Endress+Hauser Levelflex M FMP40, Руководство по эксплуатации

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Technical data Levelflex M FMP40 with HART/4...20 mA
76 Hauser
Cleaning the probe Depending on the application, contamination or buildup can accumulate on the probe. A thin, even
layer only has a slight impact on the measurement. Thick layers can dampen the signal and then
reduce the measuring range. Severe, uneven buildup, adhesion e.g. through crystallization, can lead
to incorrect measurement. In such instances, we recommend you use a non-contact measuring
principle, or check the probe regularly for fouling.
Electromagnetic compatibility
(EMC) Electromagnetic compatibility to EN 61326 and NAMUR Recommendation EMC (NE21). Details
are provided in the Declaration of Conformity.
A standard installation cable is sufficient if only the analog signal is used. Use a shielded cable when
working with a superimposed communication signal (HART).
When installing the probes in metal and concrete tanks and when using a coax probe:
• Interference emission to EN 61326 - x series, Class A equipment.
• Interference immunity to EN 61326 - x series, requirements for industrial areas and NAMUR
Recommendation NE 21 (EMC)
The measured value can be affected by strong electromagnetic fields when installing rod probes
without a shielding/metal wall, e.g. plastic, and in wooden silos.
• Interference emission to EN 61326 - x series, Class A equipment.
• Interference immunity: the measured value can be affected by strong electromagnetic fields.
10.1.5 Operating conditions: process
Process temperature range The maximum permitted temperature at the process connection (see Figure for measuring point) is
determined by the O-ring version ordered:
!
Note!
The medium temperature can be higher.
The metal uninsulated probes are only insulated in the area of the bushing. Thus, there is no danger
of electrostatic charging.
O-ring material Min. temperature Max. temperature
1)
1) For PA-coated probes, the maximal admissible temperature is 100 °C.
FKM (Viton) -30 °C +150 °C
EPDM -40 °C +120 °C
FFKM (Kalrez) -5 °C
2)
2) The min. temperature of FFKM can be -15 °C if the max. temperature of +80 °C is not exceeded.
+150 °C
measured
here