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The setpoint is the target value at which the instrument
attempts to maintain the process variable. Each loop
can have a Main “local” setpoint set from the keypad
and an Alternate setpoint.
Loop 1 Setpoint Sources
Loop 1 can have a Main “local” setpoint set from the
keypad and an Alternate setpoint. The alternate set-
point source can be either another local Setpoint or a
remote setpoint (RSP), set by a mA or V DC signal ap-
plied to the 2nd input or to auxiliary input A. The control
loop can only use one setpoint source at a time for
each loop. This is called the “Active Setpoint”. If the
profiler option is fitted this provides the setpoint when
the profiler is in use, replacing both main an alternate
setpoints.
Main/alternate setpoint selection can be made via a
digital input; from the Control Configuration menu or
if enabled in the Display Configuration sub-menu, an
operator screen can be used to select the setpoint. The
chosen setpoint selection method can be used to per-
manently select one of the setpoints, or allow switching
between them.
Refer to the Control Configuration Sub-Menu Screens
on page 50 for setpoint settings.
Loop 1 Profile Setpoint
When in profile control mode, the selected profile al-
ways provides the active setpoint source for loop 1.
Once profile control mode is exited, the selected main
or alternate setpoint for loop 1 becomes active again.
Loop 2 Setpoint Sources
Loop 2 can have a Main “local” setpoint set from the
keypad and an Alternate setpoint. The alternate set-
point source can be either another local Setpoint” or
a remote setpoint (RSP), set by a mA or V DC signal
applied to auxiliary input A. The control loop can only
use one setpoint source at a time for each loop. This
is called the “Active Setpoint”. If the profiler option is
fitted this provides the setpoint, replacing both main
an alternate setpoints, when 2-loop profiling is in use.
Main/alternate setpoint selection can be made via a
digital input; from the Control Configuration menu or
if enabled in the Display Configuration sub-menu, an
operator screen can be used to select the setpoint. The
chosen setpoint selection method can be used to per-
manently select one of the setpoints, or allow switching
between them.
Refer to the Control Configuration Sub-Menu Screens
for setpoint settings.
Loop 2 Profile Setpoint
If the selected profile was configured to control the
setpoint of both loops, it will provide the active set-
point source. Once profile control mode is exited, the
selected main or alternate setpoint for loop 2 becomes
active again.
15 Setpoint Sources
Summary of Contents for Chromalox 4081
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