Emerson Rosemount 3051CF Series Reference Manual page 23

Reference Manual
00809-0100-4774
Note
Typically, instrument personnel configure the channel, Set XD_Scale, Set L_Type, and
sometimes Set Out_Scale. The control systems configuration engineer configures other AI
block parameters, block links, and schedule.
Input selector block
You can use the input selector (ISEL) function block to select the first good, Hot Backup
maximum, minimum, or average of as many as eight input values and place it at the
output. The block supports signal status propagation.
Integrator block
The integrator (INT) function block integrates one or two variables over time. The block
compares the integrated or accumulated value to pre-trip and trip limits and generates
discrete output signals when the limits are reached.
The INT block is used as a totalizer. This block will accept up to two inputs and has six
options to totalize the inputs and two trip outputs.
Arithmetic block
The arithmetic (ARTH) function block provides the ability to configure a range extension
function for a primary input. You can also use it to compute nine different arithmetic
functions, including flow with partial density compensation, electronic remote seals,
hydrostatic tank gauging, ratio control, and others.
Signal characterizer block
The signal characterizer (SGCR) function block characterizes or approximates any function
that defines an input/output relationship. The function is defined by configuring as many
as 20 X,Y coordinates. The block interpolates an output value for a given input value using
the curve defined by the configured coordinates. You can process two separate analog
input signals simultaneously to give two corresponding separate output values using the
same defined curve.
PID block
The PID function block combines all of the necessary logic to perform proportional/
integral/derivative (PID) control. The block supports mode control, signal scaling and
limiting, feed forward control, override tracking, alarm limit detection, and signal status
propagation.
The block supports two forms of the PID equation: standard and series. You can select the
appropriate equation using the MATHFORM parameter. The standard ISA PID equation is
the default selection.
Control selector block
The control selector (CSEL) function block selects one of two or three inputs to be the
output. The inputs are normally connected to the outputs of PID or other function blocks.
One of the inputs would be considered normal and the other two overrides.
Reference Manual
Configuration
July 2020
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