Endress+Hauser Hart Cerabar PMP71B, Operating Instructions Manual

Page: 46 / 84

Commissioning Cerabar PMP71B HART
46 Hauser
9.7.4 Linearization
In the following example, the volume in a tank with a conical outlet should be measured in
m 3 .
Prerequisites:
• Points for linearization table are known
• Level calibration is performed
• Linearization characteristic must continually increase or decrease
L
WARNING
The settings of the current output are relevant for safety!
This can result in product overflow.
‣
The setting for the current output depends on the setting in the Assign PV parameter.
‣
After changing the setting for the current output, check the setting for the span (LRV
and URV) and readjust it if necessary!
h
[m]
0
0 3.0
3.5
V
[m
3
]
V
[m ]
3
20
4
0 3.5
I
[mA]
A0038910
1. In the Assign PV parameter, the Scaled variable option must be set
 Menu path: Application → HART output → HART output → Assign PV
2. In the Scaled variable unit parameter, set the desired unit
 Menu path: Application → Sensor → Scaled variable → Scaled variable unit
3. The linearization table can be opened via the Go to linearization table
parameter Table option.
 Menu path: Application → Sensor → Scaled variable → Scaled variable transfer
function
4. Enter the desired table values.
5. The table is activated once all the table points have been entered.
Result:
The measured value after linearization is displayed.
• Error message F435 "Linearization" and the alarm current appear as long as the
table is being entered and until the table is activated
• The 0% value (= 4 mA) is defined by the smallest point in the table
The 100% value (= 20 mA) is defined by the largest point in the table
• The assignment of the volume/mass values to the current values can be changed
with the Lower range value output parameter and Upper range value output
parameter