Future Design MCTB 4.3, Руководство пользователя

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MCTB
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Once the loop is at its target set point, the target set point will be removed and only the normal PV/SP
information will be provided. Thus, the only indication a loop is configured for ramp rate operation on the
Overview screen, is when it is actively ramping to a set point.
IMPORTANT: On power up, and each time the user transitions from offline settings to online operation, each
loop that is configured for ramp rate will restart ramping operation from the current process
value to the last target set point provided regardless as to whether it had reached set point
prior to entering offline mode. This ensures that the user entered rate of change is maintained
when the MCTB resumes control of the system.
If automatic ramp/soak program operation is utilized with loops configured for ramp rate
operation, the program will override the user entered rate up/down limits. The loop set points
will be defined by the program. Thus, it is up to the user to ensure that the program is written
properly so that it does not exceed the maximum desired rate of change for the loop set point.
5.5.1.2
Setpoint 2 Operation (MCTB 4.3” version 4MA V1.3 only)
A secondary set point can be configured for a loop and activated via the
loop’s event input. The secondary set
point can be either an actual set point value, or a deviation offset from the current user or program defined set
point the loop is currently operating under (see section
4.2.39 Setpoint 2 Format
(MCTB 4.3” version 4MA V1.3
only)
). When set point 2 is activated, the “SP” tag label on the main Loop View screen will indicate that set
point 2 is active by displaying “S2”.
Pressing the SP tag label will display a dia
log indicating the current user (or program) set point shown as “S1”.
The Overview screen will also indicate that the loop is under set point 2 operation and via the “S2” tag
designation for the set point while displaying the user (or program) set point S1 in parenthesis.