Endress+Hauser Prosonic M FMU41 - Performance Characteristics; Reaction Time; Reference Operating Conditions; Measured Value Resolution

Prosonic M
14 Endress+Hauser
Performance characteristics
Reaction time The reaction time depends on the parameter settings. The minimum values are:
• 2-wire devices (FMU40/41/42): min. 2 s
• 2-wire diveces (FMU43 - PROFIBUS PA or FOUNDATION Fieldbus): min. 2 s
• 2-wire devices (FMU44): min. 3 s
• 4-wire devices (FMU40/41/42/43/44): 0.5 s
Reference operating
conditions
• Temperature = +20 °C (68 °F)
• Pressure = 1013 mbar abs. (15 psi abs.)
• Humidity = 50 %
• Ideal reflective surface (e.g. calm, smooth fluid surface)
• No interference reflections within signal beam
• Set application parameters:
– Tank shape = flat ceiling
– Medium property = liquid
– Process conditions = calm surface
Measured value resolution
Pulse frequency • 2-wire devices (FMU40/41/42): max. 0.5Hz
• 2-wire devices (FMU43 - PROFIBUS PA or FOUNDATION Fieldbus): max. 0.5 Hz
• 2-wire devices (FMU44): max. 0.3 Hz
• 4-wire devices (FMU40/41/42/43/44): max. 2Hz
The exact values are dependent on the type of device and the parameter settings.
Measuring error Typical specifications for reference operating conditions (include linearity, repeatability, and hysteresis):
1
whichever is greater
Influence of the vapor
pressure
The vapor pressure at 20 °C (68 °F) gives a hint on the accuracy of the ultrasonic level measurement. If the
vapor pressure at 20 °C (68 °F) is below 50 mbar (1 psi), ultrasonic level measurement is possible with a very
high accuracy. This is valid for water, aqueous solutions, water-solid-solutions, dilute acids (hydrochloric acid,
sulfuric acid, ...), dilute bases (caustic soda, ...), oils, greases, slurries, pastes, ...
High vapor pressures or outgassing media (ethanol, acetone, ammonia, ...) can influence the accuracy. If
conditions like these are present, please contact your Endress+Hauser sales representative.
Sensor Measured value resolution
FMU40 1 mm (0.04 in)
FMU41 1 mm (0.04 in)
FMU42 2 mm (0.08 in)
FMU43 2 mm (0.08 in)
FMU44 2 mm (0.08 in)
Sensor Measuring error
FMU40 ±2 mm (0.08 in) or 0.2% of set measuring distance (empty calibration)
1
FMU41 ± 2 mm (0.08 in) or 0,2% of set measuring distance (empty calibration)
1
FMU42 ± 4 mm (0.16 in) or 0,2% of set measuring distance (empty calibration)
1
FMU43 ± 4 mm (0.16 in) or 0,2% of set measuring distance (empty calibration)
1
FMU44 ± 4 mm (0.16 in) or 0,2% of set measuring distance (empty calibration)
1