Simatic 505 SoftShop
9 - PID Loops
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151
A PV alarm deadband is provided to minimize cycles in and out of alarm
(chattering) that generate large numbers of messages when the PV hovers
near one of the alarm limits.
An option is also available to call a Special Function Program to initiate a
special function calculation. The SF program call can be scheduled on the
PV, the SP, or the output.
Programming PID Loop
The PID Loop Editor gives you the ability to display, access, and/or
modify PID Loops.
To access the PID Loop Editor:
1.
Click PID Loop from the View menu (Alt+V,P).
2.
The PID Loop Directory dialog box appears (Figure 9.1a).
3.
The dialog box shows the Loop Mode, Loop number (1-512 )
depending on the processor type, Loop Title, and
Enable/Disable state.
Figure 9.1a
4.
Select the PID Loop number that you want to enter or edit by
using the left mouse button or the Arrow keys on the keyboard.
5.
To edit the selected PID Loop number, double-click on the Loop
number or click on the dialog box Edit button, or use the
keyboard to Tab to the Edit button and press Enter or (Alt + E).
The following dialog box appears (see Figure 9.2).