User's Manual
Table Of Contents
- Table of contents
- Important document information
- Terms and abbreviations
- Registered trademarks
- Product life cycle
- Measuring principle
- Input
- Output
- Electrical connection
- Performance characteristics
- Installation
- Environment
- Process
- Mechanical construction
- Operability
- Certificates and approvals
- Ordering information
- Accessories
- Supplementary documentation
Micropilot FMR10
Endress+Hauser V. 5, Rev. 2, 20-12-2016 7
Measuring principle
The Micropilot is a "downward-looking" measuring system, operating based on the time-of-flight
method (ToF). It measures the distance from the reference point R to the product surface. Radar
impulses are emitted by an antenna, reflected off the product surface and received again by the radar
system.
D
Q
R
100%
0%
D
L
F
E
A0028409
1 Setup parameters of the Micropilot
E Empty calibration (= zero)
F Full calibration (= span)
D Measured distance
L Level (L = E - D)
Q Flow rate at measuring weirs or channels (calculated from the level using linearization)
R Reference point
Input
The reflected radar impulses are received by the antenna and transmitted into the electronics. A
microprocessor evaluates the signal and identifies the level echo caused by the reflection of the radar
impulse at the product surface. This clear signal detection system benefits from over 30 years'
experience with time-of-flight procedures.
The distance D to the product surface is proportional to the time of flight t of the impulse:
D = c · t/2,
where c is the speed of light.
Based on the known empty distance E, the level L is calculated:
L = E – D
Output
The Micropilot is adjusted by entering the empty distance E (= zero point) and the full distance F (=
span).
• Current output: 4 to 20 mA
• Digital output (SmartBlue): 0 to 5 m (0 to 16 ft) or 0 to 8 m (0 to 26.25 ft) in combination with
accessory "flooding protection tube"