Orbitex W CPS21

Summary

Product identification

• Product Name: Orbitex W CPS21
• Product Type: pH sensors with open ring junction for wastewater technology
• Document: TI00029C/07/EN/12.22-00

Application

• Municipal wastewater
• Electroplating wastewater
• Wastewater from metal processing plants

Your benefits

• Resistant to blocking media, quick response time and reliable measurement thanks to open ring junction.
• Can be used under pressures up to 6 bar (87 psi) without counterpressure thanks to solid Polytex electrolyte.
• Long service life due to optimized diffusion path of 180 mm (7.09 in) and thus a long poison diffusion path of the reference system.
• TOP68/ESA plug-in head, water proof (IP 68).

Measuring principle

pH measurement

The pH value is a measure of acidity or alkalinity. The sensor's membrane glass generates an electrochemical potential based on the medium's pH. An integrated Ag/AgCl reference system serves as the reference electrode. The measured voltage is converted to a pH value using the Nernst equation.

Measuring system

A complete measuring system typically includes:

• CPS21 pH sensor
• Transmitter (e.g., Liquiline CM42)
• Measuring cable (e.g., CPK9)
• Immersion or flow assembly (e.g., Dipfit CPA111)

Input

• Measured variables: pH value, Temperature
• Measuring range:
  • pH: 2 to 12
  • Temperature: –15 to 60 °C (5 to 140 °F)

Electrical

• Energy supply: Memosens sensors, sensors with TOP68 plug-in head, sensors with GSA plug-in head. Specific connection details depend on the measuring cable (CYK10, CYK20, CPK9, CPK1).

Installation

• Orientation: Sensors should not be installed upside-down.
• Angle of inclination: Must be at least 15° from the horizontal to ensure the pH membrane is covered with inner electrolyte.
• Assembly mounting: Hand-tighten sensor to 3 Nm (2.21 lbf ft) when installing in Endress+Hauser assemblies. Ensure threads, O-rings, and sealing surfaces are clean and undamaged.

Environment

• Operating temperature range: –15 to 60 °C (5 to 140 °F)
• Storage temperature: 0 to 50 °C (32 to 122 °F)
• Degree of protection:
  • IP 67: GSA plug-in head (with closed connector system)
  • IP 68: TOP68 plug-in head, up to 135 °C (275 °F) (1 m (3.3 ft)) water column, 50 °C (122 °F), 168 h.
• Electromagnetic compatibility (EMC): Interference emission and interference immunity as per EN 61326: 2012.

Process

• Process temperature range: –15 to 60 °C (5 to 140 °F)
• Process pressure range: 0 to 6 bar (0 to 87 psi)
• Conductivity: Min. 500 µS/cm

Mechanical construction

• Design, dimensions:
  • Overall length: 120 mm (4.70 in)
  • Diameter: ø 12 mm (0.47 in)
• Weight: 0.1 kg (0.2 lb)
• Materials:
  • Electrode shaft: Glass
  • pH membrane glass: Type A
  • Metal lead: Ag/AgCl
  • Diaphragm: Open ring junction
  • Temperature sensor: Integrated
  • Plug-in head:
    • ESA: Threaded plug-in head Pg 13.5, TOP68, 16 bar (232 psi) overpressure protection (threefold)
    • GSA: Threaded plug-in head Pg 13.5
• Reference system: Ag/AgCl with Polytex gel 3M KCl, AgCl-free.
• Process connections: Pg 13.5

Certificates and approvals

Available certificates and approvals can be selected via the Product Configurator on www.endress.com.

Ordering information

• Product page: www.endress.com/cps21
• Use the Product Configurator to configure and obtain a valid order code. CAD drawings may be available.

Scope of delivery

• Ordered version of the sensor
• Operating Instructions
• Safety instructions (if Ex approval ordered)
• Supplementary sheet for certificates (if ordered)

Accessories

• Assemblies: Dipfit CPA111, Dipfit CPA140, Flowfit CPA240, Flowfit CYA27, Ecofit CPA640.
• Buffer solutions: CPY20.
• Measuring cable: CPK9, CPK12, CPK1.

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Disclaimer: This extraction may miss figures, footnotes, or revisions. Contractual data must match the OEM PDF revision used on the project.

Official datasheet (PDF)

Lenntech datasheet mirror