hi
what is the difference of sampling period in history collection menu and scan rate that is shown in control studio?
I understand from these that, scan rate means the period that block scans the values,so if we have a change between two scans, and the value returns to its last scan time before the next scan reaches, the system will not show us, and sampling period is for trends shown in process history view so if we have change between two sampling periods, the trend does not show that and is smooth without any change.
am I right????
The scan-rate indicates the frequency of execution of the control module. This can be as fast as each 0.1 sec. At execution time, the full control module executes its algorithms (except for function blocks with scan multipliers).
The sampling period is the frequency at which the history collection reads the actual value of a parameter to decide whether this new value has to be stored.