Setting Retentivity - Siemens SIMATIC S7-1500 Getting Started

Software section
3.2 Creating the program
3.2.10

Setting retentivity

Introduction
All tags are initialized with their configured start values during CPU startup, for example,
after a power failure. The most recent values the tags had immediately before the
interruption are overwritten with the initial values. To prevent this, define the tag as retentive.
Retentive tags retain their values even after a restart.
In this example, the levels of paint storage tanks are backed up in the retentive memory area
of the CPU.
Procedure
1. Connect to the CPU online.
2. Enable the retentivity for the "Cyan" entry in the "Filling" data block.
3. Load the change to the CPU.
4. Drag the "Watchtable" object from the library into the project. This object contains the fill
level tags included a control value.
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Getting Started, 05/2014, A5E03981761-AC
S7-1500