ABB RED650 Technical Manual page 790

Section 21
Basic IED functions
784
Synchronization via binary input
The IED accepts minute pulses to a binary input. These minute pulses can be
generated from, for example station master clock. If the station master clock is not
synchronized from a world wide source, time will be a relative time valid for the
substation. Both positive and negative edge on the signal can be accepted. This
signal is also considered as a fine time synchronization signal.
The minute pulse is connected to any channel on any Binary Input Module in the
IED. The electrical characteristic is thereby the same as for any other binary input.
If the objective of synchronization is to achieve a relative time within the
substation and if no station master clock with minute pulse output is available, a
simple minute pulse generator can be designed and used for synchronization of the
IEDs. The minute pulse generator can be created using the logical elements and
timers available in the IED.
The definition of a minute pulse is that it occurs one minute after the last pulse. As
only the flanks are detected, the flank of the minute pulse shall occur one minute
after the last flank.
Binary minute pulses are checked with reference to frequency.
Pulse data:
• Period time (a) should be 60 seconds.
• Pulse length (b):
• Minimum pulse length should be >50 ms.
• Maximum pulse length is optional.
• Amplitude (c) - please refer to section
Deviations in the period time (a) larger than 50 ms will cause TSYNCERR.
b
c
IEC05000251 V1 EN-US
Figure 363: Binary minute pulses
The default time-out-time for a minute pulse is two minutes, and if no valid minute
pulse is received within two minutes a SYNCERR will be given.
"Binary input module
a
en05000251.vsd
Line differential protection RED650 2.2 IEC
1MRK 505 394-UEN A
M11346-42 v6
(BIM)".
Technical manual