The timing of measurements is determined by the cycle selected during configuration: Normal or Fast Cycle:
-
Normal Cycle means that the scan cycle duration is fixed.
-
With the Fast Cycle, however, the system only scans the channels designated as being In Use. The scan cycle duration is therefore proportional to the number of channels in use.
NOTE: Filtering is disabled in Fast Cycle mode.
The Channel Scan Cycle used in Normal Cycle mode is the following:
The Channel Scan Cycle used in Fast Cycle mode is the following:
Calculating Cycle Duration
The following table provides Scan Cycle values, based on the type of cycle selected:
|
Module
|
Normal Cycle
|
Fast Cycle
|
|
TSX AEY 800
|
27 ms
|
(N+1) x 3 ms
where N = number of channels in use.
|
|
TSX AEY 1600
|
51 ms
|
(N+1) x 3 ms
where N = number of channels in use.
|
NOTE: Module cycle is not synchronized with the PLC cycle. At the beginning of each PLC cycle, each channel value is taken into account. If the MAST task cycle time is lower than the module's, some values will not have changed.
Figure:
