The merging unit can be set to determine the correct date for the DST shift every year. The UTC time is used to set the DST.
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Set the DST on day (weekday) and DST off day (weekday) parameters to define on which week day the time shift occurs.
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Set the DST on date (day), DST on date (month) and DST off date (month) parameters to define on which month and week the time shift occurs.
Table 1. Possible date values for DST change on Sunday
| Day of the DST shift |
DST on/off date (day) |
| First Sunday of the month |
1 |
| Second Sunday of the month |
8 |
| Third Sunday of the month |
15 |
| Fourth Sunday of the month |
22 |
| Last Sunday, if the month has 30 days |
24 |
| Last Sunday, if the month has 31 days |
25 |
The DST on/off date must precede the selected DST on/off day and be within the same week as the DST shift.
For example, if the DST is observed from the last Sunday in March to the last Sunday in October and the time shift occurs at 01:00 UTC, the setting parameters are the following.
| DST on time (hours): |
2 h |
| DST on time (minutes): |
0 min |
| DST on date (day): |
25 |
| DST on date (month): |
March |
| DST on day (weekday): |
Sunday |
| DST off time (hours): |
1 h |
| DST off time (minutes): |
0 min |
| DST off date (day): |
25 |
| DST off date (month): |
October |
| DST off day (weekday): |
Sunday |
Note: Set the DST on day (weekday) and DST off day (weekday) to "reserved" to determine the exact date and time for the DST shift. Repeat the setting yearly, as the time for the DST shift is not on the same date every year.
Note: To disable the DST, set the DST in use parameter to "False".