Endress+Hauser RMA 422 Mise En Service page 65

The following instrumentation is suitable to solve this
application:
•
2 pressure sensors, in order to measure the head
and bottom pressure.
•
Process transmitter for the power supply of both
pressure sensors, calculation of the volume using
the pressure difference as well as the output and
monitoring the head pressure and volume.
•
2 field displays front-end indication.
Calculation of the tank volume is done in three stages:
1. Transmission of the head and base pressure to the input of
the process transmitter in pressure units. Here the scaling of
the pressure sensors is done:
Menu group
IN1
Analogue input 1
(base pressure [bar])
I
N2
Analogue input 2
(head pressure [bar])
2. Calculation of the differential pressure in pressure units by
the mathematics channel:
Menu group
Mathematics channel
MATH
(differential pressure [bar])
Parameter
Input range
Curve
Measured value decimal point
Meas. value scale 0%
Meas. value scale 100%
Input range
Curve
Measured value decimal point
Meas. value scale 0%
Meas. value scale 100%
Parameter
Operator
Factor 1 decimal point
Factor 1
Factor 2 decimal point
Factor 2
Result decimal point
Process transmitter
Set-up
RANG1 4-20
CURV1 LINAR
DIDP1 999,99
DILO1 000,00
DIHI1 003,50
RANG2 4-20
CURV2 LINAR
DIDP2 999,99
DILO2 000,00
DIHI2 001,00
Set-up
MAOP SUB
FADP1 99999
FA1 00001
FADP2 99999
FA2 00001
MADP 999,99
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