Clock Buffering; Retentivity - Siemens LOGO! 24RC Manual

Note
Always specify a time T
T = 0.00 s the time T is not defined.
Accuracy of T
All electronic components have minute differences. This
can result in deviations in the set time (T). In LOGO! the
maximum deviation is 1 %.
Example:
In 1 hour (3600 seconds) the deviation is 1 % (i.e. 36 sec-
onds).
In 1 minute the deviation is therefore only 0.6 seconds.
Accuracy of the time switch
To make sure that this deviation doesn't result in the clock
in C variants running inaccurately, the time switch is regu-
larly compared with a high-precision time base and ad-
justed accordingly.
This results in a maximum time error of

4.3.3 Clock Buffering

The internal clock of a LOGO! module continues to run if
there is a power failure, i.e. it has a power buffer. The dura-
tion of the reserve power is affected by the ambient tem-
perature. At an ambient temperature of 25 C the typical
power buffer is 80 hours.

4.3.4 Retentivity

The switching states and counter values can be kept reten-
tively in the special functions. To do this, retentivity must be
switched on for the relevant function.
LOGO! Manual
A5E00067781 01
LOGO! Functions
0.10 s. For T = 0.05 s and
5s a day.
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