SDB Series

Direct Mount Temperature Gauges with Adjustable Limit Switch

The SDB Series gauges are commonly used to monitor gas compressor temperatures. Engine exhaust temperature can also be monitored to indicate overloading or lean fuel mixtures.

  • East-to-read dial
  • Bi-metallic sensor
  • Two temperature ranges
  • Dials scaled in degrees Fahrenheit and Celsius
  • CSA listed explosion-proof model available

FW Murphy Production Controls offers support for all our products. If you are unable to find the product that you need, please call us at 918-957-1000.

  • Overview
  • Specifications
  • Diagrams
  • Literature

The SDB Series is a direct-mounting temperature device. It provides 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.

The most common use of the SDB Series is to monitor gas compressor temperatures. Engine exhaust temperature can also be monitored to indicate overloading or lean fuel mixtures, or use the SDB to help coordinate loads on twin-engine installations.

  • Temperature Ranges:
    • SDB500, SDB500EX and SDB501: 100° to 500° F (40° to 260° C)
    • SDB1000: 200° to 1000° F (100° to 500° C)
  • Sensing Bulb Material and Size: 304 stainless steel; 1/2 in. dia. x 4 in. insertion depth (13 x 102 mm)
  • 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; 3/4 NPT adapter available
  • Sensing Element: High torque bi-metal element in heliarc welded stainless steel bulb
  • Contact Rating:
    • SDB500, SDB501 and SDB1000: 2 A @ 30 VAC
    • SDB500EX: 2 A @ 120 VAC
  • Limit Contact Adjustment: By knob through full range
  • Maximum Unit Temperature:
    • SDB500, SDB500EX, SDB501: 625° F (329°C)
    • SDB1000: 1250° F (677° C)
  • Case Material:
    • SDB501: Die-cast aluminum
    • SDB500, SDB1000, SDB500EX: Sand-cast aluminum
  • Accuracy: ± 3% of full scale; NOTE: All models are calibrated for use with a thermowell; Specify when a thermowell is NOT to be used when ordering
  • Wire: 18 AWG (1.0 mm2); See Dimensions for lengths
  • Dial: Black print on stainless steel; Dials are scaled in degrees Fahrenheit and Celsius
  • Approximate Shipping Weight:
    • SDB501: 1 lb. 4 oz. (0.57 kg)
    • SDB500 and SDB1000: 2 lb. (1.0 kg)
    • SDB500EX: 2 lb. 5 oz. (1.05 kg)
  • Approximate Shipping Dimensions:
    • SDB501: 8-1/4 x 4-1/4 x 4-1/2 in. (210 x 108 x 114 mm)
    • SDB500 and SDB1000: 8-1/4 x 4-1/4 x 4-1/2 in. (210 x 108 x114 mm)
    • SDB500EX: 9 x 5-1/2 x 6 in. (229 x 140 x 152 mm)

Dimensions SDB500, SDB500EX and SDB1000

 

Dimensions SDB501

 

Wiring SDB500, SDB501, and SDB1000

 

Wiring SDB500EX

 

For more information about this product, you can download the related literature here:

Sales Bulletin (7543; revision date – 04/2019)

Installation Instructions (00-02-0043; revision date – 05/2020)