Multi-Tech Systems 7600 User Manual
ION 7500 / ION 7600 User’s Guide
Clock Module Settings
Time Synchronization & Timekeeping Technical Note
Page 349
Clock Module Settings
The Clock module controls an ION meter’s internal clock. In order to correctly set
up time synchronization with your single meter or network, you need to be
familiar with certain features of the Clock module. Essentially, you need to
configure the Clock module’s Setup registers to correspond to the type of time
synchronization you desire. You use Designer software or the front panel’s Setup
menu to configure the Clock module.
up time synchronization with your single meter or network, you need to be
familiar with certain features of the Clock module. Essentially, you need to
configure the Clock module’s Setup registers to correspond to the type of time
synchronization you desire. You use Designer software or the front panel’s Setup
menu to configure the Clock module.
Clock Source Used for Synchronization:
The Clock Source setup register has three settings from which to choose, depending
on the method of time synchronization. The ION 7500 / ION 7600 and ION 8000
Series of meters have all three settings available as options. The ION 7700 and ION
7300 Series only have the
on the method of time synchronization. The ION 7500 / ION 7600 and ION 8000
Series of meters have all three settings available as options. The ION 7700 and ION
7300 Series only have the
INTERNAL
setting.
LINE
FREQUENCY
:
When the Clock Source is set to monitor the ISO Grid Operation line frequency,
each meter auto-corrects the internal clock based on the measured line
frequency. Over a long period of time, this form of time keeping is highly
accurate. If a power outage occurs, the clock automatically synchronizes with
the meter’s internal crystal until power is restored. Once the power is restored,
the clock once again synchronizes with the line frequency. Meters synchronize
with the line frequency by default.
each meter auto-corrects the internal clock based on the measured line
frequency. Over a long period of time, this form of time keeping is highly
accurate. If a power outage occurs, the clock automatically synchronizes with
the meter’s internal crystal until power is restored. Once the power is restored,
the clock once again synchronizes with the line frequency. Meters synchronize
with the line frequency by default.
INTERNAL
:
If you prefer having the meter itself provide timekeeping, set the Clock Source
setup register to
setup register to
INTERNAL
. The clock then synchronizes to the meter’s internal
crystal.
COMM
:
Use this for the Clock Source if you set the Sync Source setup register (see below)
to a COM port to receive GPS time synchronization signals.
to a COM port to receive GPS time synchronization signals.
Type of Time Used for Synchronization:
The Time Sync Type setup register specifies whether time synchronization signals are
received in Coordinated Universal Time (UTC) or Local Time.
received in Coordinated Universal Time (UTC) or Local Time.
UTC
:
Coordinated Universal Time is the standard time common to every place in the
world. Formerly and still widely called Greenwich Mean Time (GMT), UTC
nominally reflects the mean solar time along the Earth's prime meridian. It is
expressed using a 24-hour clock but can be converted into a 12-hour clock (AM
and PM). The time kept on the ION meter is always UTC (24-hour clock). When
using UTC, the TZ Offset and DST Offset setup registers (see below) are not
required. The Time Sync Type setup register is set to
world. Formerly and still widely called Greenwich Mean Time (GMT), UTC
nominally reflects the mean solar time along the Earth's prime meridian. It is
expressed using a 24-hour clock but can be converted into a 12-hour clock (AM
and PM). The time kept on the ION meter is always UTC (24-hour clock). When
using UTC, the TZ Offset and DST Offset setup registers (see below) are not
required. The Time Sync Type setup register is set to
UTC
by default.
LOCAL
:
This setting requires that the time zone offset and DST offset are filled in
correctly. Thus, Local time is basically the UTC adjusted for time zone and
daylight savings time. There are some DNP masters and GPS receivers that use
Local time; for these only, change the Time Sync Type from its default
setting to
correctly. Thus, Local time is basically the UTC adjusted for time zone and
daylight savings time. There are some DNP masters and GPS receivers that use
Local time; for these only, change the Time Sync Type from its default
setting to
LOCAL
.