Emerson Rosemount OCX8800A Manual page 155

Manual
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8.8.4 Signal conversion
You can set the signal conversion type with the Linearization Type (L_TYPE)
parameter. You can view the converted signal (in percent of XD_SCALE) through
the FIELD_VAL parameter.
You can choose from direct, indirect, or indirect square root signal conversion
with the L_TYPE parameter.
8.8.5 Direct signal conversion
Direct signal conversion allows the signal to pass through the accessed channel
input value (or the simulated value when simulation is enabled).
PV = Channel Value
8.8.6 Indirect signal conversion
Indirect signal conversion converts the signal linearly to the accessed channel
input value (or the simulated value when simulation is enabled) from its specified
range (XD_SCALE) to the range and units of the PV and OUT parameters
(OUT_SCALE).
8.8.7 Indirect square root
Indirect square root signal conversion takes the square root of the value
computed with the indirect signal conversion and scales it to the range and units
of the PV and OUT parameters.
When the converted input value is below the limit specified by the LOW_CUT
parameter, and the Low Cutoff in/out option (IO_OPTS) is enabled (True), a value
of zero is used for the converted value (PV). This option is useful to eliminate false
readings when the differential pressure measurement is close to zero, and it may
also be useful with zero-based measurement devices such as flow meters.
Rosemount OCX8800A
F Fieldbus
™
OUNDATION
December 2022
155