Dwyer Sales Department: 1-201-419-6111 ext. 26 for Sales Group  |  dwyer@nciweb.com

Dwyer Series GS Gap Switch

Liquid Level Measurement, 1000:1 Wet/Dry Ratio, 316 SS Wetted Parts

Series GS Gap Switch measures liquid levels at a single point and provides a 10A relay output for high or low level alarm, overflow prevention, and pump protection. The Series GS uses ultrasonic wave propagation between the transducer gap to sense the presence or absence of a liquid. Integral electronics make installation quick and easy. Units can be mounted in either a vertical or horizontal position with no additional calibration required. Gap switch includes a 0.5 second delay and high level failsafe.

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  • REPEATABILITY: 2 mm (0.078") typical.
  • DELAY [ON]: 0.5 seconds.
  • WET/DRY RATIO: 1000:1.
  • SUPPLY VOLTAGE: 115 VAC, 50/60 Hz (230 VAC optional).
  • OUTPUT: 10A DPDT relay.
  • IMMERSION DEPTH: 1" (25.4 mm).
  • SENSOR MATERIAL: 316 stainless steel.
  • MAXIMUM PRESSURE: 1000 psig.
  • TEMPERATURE RANGE: Sensor: -40 to 200°F (-40 to 93°C),
  • Electronics: -20 to 170°F (-4 to 77°C).
  • HOUSING: Epoxy-coated cast aluminum, NEMA 4 & 7.
  • MOUNTING: 3/4" NPT(M).
  • WEIGHT: 1.0 lb (453 g).
MODELS NUMBERS (stock shown in bold)
Model Number Immersion Depth Cable Supply Voltage
GS10001 1" (25.4 mm) 115 VAC
GS20001 1" (25.4 mm) 230 VAC
Monitor and control levels of water, chemicals, lubricants, acids, creams, lotions, beverages or paints in vessels, storage bins, tanks, sumps, etc.