User Manual

Retention
283
08/04 AWB2528-1423GB
Retention It is a requirement of system and machine controllers for
operating states or actual values to have retentive settings.
What this means is that the values will be retained safely
even after the supply voltage to a machine or system has
been switched off and are also retained until the next time
the actual value is overwritten.
The following operands and function blocks can be set to
operate retentively:
•Markers
• Counter function blocks,
• Data function blocks and
• Timing relays.
Operating hours counter
easy800 provides four retentive operating hours counters.
They are always retentive and can only be selectively deleted
with a reset command.
Retentive data volume
200 bytes is the maximum memory range for retentive data
(operating hours counters are not included).
Markers
A user-definable and consistent marker range can be
declared as retentive.
Counters
All C.., CH.. and CI.. function blocks can be operated with
retentive actual values.
Data function blocks
A user-definable consistent data function block range can
be operated with retentive actual values.
Timing relays
A user-definable and consistent range for timing relays can
be run with retentive actual values.