Retentivity; Parameter Protection - Siemens Logo! Manual

LOGO! functions
S
Equipment series 0BA0:
On restarting, the clock is set to "Sunday 00:00 1 Ja-
nuary". The time starts to run. Due to this, the system
processes the time switches, which trigger actions, if
necessary.
S
Equipment series 0BA1 and later:
On restarting, the clock is set to "Sunday 00:00 1 Ja-
nuary". The time is stopped and flashes. LOGO! is back
in the status that it was in before the power outage.
In the RUN status, the system processes the counters
that were parameterized with the time above. The clock
is, however, still stopped.

4.3.4 Retentivity

The switching states and counter values of SFs can be set
retentive. This means that current data are retained after a
power failure, and that the block resumes operation at the
break point. The timer is not reset, but resumes operation
until the time-to-go has expired, for example.
To enable this response, however, the relevant functions
must be set retentive. Two options are available:
R: The data is retained.
/: Current data is not retained (default). See the example on
Page 91.
The hours counter is an exception because this function is
always retentive.

4.3.5 Parameter protection

In the parameter protection settings, you can determine
whether the parameters can be displayed and edited in
LOGO! parameter assignment mode or not. Two options
are available:
+: The parameter attribute permits read/write access in pa-
rameter assignment mode (default).
–: The parameter settings are read-/write-protected in
parameter assignment mode, and can be edited only in
programming mode. See the example on Page 91.
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LOGO! Manual
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