CSZ EZT-570S, Руководство пользователя

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EZT-570S User Manual
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4.1.4 Setting Guaranteed Soak Events
The G-Soak selections are used to turn on the guaranteed soak option for one or more of the control
loops. To enable guaranteed soak for a loop, first press the ‘G-Soak’ button above the event list view
on the Program Entry screen. This will display the list of soak selections for each loop of the
chamber.
Figure 4-5 Program Soak Events
Press the on/off button for a loop to toggle the guaranteed soak selection on and off as desired.
When the guaranteed soak event for a loop is turned on, the program will automatically enter a hold
condition during the step if the loop’s PV deviates from its set point by more than the soak limit setting
for the loop as entered on the G-Soak Limits screen.
Guaranteed soak should not be used on ramping steps. The ramp rate will be affected if the
process variable deviates from the soak band because the program will be placed in hold.
When the program is in hold, the step length will be extended and the set points will no longer
ramp at the desired rate. Guaranteed soak should be used on soak steps to make sure that
the process stays at the desired set point, within the soak band, for the full time duration of
the step.
4.1.5 Using Wait For
The “wait” function is a powerful tool for pausing a program until a particular process variable reaches
a predefined set point. This differs from the guaranteed soak function by being a single shot monitor.
With the guaranteed soak, the process variable is monitored throughout the whole step. If the
process exceeds the upper or lower soak band, the program will pause until the process returns to
within the band. The wait for function puts the program in hold and “waits for” the process to exceed
a particular value that is set for the step. Once the process reaches this set point value, the program
will resume.
A program can also be set to wait for a digital input. This allows any of the eight optional digital inputs
to be selected. When the EZT-570S reaches the step, it will wait for the input to change state before
continuing the step.
When a guaranteed soak
selection is made on a step, an
asterisk ‘*’ will appear before
the word ‘G-Soak’ on the list
selection button.
This lets the user know that
guaranteed soak selections are
made without having to press
the ‘G-Soak’ button.