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Reference Manual
00809-0100-4107, Rev BA
Section 2: Configure
April 2013
Table 2-7. Scaled Variable Configuration for Tank Application
DP Flow example
A differential pressure transmitter is used in conjunction with an orifice plate in a flow
application where the differential pressure at full scale flow is 125 inH
2
O. In this particular
application, the flow rate at full scale flow is 20,000 gallons of water per hour. It is highly
recommended to use the low flow cutoff function in order to have a stable output and avoid
problems due to process noise at a low flow or no flow condition. A low flow cutoff value that is
practical for the flow element in the application should be entered. In this particular example,
the low flow cutoff value is 1000 gallons of water per hour. Based on this information, the Scaled
Variable configuration would be as follows:
Table 2-8. Scaled Variable Configuration for Flow Application
Note
Pressure value position 1 and Scaled Variable position 1 are always set to zero for a flow
application. No configuration of these values is required.
2.8.3
Re-Mapping device variables
The re-mapping function allows the transmitter primary, secondary, tertiary, and quaternary
variables (PV, 2V, 3V, and 4V) to be configured as desired. The PV can be remapped with a Field
Communicator, AMS Device Manager, or a LOI. Variables (2V, 3V, and 4V) can only be
re-mapped via Field Communicator or AMS Device Manager.
Note
The variable assigned to the primary variable drives the 4-20mA (1-5 Vdc) output. This value
can be selected as Pressure or Scaled Variable. The 2, 3, and 4 variables only apply if HART burst
mode is being used.
Scaled Variable units:
inch
Scaled data options:
linear
Pressure value position 1:
0 inH
2
O
Scaled Variable position 1:
12 in.
Pressure value position 2:
188 inH
2
O
Scaled Variable position 2:
212 in.
Linear offset:
-209.4 inH
2
O
Scaled Variable units:
gal/h
Scaled data options:
square root
Pressure value position 2:
125 inH2O
Scaled Variable position 2:
20,000 gal/h
Low Flow Cutoff:
1000 gal/h