Time Zone Offsets; Daylight Saving Time - Symmetricom ND-CLK User Manual

Time Zone Offsets

All network clocks maintain time as UTC (UTC is sometimes equated with or referred to
as GMT) internally. A time zone offset (or bias) can be provided to adjust the time for
display purposes. A bias can be set as a positive (+) or negative (-) value with a
resolution of one second.
[Note: Factory default: Time Zone Offset configuration for displaying local time is
disabled. You must enable and configure the settings to display local time.]
[Note: It is highly suggested to utilize an NTP time server with UTC reference and
configuring the offsetting for your time zone and DST in your local time display clock.]

Daylight Saving Time

A daylight savings time (summer time) adjustment can be configured separately and in
addition to a time zone offset.
Network time displays provide flexible configuration options supporting most world
daylight time standards.
Daylight time standards vary widely throughout the world. Traditional daylight/summer
time is configured as one (1) hour positive bias. The new US/Canada DST standard,
adopted in the spring of 2007 is: one (1) hour positive bias, starting at 2:00am on the
second Sunday in March, and ending at 2:00am on the first Sunday in November. In the
European Union, daylight change times are defined relative to the UTC time of day
instead of local time of day (as in U.S.). European customers, please carefully consult
the section entitled Device Settings for details on setting daylight time.
To ensure proper hands-free year-around operation, the automatic daylight time
adjustments must be configured using the daylight time option and not with the time zone
offset option.
[Note: Factory default: Automatic daylight savings time is disabled. You must enable
and configure the settings to display local time with DST.]
ND-CLK User Manual- Rev 1.0.1 - Sep-08
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Symmetricom , Inc