Future Design MCTB 4.3, Руководство пользователя

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MCTB
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The name of the running program, or current program loaded to the MCTB loop controls, will be shown at the
bottom center of the screen. If no program has been loaded, the field will be empty.
IMPORTANT: If the set point does not match the set point programmed for the step, check the set point limits
for the loop (see section 9.3 Setpoint Limits ). The lower and upper limits define the allowed
operating range. If a step set point exceeds a limit, it will be coerced to the lower or upper limit
that it exceeds. This is done automatically without altering the original program.
6.4 Common Questions About Ramp/Soak Program Operation
1. How do I start or run a ramp/soak program?
To select and start a program, use the Program Operation window which can be accessed from the Loop, To
select and start a program, use the Program Operation window which can be accessed from the Loop, Overview
or program Entry screens. All start, stop, hold, edit and program select operations are available from this
window.
2. How do I know which program is running?
When a program is running, the name is displayed on program Status view screen as well as the Loop and
Overview screens. It is also shown on the Program Operation window. The MCTB will indicate that the program
is running when it is in operation. If a program is not running, the MCTB will display the name of the currently
loaded program, i.e., present in memory and ready to be run.
3 Why is the program not running to the set point entered for the step?
Automatic ramp/soak program operation is limited by the lower and upper set point limits (see section 9.3
Setpoint Limits ). If a program step has a set point that exceeds the lower or upper limit, the set point will be
automatically coerced to the limit it exceeds. This prevents damage to equipment or product by ensuring that
the system only operates to the range entered by the user. If a program step has a set point of 100 for example,
but the upper limit is 90, when the program is run the set point will be coerced to the maximum allowed upper
limit of 90 during operation of the step.
The original program remains unaltered, so if the user then changes the lower and upper limits to match the
range of set points within the program, the program will then operate to the programmed set points. This
ensures that the operating range of the system cannot be exceeded even if a user accidentally copies a program
from another system with a greater operating range.
4 Why is the program not coming out of a Wait For hold condition?
When a wait condition is applied to a step, the step will not begin until the wait condition is met. When using a
wait condition to initiate a soak step, be sure to place the wait condition on the soak step. If the wait is applied
to the ramp step, the program will not continue because the set point will not change until the wait condition is
met, i.e., the ramp cannot take place until the step is executed. Since the set point does not change, the input
will not change to meet the wait set point and the program will wait indefinitely.