User Manual

Data storage
Data transfer processes
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● Improves performance
● Is faster than full code generation
Online loading
The full download transfers all loadable units into the automation station.
The delta download:
● Copies additional blocks into the automation station
● Deletes blocks which are no longer valid
● Updates parameter settings
The delta download is faster than a full download. You do not need to interrupt
the operation of the automation station.
The delta download helps prevent unintentional parameter changes. Online
changed process data and settings parameters are protected against
unintentional overwriting, provided the process data was not changed in the
tool.
You can define what happens in the automation station before and after the
download. You can define if:
● Parameters are read back before the download
● The program starts and/or the I/O bus is turned on after the download
Online readback
During readback of non-volatile process values and parameter settings the data
in the automation station is aligned with the project data in the tool.
Readback comprises two steps:
1. Current parameter settings and non-volatile process values in the PX/PXC3
automation station are read from the automation station and copied to the
data storage.
2. The values are updated in the CFC data storage or PXC3 program and
configuration data storage.
The following data can be read back from PX/PXC3 to the project data storage
in the XWP/ABT tools:
● Setting parameters changed in the PX/PXC3 automation station
● Changed, non-volatile process values or configuration data
Reading back data has the following advantages:
● Outdated data in XWP/ABT is overwritten by current data and thus is
available again for reloading programs in the PX/PXC3 automation station.
● During online changes of background variables (e.g., calendar), data
between CFC and XWP/ABT and the automation station is retained.
● Current setting parameters and non-volatile process values (e.g., operating
hours) are saved.
● The newest configuration is saved offline and can be used for, e.g., reports.
Runtime data cannot be read back. Only offline data can be read back. Only
objects (not individual properties) can be read back. If a property is changed,
the entire object (e.g., data point), that is, the last change on the object is read
back. The last change per object is always valid.
There are two workflows for changes:
Workflow 1 (ideal workflow):
1. Perform readback before the changes
2. Perform changes offline
3. Download
Workflow 2:
1. Perform changes offline
2. Perform readback
Full download
Delta download
Download options
Advantages
Workflows for changes