch trip point. Pointer movement is actuated by a bi-metallic sensing element. Temperature Switch
When the indicating pointer on the SDB500 touches the adjustable contact, a one-wire-to-ground circuit is completed to shut down the equipment and/or actuate audible or visible alarms. Proper relays or Tattletale annunciators (magnetic switches) must be incorporated into the system.