Function Blocks
Function Block Reference Guide
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2.60 SPP Function Block
Description
The
SPP
label stands for
Setpoint Programmer
.
This block is part of the
Setpoint Program
category. It
looks like this graphically on the Control Builder.
Function
Runs a
setpoint
ramp/soak program that produces a setpoint output on a time-based profile that is loaded
into the block. Up to 4 SPP blocks may be included in a system configuration. A single profile may be from
2 to 50 segments in length. Up to 70 profiles are stored in the controller’s memory.
Each segment of the
profile may be a ramp or soak except the last segment must be a soak.
In addition to the main ramp and soak output value, a second (AUX) analog value is available for each step
of the program. This output is a fixed soak value that may be used to provide a setpoint value for a
secondary control loop in the process. (For example, see subsection
A Setpoint guarantee function is provided that holds the program if a process variable exceeds a predefined
deviation from setpoint. Selections allow setpoint guarantee to be active for the entire program, for soak
segments only, or for user specified segments, or for no segments. (For example, see subsection
Up to 3 Process Variables may be configured as inputs to the block for setpoint guarantee.
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