Mitsubishi Electric MELSEC-Q Series User Manual page 107

7 FUNCTION
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(3) Precautions
(a) The clock data is not set before shipment.
The clock data is used by the Basic model QCPU system and intelligent
function module for failure history and other functions. Be sure to set the
accurate time when operating the Basic model QCPU for the first time.
(b) Even if a part of the time data is being corrected, all data must be written to
the clock again.
(c) The data written in the clock element is checked in the range described in
(1) (b) of Section 7.5.
For this reason, if improbable clock data in the range described in (1) (b) of
Section 7.5 is written in the clock element, correct clock function is
unavailable.
Example
Writing to clock element
February 30
32 of month 13 Not executed
(4) Precision
The precision of the clock function differs with the ambient temperature, as
shown below:
Ambient Temperature (
0
+25
+55
(5) Comparison of Clock Data
To compare Basic model QCPU's clock data with a sequence program, use the
DATERD instruction to read the clock data. The year data is read out in 4 digits.
It can be compared as it is by using a compare instruction.
Upon execution of DATEW command:
Executed
Upon activation of SM210:
)
C
MELSEC-Q
CPU module operation state
OPERATION ERROR (Error code 4100)
Activation of SM211
Failure to detect error
Accuracy (Day difference, S)
-3.2 to +5.27 (TYP.+1.98)
-2.57 to +5.27 (TYP.+2.22)
-11.68 to +3.65 (TYP.-2.64)
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