Novatech Bitronics M87X Series, Manual

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ML0021 August 15, 2018
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Copyright 2018 Bitronics, LLC
and Requested DNP are ignored.
It should be noted that the IED host is not able to distinguish between the Modulated and
Unmodulated IRIG-B signals applied to the input port. Demodulation is accomplished by a
dedicated circuit. The host processor makes no determination as to which type of external
IRIG-B signal is applied. Unmodulated IRIG-B would provide a slightly more accurate time
signal then Modulated IRIG-B, due to additional time latency that is introduced in the de-
modulation process.
5.8.5 (UCA) Network Time Synchronization - time synchronization over Ethernet
The M87x real-time clock may be synchronized to a UCA network time-sync master. The
network time sync functions as described in IEEE TR-1550 Part 2 Appendix B and is
roughly analogous to the IRIG-B described in Section 5.6, in that the M87x continually
“trains” it’s internal clock to eliminate errors. An algorithm progressively adjusts the on-
board clock to improve its accuracy with subsequent time updates received from the
master. This allows the M87x to “Free Wheel” accurately in the event the UCA network
time-sync master is unavailable.
5.8.6 SNTP (Simple Network Time Protocol) - time synchronization over Ethernet
Time synchronization is supported using SNTP (Simple Network Time Protocol); this
protocol is used to synchronize the internal real time clock in substation devices , (i.e.,
control systems, relays, IEDs). Up to 2 SNTP servers, using optional many-cast (or any-
cast) mode of operation, are supported, along with configurable polling times. SNTP
servers can be polled for configurable time, but only one at a time.
The SNTP page in 70 the Series Configurator software tool allows the user the option of
selecting which tool will be used to load the SNTP (and IP) settings. Radio buttons are
provided for that purpose. SNTP (and IP) settings can be loaded from either the 70Series
Configurator (INI file) or the IEC61850 IED Configurator (MCL file). When using the
70Series Configurator, the initial default configuration will load SNTP settings from the
70Series Configurator (INI file). If IEC61850 protocol is used, it is possible for the user to
change the radio button selected in order to indicate that the IEC61850 IED Configurator
(MCL file) be used to load these settings instead. If the settings on the 70Series
Configurator SNTP page grey out, it is an indication that the SNTP server addresses may
have been set through the other Configurator’s software.
Additionally on the SNTP page of the 70 Series Configurator software, the user may
specify that an offset from the SNTP server time be applied when synchronizing. A
common use for this feature is to allow the 70 Series device to operate in local time when
synchronizing with an SNTP server operating in UTC time. To further support local
time, the application of Daylight Savings adjustments may also be configured.
5.8.7 DNP Time sync (slave requesting DNP time be set)
A slave may request thatDNP time be set in order to have the DNP master set the DNP
time.