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Sensorex SD7420CD-ORP Differential ORP
Probe with Direct 4-20mA Output

Sensorex SD7420CD-ORP Differential ORP Probe with Direct 4-20mA Output

When an ORP sensor is constantly measuring a wastewater treatment process, it will be exposed to chemicals, suspended solids, and other contaminants. These contaminants can cause fouling of the ORP sensor reference, leading to sensor failure. Differential ORP sensors utilize three electrodes instead of the conventional two. This special design allows the sensor reference (salt bridge) and buffered electrolyte solution to be replaced, which extends working lifetime. Our SD7420CD features differential sensor technology with a direct 4-20mA output, so it can be integrated into control systems without the use of a transmitter or controller.

  • Reliable measurement performance: True differential measurement technology using solution ground

  • High accuracy measurements: Differential measurement technique virtually eliminates ground loop measurement error

  • No transmitter or controller required: Direct 4-20mA output for simple integration

  • Resists aggressive chemicals: Constructed of durable Ryton® Polyphenylene Sulfide (PPS)

  • Two year limited warranty: We stand behind our products with the Sensorex Guarantee


  • Measurement Range: -2000mV to +2000mV

  • Temperature Range: 0-100° C

  • Pressure Range: 0 – 100 PSIG @ 40° C (PVC fitting); 0 – 100 PSIG @ 60° C (CPVC fitting); 0 – 100 PSIG @ 100° C (stainless steel fitting);

  • Body Construction: Ryton Polyphenylene Sulfide (PPS)

  • Temperature Compensation: 300O NTC

  • Connector: Tinned Leads

  • Cable Length: 20 feet (6 meters)

  • Power Supply (not included): 12 to 30 V DC (>24 V DC recommended)

  • Installation: 1 1/2? NPT

  • Warranty: Two year limited warranty

Sensorex Process Product Brochure

Specification Sheet for SD7420 Series Differential pH and ORP Sensors with Direct 4-20mA Output

More ORP Sensors

S272CD | S465C | S651CD | S8100 | S8200 | SD7000CD | SD7420CD | SD7500CD


About Us

Metex Corporation Limited has been providing superior products and services to the process control, chemical treatment, waste water, industrial and manufacturing industries for over 25 years. It is our goal to continually provide our customers with the best possible equipment, technology, and service.


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