The Murphy SDB500-3 is a Direct Mounting Temperature Swichgage device that provides an accurate direct-reading gauge with an adjustable limit switch to activate alarms and/or shutdown. A knob on the front of the Swichgage allows you to adjust the limit switch trip point. Pointer movement is actuated by a bi-metallic sensing element. When the indicating pointer on the SDB500-3 touches the adjustable contact, a one-wire-to-ground circuit is completed to shut down the equipment and/or actuate audible or visual alarms. Proper relays or Tattletale annunciators (magnetic switches) must be incorporated into the system.
A thermowell (separable socket) is used to facilitate maintenance of a temperature Swichgage and to protect the temperature sensing bulb from extreme amounts of system pressure.
Applications: The most common use of the SDB Series is to monitor gas compressor temperatures. Engine exhaust temperature can also be monitored to indicate over-loading or lean fuel mixtures; or use the SDB to help coordinate loads on twin-engine installations.
- Easy to Read Dial
- Bi-Metallic Sensor
- 100 to 500°F (40 to 260°C)
- Dials Scaled in Degrees Fahrenheit/Celsius
- Sand-Cast Aluminum
- 3/4 NPT Thermowell
- Part No.: SDB500-3
- Temperature Ranges: 100 to 500°F (40 to 260°C)
- Sensing Bulb Material and Size: 304 stainless steel; 1/2 in. dia. x 4 in. (13 x 102 mm) insertion depth
- Maximum Bulb Pressure: 285 psi (1.97 MPa)[19.7 bar] at 625°F (329°C) NOTE: use of a thermowell is recommended
- Process Connection: 1/2 NPTF
- Sensing Element: High torque bi-metal element in heliarc welded stainless steel bulb
- Contact Rating: 2 A @ 30 VAC
- Limit Contact Adjustment: By knob through full range
- Maximum Unit Temperature: 625°F(329°C)
- Case Material: Sand-cast aluminum
- Swichgage Accuracy: ± 3% of full scale
- Wire: 18 AWG (1.0 mm2). See Dimensions for lengths (image #3), reverse side
- Dial: Black print on stainless steel. Dials are scaled in degrees Fahrenheit and Celsius
- Shipping Weight: 2 lb. (1.0 kg)
- Shipping Dimensions: 8-1/4 x 4-1/4 x 4-1/2 in. (210 x 108 x 114 mm)
NOTE: All models are calibrated for use with a thermowell.