Waterpilot FMX21 - hydrostatic level probe

Reliable hydrostatic level measurement for drinking water, wastewater and saltwater applications

FMX21

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5-year warranty

Engineered for Confidence

Our Fundamental Selection instruments feature an extended 5-year warranty – a clear testament of our trust in their long-term reliability and performance.

Should a warranty case occur, you can count on a fast replacement process and minimal administrative effort – giving you peace of mind when it matters most and helping you keep your operations running smoothly.

Warranty terms apply

The extended warranty is subject to specific conditions. For full details, please refer to the locally applicable General Terms and Conditions (GTC), which can be found on the respective country page of our website.

Waterpilot FMX21 with stainless steel housing for drinking water applications

Detail view of Waterpilot FMX21 with stainless steel housing for drinking water applications

Waterpilot FMX21 with stainless steel housing for wastewater applications

Waterpilot FMX21 with plastic insulation for saltwater applications

Specs at a glance

Accuracy

0.2%
0.1% (optional)
Process temperature

-10°C...70°C
(14°F...158°F)
Diameter 29 mm (1.14"): 0°C...50°C
(32°F...122°F)
Pressure measuring range

100 mbar...20 bar
(1.5 psi...300 psi)
Main wetted parts

Diameter 22 mm and 42 mm: Seal, 316L, Ceramic
Diameter 29 mm: Seal, PPS, Polyolefin, Ceramic
Extension cable: PE, PUR, FEP
Max. measurement distance

200 m H2O
(656 ft H2O)
Measuring cell

100mbar...20bar
(1.5psi...300psi)

See all specifications

Field of application

Waterpilot FMX21 is a robust hydrostatic level probe featuring an oil‑free capacitive ceramic measuring cell for stable and accurate measurement results. Freely adjustable measuring ranges can be configured via HART, enabling flexible adaptation to different process requirements in drinking water, wastewater and saltwater applications. An optionally integrated temperature sensor enables simultaneous measurement of level and temperature.

Available in three versions for drinking water, wastewater and saltwater applications, Waterpilot FMX21 is supported by international explosion protection certificates, marine and drinking water approvals. It is suitable for use in a wide range of applications, including:

Deep and narrow drinking water wells and boreholes
Process and storage tanks in water and wastewater applications
Saltwater and marine tanks, e.g. ballast water tanks
Rivers, lakes and reservoirs for environmental monitoring

Benefits

Robust design with an oil-free capacitive ceramic measuring cell for long‑term operation
Easy system integration and flexible parameterization via HART communication
Geometry‑independent hydrostatic level measurement, ideal for deep, narrow boreholes and wells
Compliance with international explosion protection certificates, marine approvals and drinking water certifications
Optionally integrated temperature sensor enables temperature‑compensated density correction for high measurement accuracy

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Predecessor

Waterpilot FMX167

Success stories

Reliable flow measurement in open channels

Ensure compliance and efficiency with FlexView FMA90 and Micropilot FMR20B
Read the full story
Saving energy with smart e-boiler monitoring

Boosting sustainability with real-time energy insights
Read the full story
Safe and easy access to process data via Bluetooth

Kemira, a global chemicals company, needs accurate monitoring of level and temperature for polymer manufacturing. They use instrumentation with Bluetooth for safe and easy access to process data.
Read the full story
Effective seal pot monitoring

Global agricultural innovator Nufarm has successfully trialled the installation of level and pressure instrumentation on its seal pots for early identification of issues with the mechanical seal.
Read the full story
Driving accuracy in space propulsion

Protolaunch uses Endress+Hauser flowmeters and level sensors at a rocket propulsion test facility in Buckinghamshire to demonstrate the performance of the propulsion systems and components.
Read the full story

Simple products
Easy to select, install and operate

Technical excellence

Simplicity

What is FLEX?

Standard products
Reliable, robust and low-maintenance

Technical excellence

Simplicity

What is FLEX?

High-end products
Highly functional and convenient

Technical excellence

Simplicity

What is FLEX?

Specialized products
Designed for demanding applications

Technical excellence

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Variable

What is FLEX?

FLEX selections	Technical excellence	Simplicity
F L E X Fundamental selection Meet your basic measurement needs	Technical excellence	Simplicity
F L E X Lean selection Handle your core processes easily	Technical excellence	Simplicity
F L E X Extended selection Optimize your processes with innovative technologies	Technical excellence	Simplicity
F L E X Xpert selection Master your most challenging applications	Technical excellence	Simplicity Variable

Learn more about the FLEX selections

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25/01/2023

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12/04/2012

Waterpilot FMX21 - hydrostatic level probe

Reliable hydrostatic level measurement for drinking water, wastewater and saltwater applications

Specs at a glance

Accuracy

Process temperature

Pressure measuring range

Main wetted parts

Max. measurement distance

Measuring cell

Field of application

Benefits

Predecessor

Success stories

Reliable flow measurement in open channels

Saving energy with smart e-boiler monitoring

Safe and easy access to process data via Bluetooth

Effective seal pot monitoring

Driving accuracy in space propulsion

Measuring principle

Characteristic

Supply voltage

Reference Accuracy

Long term stability

Process temperature

Ambient temperature

Measuring cell

Process connection

Communication

Certificates / Approvals

Marine approvals

Drinking water approvals

Measuring principle

Characteristic / Application

Specialities

Supply / Communication

Accuracy

Long term stability

Ambient temperature

Process temperature

Pressure measuring range

Main wetted parts

Process connection

Max. measurement distance

Communication

Certificates / Approvals

Marine approval

Drinking water approvals

Options

Application limits

Back

TI Waterpilot FMX21

BA Waterpilot FMX21

BA Waterpilot FMX21

KA Waterpilot FMX21 HART

Waterpilot FMX21

KA Waterpilot FMX21

Waterpilot FMX21

Suspension clamp

Pressure adapter Installation instruction

Waterpilot FMX21

Back

Pressure compensation Waterpilot

Protection press.sensor Waterpilot, 5pc.

Protection cover, PFA

Mounting clamp FMX21, FMX11, 316L

Additional weight FMX21, FMX167, 316L

Cable-mounting-screw G1-1/2, 304

Binding posts terminal box FMX21, FMX167

Cable-mounting-screw NPT1-1/2, 304

Test adapter FMX21, FMX167

Shorten.kit extension cable FMX21,FMX167

Terminal box 120x80x55, PC

HART communication resistor Ex/non Ex

Transmitter 2-wire TMT71 -20/+80oC

Transmitter 2-wire TMT72 HART -20/+80oC

Input

Output

Display

Power Supply

Input