Frequently Asked Questions
IntroductionIn many locations around the world, Daylight Saving Time is observed. Two times a year, special consideration needs to be taken into account to handle Daylight Saving Time. In the Spring, we "spring forward", meaning you set your clock ahead, effectively skipping an hour. In the Fall, we "fall back", meaning you set your clock back one hour, effectively gaining/repeating an hour). The dates and times this occurs depends on the year and your location. A good source for the dates and times of various locations are available on http://www.worldtimezone.com/daylight.html. As of 2007, in the USA (except Arizona and Hawaii) Daylight Saving Time begins at 2:00 AM on the 2nd Sunday of March and runs until the first Sunday of November at 2:00 AM. During these change-over periods you will need to take the time change into account when creating your program logs in Simian.
Simian Program LogUsing the following methods, you can program your logs in Simian to proceed through the change-over periods efficiently and effortlessly.
"Spring-forward"NOTE: As of 2007 in the US, the change over date has been changed to the second Sunday in March (instead of the last Sunday in April). During this change-over time, you will need to eliminate an hour from your log effectively making your log 23 hours. This means that your program log in Simian should proceed as normal, but should skip from 1:59:59 to 3:00:00, effectively skipping the 2:00 AM hour (see Figure 1 for example). There is no need to be concerned with timed events as you do with the "Fall-back" change-over because the 2:00 AM hour simply doesn't occur.
Figure 1: A program log is shown which skips the 2:00 AM hour (highlighted in orange) to take the "Spring-forward" Daylight Saving Time change-over into account.
"Fall-back"NOTE: As of 2007 in the US, the change over date has been changed to the first Sunday in November (instead of the last Sunday in October).
During this change-over time, you will need to add an extra hour to your day. There are two common methods of dealing with this, the method you should use depends on your situation.
The simple method can be used if you do not use timed events in the 1:00:00 to 2:00:00 hours. Simply double the 1:00 AM hour for a program log that lasts 25 hours; program your 1:00:00 hour with all AutoStart cued events, then create a second 1:00:00 hour worth of programming directly after the first 1:00 AM hour with all AutoStart events (see Figure 2 for example). The reason timed events can't be used with this method is the Program log will move to the last timed event for the particular time (IE: if you've got a timed event for 1:05:00 in both hours, the program log will move to the one in the second hour, skipping the rest of the first hour putting your log into the wrong position).
Figure 2: A simple program log is shown which adds an additional 1:00 AM hour (highlighted in orange) to take the "Fall-back" Daylight Saving Time change-over into account
The advanced method can be used if you require timed events in your 1:00 AM hour(s). This method uses 2 separate program logs for the change-over day. The first log covers your content from 00:00:00 through 1:59:59 (through to the end of the first 1:00 AM hour) , and the second log covers the content from 1:00:00 (the start of the second 1:00 AM hour) through the rest of the day. The key part of this method is the use of the CHAIN macro as the last event in the first log as a time immediate event at 1:59:59. This causes Simian to roll the first program log over at the end of the first 1:00 AM hour to the start of the second program log. The second program log starts at 1:00:00 which creates the second 1:00 AM hour worth of content (see Figure 3 and Figure 4).
Figure 3: A program log is shown which ends at 1:59:59 AM and rolls-over into a second program log with a CHAIN macro (highlighted in orange) to take the "Fall-back" Daylight Saving Time change-over into account.
Figure 4: A program log is shown which starts at 1:00 AM (highlighted in orange). This is the second log which is rolled-over from the log shown in Figure 3 by a CHAIN macro to take the "Fall-back" Daylight Saving Time change-over into account.
Simian Scheduled EventsSimian's Scheduled Events will simply skip over the 2:00 AM hour for the "Spring-forward" change-over, and will repeat your events in the 1:00 AM hour for the "Fall-back" hour without any user intervention what-so-ever.
Your ComputerIn addition to making sure your program logs in Simian take the time-change into account, you need to make sure your computer is properly configured.
Enabling Daylight Saving TimeWith Windows XP will automatically adjust the system clock when the "Automatically adjust clock for daylight saving changes" option is enabled (as shown in Figure 5). To enable this setting:
- Double-click on the system clock on the left corner of the Task Bar (or, in the Control Panel, double click on the "Date & Time" icon).
- In the window that pops-up, go to the Time Zone tab.
- Ensure the proper time zone is chosen (this is what determines what change-over date and time will be used).
- Enable the option for "Automatically adjust clock for daylight saving changes" in the lower right corner (see Figure 5)
- Click OK
Figure 5: The Time Zone tab of the Date and Time window are shown
Making sure your OS has the proper change-over datesLaws regarding the Daylight Saving Time change-over dates can change over time. To make sure your computer is properly updated with the most recent change-over dates, browse to the following Microsoft website:
NOTE: Microsoft does not offer updates for the Windows OS versions previous to Windows 2000 SP4 (such as Windows 95, 98, ME, etc.) and older versions of Windows may not change-over on the proper date.