Pressure sensors for water and wastewater applications range from submersible level transmitters in wells and tanks to network pressure monitoring and filter differential pressure. Media compatibility, drinking water certification, IP rating and installation type all need to match the specific task. This guide covers the key selection criteria and leads into the sensor selector.
Water and wastewater applications cover a wide range of measurement tasks: network pressure monitoring, pump control, filter differential pressure, level measurement in tanks and wells, flow measurement and process control in treatment plants. Each task has different sensor requirements for installation, media compatibility and output signal.
Hydrostatic level transmitters measure water depth directly in tanks, wells, rivers and reservoirs. Key requirements: vented cable, stainless or titanium housing, IP68 rating and appropriate depth range.
Pressure transmitters for water distribution networks must be robust, low-maintenance and suitable for drinking water contact. NSF 61 or KTW/WRAS certification may be required depending on the country.
Differential pressure sensors for filter monitoring, flow measurement and level in closed vessels. Low-range DP sensors for clean media; robust designs for wastewater with solids.
Wastewater contains solids, aggressive chemicals and biological content. Flush diaphragm sensors, ceramic or coated diaphragms, and resistant wetted materials are typically required.
For pressure sensors in direct contact with drinking water, material certification is typically required. The applicable standard depends on the country and utility specification.
| Standard | Region | Scope |
|---|---|---|
| NSF/ANSI 61 | USA, Canada | Materials in contact with drinking water. Commonly specified for potable water projects in North America; exact requirements depend on utility specifications and local regulation. |
| WRAS | United Kingdom | Approval route for products used in UK potable water systems. Verify whether WRAS approval or another accepted compliance route is required for the project. |
| KTW / W270 | Germany | Material suitability for potable water contact. Commonly specified in German potable water projects; exact requirements depend on the application and utility specification. |
| ACS | France | French attestation de conformité sanitaire for potable water contact materials. |
| DVGW | Germany | German gas and water association. DVGW approvals or references may be specified for components in potable water systems; verify the exact approval scope required for the sensor assembly. |
| Criterion | What to check |
|---|---|
| Media compatibility | Drinking water, treated wastewater and raw sewage have very different requirements. Verify wetted material, diaphragm type and seal material against the specific media. Chlorinated water can attack certain elastomers. |
| IP rating | IP67 or IP68 for outdoor and buried installations. Submersible sensors require IP68 suitability for permanent immersion and a pressure/depth rating that covers the maximum installation depth. Verify cable entry, connector sealing and long-term immersion specification. |
| Drinking water approval | For potable water contact, specify and verify the applicable certification — NSF 61, WRAS, KTW/W270 or ACS depending on the installation country. |
| Process connection | G1/2 and G1/4 for inline installation. Flanged for larger pipe sizes. Flush diaphragm for wastewater with solids or sludge. Submersible sensors typically use cable suspension without process connection. |
| Output signal | 4–20 mA 2-wire is most common for water and wastewater. IO-Link for smart sensor integration. Battery-powered loggers for remote or temporary installations. |
| Temperature range | Outdoor installations may require −20 °C or lower in cold climates. Wastewater treatment processes can involve elevated temperatures. Verify both ambient and media temperature ranges. |
| Submersible depth | For hydrostatic level measurement, verify the sensor depth rating and cable type. For accurate gauge measurement in open tanks and wells, a vented cable or another atmospheric pressure compensation method is typically required. |
Standard industrial pressure transmitters may not carry drinking water material certification. For potable water contact, verify NSF 61, WRAS, KTW or the applicable national standard. Material certification covers the complete wetted assembly — not just the diaphragm.
IP67 covers temporary immersion to limited depth and duration. For permanent submersible installation, use a sensor specified for IP68/permanent immersion at the required depth, with suitable cable sealing and — for gauge measurement in open tanks or wells — a vented cable or other atmospheric pressure compensation.
Wastewater containing solids, fibres or sludge can block standard diaphragm sensors. Flush diaphragm or open-ended designs with resistant coatings or ceramic diaphragms are typically more suitable for these media.
Verify before specifying: Always confirm media compatibility, drinking water certification scope, IP rating, installation depth and output signal against the manufacturer specifications. Pressure Selector provides a shortlist for further evaluation — it does not replace engineering review or certification assessment.
For promising matches, use Request Info on any result to prepare a supplier inquiry based on your application requirements.
Pressure Selector converts application requirements — such as submersible depth, IP rating, drinking water certification, media type, output signal and process connection — into a structured shortlist of matching pressure transmitters, level sensors and differential pressure sensors.
Coverage includes selected pressure transmitters, submersible level sensors and differential pressure devices for water and wastewater applications from manufacturers such as Sensata, SSI Technologies, STS, Endress+Hauser, TE Connectivity and others. Availability of NSF, WRAS, KTW and similar certifications depends on the selected series and configuration.