Time zone properties

On this page, you can set properties of the selected time zone. The following table explains the meanings of particular properties:

Display name	Display name of the time zone.
Code name	Code name of the time zone.
GMT difference	Difference in hours between the time zone and Greenwich Mean Time.
Use daylight saving time	If checked, the daylight saving (DST) time will be used for this time zone; values set in the DST start rule and DST end rule properties will be used to define the DST interval.
DST starts at	Based on values set in DST start rule, this field will display the exact time when the time advance will occur.
DST ends at	Based on values set in DST end rule, this field will display the exact time when the time advance will be rolled back.
DST start rule & DST end rule	Using these sets of properties, you can exactly define when should the time advance be carried out; the way it is done is described below.
Month	Month in that the time advance occurs.
Condition	Condition specifying the day on that the change occurs. Based on the selected option, you can select day of the week, day number or a combination of both. See examples below for further explanation.
Day	Two fields - day of the week and day number - can be used based on the selected Condition. See examples below for further explanation.
Time	Exact time of the time advance.
Value	Number of hours that will be added to the current time when the time advance occurs.

The following table explains the meanings of possible options for the Condition parameter:

FIRST	Day of the week can be selected. If you select Monday, the time advance will occur on the first Monday of the selected month.
LAST	Day of the week can be selected. If you select Monday, the time advance will occur on the last Monday of the selected month.
>=	Day of the week and day number can be selected. If you select Monday and 15, the time advance will occur on the first Monday after the 15th day of the selected month.
<=	Day of the week and day number can be selected. If you select Monday and 15, the time advance will occur on the last Monday before the 15th day of the selected month.
=	Day number can be selected. If you select 15, the time advance will occur on the 15th of the selected month.

Examples

If you want to set the start time of the DST to the last Sunday in March at 2:00 AM, you should use the following values:

Month - March

Condition - LAST

Day - Sunday

Time - 2:00

Value - 1

If you want to set the end time of the DST to the last Saturday before the 20th of October at 11:00 PM, you should use the following values:

Month - October

Condition - <=

Day - Saturday; 20

Time - 23:00

Value - 0