Future Design MCTB 4.3, Руководство пользователя

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MCTB
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all inputs reach the wait set point, the step time countdown will resume and not be held up again for the
remainder of the step.
NOTE: For proper holdback operation, a minimum step time of 10 seconds 0.10 (mm:ss) or 1 minute 0.01
(hh:mm) is required to ensure that the holdback condition can recognize the process change in order
for holdback to operate. If the step time is less than 10 seconds, the holdback condition may not be
triggered.
6.1.5.1 HoldBack Limits
The holdback limit settings are used to set the control tolerance for each loop during steps that have hold back
enabled. When the loop process variable deviates from its set point by more than the band value (above or
below set point), the program timer will stop until the process variable re-enters the hold back band. The
Holdback Limits are accessed from the Edit pop-up menu. The entries apply to every step in the program and
only need to be entered once for the program.
The MCTB uses “band” type holdback operations. This means the MCTB will be in hold mode when the loop
process value is above or below the loop set point by the entered holdback limit value during step operation.
Holdback steps must have a minimum value of .10 (mm:ss) or .01 (hh:mm) for holdback to engage during the
step. A time value of 0 in a holdback step will cause the automated program to continue to the next step and
skip the holdback step.
When at least one hold
condition set in a step, an
asterisk ‘*’ will appear before
the word
“Hold” on the list
selection button.
This indicates that holdback
or wait for is enabled on at
least
one input without
having to press the
“Hold”
button to view the list
selections.