Digital pH Measurement for Demanding Chemical Processes
The Memosens CPS71E is designed for pH measurement where conventional sensors can face contamination, poisoning, or rapidly changing process conditions.
Its special reference system incorporates an ion trap to improve resistance to electrode poisons. This makes the CPS71E particularly suitable for chemical processes involving media with a high proportion of substances such as H₂S, as well as applications where pH values change rapidly.
The sensor uses a gel compact electrode with a ceramic junction and ion trap, combined with advanced gel technology and an integrated temperature sensor.
Memosens 2.0 for Easier Sensor Management
The CPS71E uses Memosens 2.0 with an inductive, contactless connection. Measurement and sensor data are transferred digitally, while calibration and process information can be stored directly in the sensor.
This allows the sensor to be pre-calibrated in the laboratory and exchanged quickly at the measuring point, helping simplify maintenance and reduce process downtime. The stored data also provides a basis for condition monitoring and predictive maintenance.
Resistant to Contaminated and Aggressive Media
One of the key advantages of the CPS71E is its contamination-resistant reference system. The ion trap helps protect the reference system from electrode poisons, making the sensor suitable for difficult process media where conventional pH electrodes may experience faster contamination or shortened calibration intervals.
This makes it particularly useful for chemical production and other industrial processes involving aggressive media or high levels of contaminants.
Key Technical Highlights
- Measuring range: pH 0 to 14 for Application B
- Measuring range: pH 0 to 12 for Application H
- Measuring principle: Potentiometric
- Electrode design: Gel compact electrode with ceramic junction and ion trap
- Process temperature: 1 to 140 °C
- Process pressure: 0.8 to 14 bar absolute
- Diameter: 12 mm
- Available shaft lengths: 120, 225, 360 and 425 mm
- Temperature sensor: NTC 30k
- Connection: Inductive, contactless Memosens 2.0
- Ingress protection: IP68
- Reference system: Contamination-resistant reference with ion trap
- pH membrane glass: Type B / Type N
- Sensor shaft: Glass suitable for the process
- Process coupling: PPS fiber-glass reinforced
- O-ring: FKM
- Ex approvals: ATEX, IECEx, CSA C/US, NEPSI, Japan Ex and INMETRO for applicable configurations
Typical Applications
Chemical Processing
The CPS71E is designed for pH measurement in chemical processes where aggressive media, contamination, and electrode poisoning can affect conventional sensors.
Processes with H₂S and Electrode Poisons
The ion-trap reference system makes the sensor particularly suitable for applications with a high proportion of electrode poisons such as H₂S.
Rapidly Changing pH Processes
The CPS71E is suitable for process monitoring where pH values can change quickly and reliable digital measurement is required.
Hazardous Areas
Selected configurations are available with ATEX, IECEx, CSA C/US, NEPSI, Japan Ex and INMETRO approvals for hazardous areas including Zones 0, 1 and 2.
Frequently Asked Questions
What is the Endress+Hauser CPS71E used for?
The CPS71E is a digital pH sensor designed primarily for chemical processes and demanding applications with aggressive or heavily polluted media. It is particularly suitable for processes containing electrode poisons such as H₂S or processes with rapidly changing pH values.
What is the measuring range of the CPS71E?
The CPS71E has two application-dependent measuring ranges:
Application B: pH 0 to 14
Application H: pH 0 to 12
What is the operating temperature of the CPS71E?
The specified process temperature range is 1 to 140 °C (32 to 284 °F).
What makes CPS71E different from a standard pH sensor?
The CPS71E is specifically designed for difficult chemical processes. Its contamination-resistant reference with ion trap provides improved resistance to electrode poisons and heavily polluted media.
It also uses Memosens 2.0, allowing sensor data and calibration information to be stored directly in the sensor.
Does CPS71E use Memosens 2.0?
Yes. The CPS71E uses an inductive, contactless Memosens 2.0 connection, providing digital data transmission and sensor data storage.
Can CPS71E be used in hazardous areas?
Yes. Applicable configurations have approvals including ATEX, IECEx, CSA C/US, NEPSI, Japan Ex and INMETRO for hazardous areas. The exact approval depends on the selected sensor configuration.
What shaft lengths are available?
The CPS71E is available with shaft lengths of 120, 225, 360 and 425 mm, with a sensor diameter of 12 mm.
What temperature sensor is integrated into CPS71E?
The CPS71E uses an integrated NTC 30k temperature sensor for temperature measurement and compensation.
Can the CPS71E be pre-calibrated before installation?
Yes. With Memosens technology, the sensor can be pre-calibrated in the laboratory and exchanged at the measuring point, helping simplify maintenance and reduce process downtime.
