KROHNE BM 90 EN - Manual (Page 28)

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4.2. Measurement with volumetric conversion (Pr.1 = 1)
The application :
l To measure the level in a conical bottomed cylindrical tank. Dimensions as shown
l Total volume of tank = 120 m 3 when level is 8.5 m
l Output display in m 3
l Analogue output to be 0-20 mA proportional to volume in tank
l High alarm at 90 m 3 , low alarm at 10 m 3 volume
Pr. 1 = 1 Defines level measurement.
Pr. 2 = 10 Programme in meters, display/control in volume.
Pr. 3 = 9 Transducer to zero level = 9.0 m
Pr. 4 = 8.5 The span over which measurement is required.
Pr. 5 = 0.5 Blanking zone into which the level should not rise.
Pr. 6 = 10 The rate of change of level will not exceed 10.0 m/min
Pr. 8 = 1 Relay 1 to alarm on volume (normally energised)
Pr. 9 = 90 Relay 1 de-energises at 90 m 3 . High alarm on.
Pr.10 = 85 Relay 1 energises at 85 m 3 to clear high alarm.
Pr.11 = 1 Relay 2 to alarm on volume (normally energised)
Pr.12 = 10 Relay 2 de-energises at 10 m 3 . Low alarm on.
Pr.13 = 15 Relay 2 energises at 15 m 3 to clear low alarm.
Pr.30 = 3 Analogue output to be 0-20 mA fixed to span.
Pr.40 = 3 Define vessel as conical bottomed.
Pr.41 = 2.0 Define the depth of cone as 2.0 m
Pr.43 = 1.2 Define total capacity 120 m 3 .
Pr.78 Simulate the program.
9.0m
(Pr.3)
0.5m (Pr.5)
Reset Low Alarm (Pr.13)
Set Low Alarm (Pr.12)
2.0m
(Pr.41)
8.5m (Pr.4)
Reset High Alarm (Pr.10)
Set High Alarm (Pr.9)