Endress+Hauser Levelflex M FMP45 Operating Instructions Manual page 63

Levelflex M FMP45 with HART/4...20 mA
Endress + Hauser
Evaluation of the measurement:
• The map must correspond to the course of the envelope curve (for rod probes up to approx. 5 cm
and for rope probes up to approx. 25 cm before the end of the probe) when the tank is empty.
• Amplitudes in the differential curve should be at a level of 0 mV when the tank is empty and lie
within the span that is specified by the probe-specific blocking distances. In order to not detect
any interference echoes, there must be no signals that exceed the echo threshold when the tank
is empty.
• For partially-filled tanks, the map may only differ from the envelope curve at the position of the
level echo. The level signal is then detected unequivocally as a positive signal in the differential
curve. For detecting the level echo, the amplitude must lie above the echo threshold.
[mV]
400.00
300.00
200.00
100.00
0.00
Negative
-100.00
probe end signal
-200.00
-300.00
Launch pulse
-400.00
F
-500.00
0.00 0.20 0.40 0.60
Envelope curve
Differential curve = Envelope curve Mapping
6.8.3 User-specific applications (operation)
For details of setting the parameters of user-specific applications, see separate documentation
BA245F – "Description of the instrument functions" on the enclosed CD-ROM.
[mV]
400.00
300.00
200.00
100.00
0.00
-100.00
(1.00 m, -143.00 mV)
-200.00
-300.00
-400.00
E LN
-500.00
0.80 1.00 [m] 0.00
[mV]
400.00
300.00
200.00
100.00
0.00
-100.00
-200.00
-300.00
-400.00
F
-500.00
0.00 0.20 0.40 0.60
Commissioning
F
0.20 0.40 0.60 0.80
Mapping
(0.98 m, 0.00 mV)
E LN
0.80 1.00 [m]
L00-FMP40xxx-05-00-00-en-025
(0.99 m, -137.94 mV)
E LN
1.00 [m]
63