Setpoint Programmers; Overview; Description; Table 35 Spp Inputs And Current State - Honeywell 900 User Manual

Overview

Description

A setpoint programmer supplies a time-varying setpoint to a control loop. A program contains multiple
segments; each segment can be a ramp or a soak and has digital switches called "events." This menu lets
you edit setpoint program segments, segment events, or other parameters and save the changes to the
controller's memory.
Each program contains multiple segments. Each segment of the program may be a ramp or soak except the
last segment must be a soak.
Multiple programs can be running concurrently. Programmers can run any of the profiles in controller
memory. Once loaded from memory into the Setpoint Programmer (SPP) function, these profiles are
referred to as "programs." Any program can be edited and saved as a profile in one of the "slots" in the
controller's memory.
In addition to the main output value, a second analog value is available for each step of the program. This
output is a fixed soak value, which may be used as an input to another function or to provide a setpoint
value for a secondary control loop in the process.
A Setpoint guarantee function (known as guaranteed hold) 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.
Up to 3 Process Variables may be configured as inputs to the block for setpoint guarantee.
The program may be changed (with some exceptions) from the current state to a new state by the operator
as well as by inputs to the SPP block. Table 35 lists the resulting states.
Input
RESET
HOLD
RUN
GHOLD
With regard to changing program state, if more than one function block input is on in the same execution
cycle, RESET has priority over HOLD and RUN, and GHOLD has priority over RUN.
Also, function block inputs will override inputs from the Control Station, which occur during the same
execution cycle. Finally, state changes from the Control Station are processed on the basis of the "last
change wins."
Revision 9
May 2014

Setpoint Programmers

Table 35 SPP inputs and current state

READY HOLD
READY READY
HOLD HOLD
RUN RUN
READY HOLD
900 Control Station User Guide
Current State
RUN GHOLD
RUN READY
HOLD HOLD
RUN GHOLD
GHOLD GHOLD

Setpoint Programmers

Overview
STOP
READY
STOP
STOP
STOP
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