6
FUNCTIONS
6.5 Clock Function
(1) Definition of Clock Function
(2) Clock operation at power OFF and momentary power failure
(3) Clock Data
6
6.5 Clock Function
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The clock function reads the internal clock data of the CPU module to use it for time
management.
The clock data is used by the CPU module system to perform time management, e.g.
storage of date into the error history.
Clock operation is continued by the internal battery of the CPU module during power
OFF of the PLC or when a power failure longer than the permissible momentary
power failure time occurs.
Clock data is used in the CPU module and includes the data indicated in Table6.4.
Data Name
Year
Month
Day
Hour
Minute
Second
Day of the week
Table6.4 Clock data details
Contents
Four digits in AD (Countable from 1980 to 2079)
1 to 31(Automatic leap year calculation)
0 to 23 (24 hours)
0
1
2
3
4
5
6
1 to 12
0 to 59
0 to 59
Sunday
Monday
Tuesday
Wednesday
Thursday
Friday
Saturday