Daylight Saving Time Function - Mitsubishi Electric MELSEC iQ-R C R12CCPU-V User Manual

Daylight saving time function

The daylight saving time function adjusts the time of a C Controller module to daylight saving time.
This function advances the time of a C Controller module by one hour on the start date and time, and reverses it by one hour
on the end date and time.
• When daylight saving time starts at 2:00 on the second Sunday in March (1), and ends at 2:00 on the first Sunday in
November (2)
(1)
A
01:59:59
B
01:59:59
A: Before adjustment
B: After adjustment
C: Daylight saving time
Before using daylight saving time, check the version of a C Controller module and an engineering tool.
(Page 253 Added and Changed Functions)
Timing of daylight saving time adjustment
Daylight saving time is adjusted at the following timing:
• At the start and end of daylight saving time
• Turn the power OFF and ON, or reset the C Controller module
Operation check of the daylight saving time function
The operation of the daylight saving time function can be checked by the following:
■C Controller module dedicated function
Whether the date lies inside or outside the daylight saving time period can be checked by using the C Controller module
dedicated function (CCPU_GetRTC).
■Event history
The history for the start and end of daylight saving time can be checked in the event history for the date set in the daylight
saving time setting.
Operation of other functions using clock data
The following table shows the operation of the functions using clock data in a C Controller module during the daylight saving
time period.
Item
Clock data reading
Clock data writing
4 BASIC FUNCTIONS
36
4.2 Clock Function
02:00:00 02:00:01
03:00:00 03:00:01
Description
Read clock data after adjusting the time for daylight saving time.
Write as clock data after adjusting the time for daylight saving time.
(2)
00:59:59 01:00:00
01:59:59 01:00:00
C
01:00:01
01:00:01