Endress+Hauser Levelflex M FMP40 - Page 77

Levelflex M FMP40 FOUNDATION Fieldbus Commissioning
Endress+Hauser 77
Evaluating 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.
L00-FMP40xxx-05-00-00-en-025
6.8.2 User-specific applications (operation)
For details of setting the parameters of user-specific applications, see separate documentation
BA00245F/00/EN "Description of Instrument Functions" on the enclosed CD-ROM.
400.00
400.00
400.00
[mV]
[mV]
[mV]
300.00
300.00
300.00
200.00
200.00
200.00
100.00
100.00
100.00
0.00
0.00
0.00
-100.00
-100.00
-100.00
-200.00
-200.00
-200.00
-300.00
-300.00
-300.00
-400.00
-400.00
-400.00
-500.00
-500.00
-500.00
0.00
0.00
0.000.20
0.20
0.200.40
0.40
0.400.60
0.60
0.600.80
0.80
0.801.00
1.00
1.00[m]
[m]
[m]
LN
LN
LNE
E
EF
F
F
(1.00 m, -143.00 mV)
(0.98 m, 0.00 mV)
(0.99 m, -137.94 mV)
Launch pulse
Negative
probe end signal
Envelope curve
Differential curve = Envelope curve Mapping
Mapping