Communications Ports and Protocols Used
Time synchronization signals from WinPM or a GPS receiver are received
through the communications ports on the 9700 Power Meter base unit and
optional XPRESS CARD. Signals can be received on the device’s COM 1 RS-
232/RS-485 port, the XPRESS CARD’S COM 2 or COM 3 RS-485 ports, or the
XPRESS CARD’S 10BaseT and 10BaseFL Ethernet ports.
An XPRESS CARD is required if time synchronization from a GPS receiver is
implemented (two communications ports are required in this configuration),
and COM1 should be used to receive time synchronization signals.
Time synchronization can be achieved using SEAbus and DNP3.0 protocols
(note that DNP 3.0 can be used on only one XPRESS CARD port per device).
GPS time synchronization uses special protocols defined for the type of GPS
receiver you are using.
Configuring the 9700 Power Meter to Interpret Time Synchronization
Signals
To implement GPS time synchronization, use WinPM or the MGT to
configure the Clock module and the Communications or Ethernet module:
♦ Specify which port will receive time synchronization signals by setting
the Time Sync Source setup register in the 9700 Power Meter’s Clock
module. Only signals received on the port specified will be used for
synchronization.
♦ Specify the protocol you want to use by setting the Protocol setup
register in the 9700 Power Meter’s Communications module (or Ethernet
module) for the port that receives the signals.
You may need to modify the “Time Sync Type” setup register if a DNP
Master is sending time broadcasts in local time.
If you are using WinPM as the source for time synchr onization signals, set
the Communications or Ethernet module’s Protocol setup register to
SEAbus. If you are using a GPS receiver as the time source, specify the
receiver type in the Protocol setup register that matches your receiver.
Various GPS receivers are supported by the 9700 Power Meter.
238)
Time synchronization
accuracy cannot be
guaranteed on Ethernet
networks.