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AlpHa Measurement Solutions
10540 Rockley Road
Houston, TX 77099

(Toll Free) 800-522-7920
(voice) 832-456-4100

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C621 & C621H Stainless Steel Conductivity Probes TEXT SIZE: A A A    PRINT THIS PAGE   EMAIL THIS PAGE

Standard Features

  • In-Line Installation
  • Temperature Compensation
  • Treated 316 Stainless Steel Body
  • Cell Constant Validated At The Factory
  • C621: IP 65 Detachable Plastic Cable Connector
  • C621H: NEMA 4 Aluminum Threaded Terminal Box
  • Temperature Sensors: 10K NTC, PT100 and PT1000


  • Temprature Range C621: 0 to 140°C
  • Temprature Range C621H: 0 to 205°C
  • Maximum Pressure C621: 150 psig at 135°C
  • Maximum Pressure C621H: 250 psig at 205°C
  • Wetted Materials: 316 Stainless Steel and PEEK
  • O-Rings: Viton1
  • Cell Constants: K=1.0, K=0.1 and K=0.01
  • Process Fitting: 1/2 and 3/4 Inch in either NPT or BSP Male Fittings

To ensure compatibility with your test sample, please choose a cell constant and temperature element prior to ordering.

Cell Constant of K=1.0 Drinking water, service water, beer, milk and juice.
Conductivity Ranges: 10 to 2000 µS/cm at 25°C.
Cell Constant of K=0.1 High purity water such as condensate and boiler feed water in power plants.
Conductivity Ranges: 0.5 to 200 µS/cm at 25°C.
Cell Constant of K=0.01 Specific resistivity or conductivity for monitoring ion
exchangers, reverse osmosis systems, ultrapure water
for the medical and electronics industry.
Conductivity Ranges: 0.055 to 20 µS/cm at 25°C.


1 A registered trademark of E.I. du Pont Nemours and Company