Operation Principle - ABB Relion 650 Series Technical Manual

1MRK 511 424-UEN B
15.1.3
15.1.3.1
Bay control REC650 2.2 IEC
Technical manual

Operation principle

General concepts
Time definitions
The error of a clock is the difference between the actual time of the clock, and the
time the clock is intended to have. Clock accuracy indicates the increase in error,
that is, the time gained or lost by the clock. A disciplined clock knows its own
faults and tries to compensate for them.
Design of the time system (clock synchronization)
The time system is based on software and hardware clocks that run independently
from each other (see Figure 276).
External
synchronization
sources
Off
LON
SPA
Min. pulse
SNTP
DNP
IRIG-B
PPS
Off
IRIG-B
PPS
IEC16000002 V2 EN-US
Figure 276: Design of the time system (clock synchronization)
All time tagging is performed by the software clock. When, for example, a status
signal is changed in the protection system of a function based on the free running
hardware clock, the event is time tagged by the software clock when it reaches the
event recorder. The hardware clock can thus run independently.
PTP(IEEE 1588)
Off
On
Time tagging and general synchronization
Slave only
Commu-
nication
Time
regulator
(Setting:
SW time
see
Technical
manual)
Time
HW time
regulator
(fast or slow)
converter
Section 15
Basic IED functions
GUID-E2B9E81C-5733-4521-B27F-BF33E05CCFB0 v10
Protection
Events
and control
functions
Synchronization for differential protection
(Echo mode)
Diff.
A/D
commu-
nication
*IEC 61850-9-2
IEC16000002-2-en.vsdx
IP12360-1 v4
M11346-77 v1
M11346-80 v3
Merging
units*
617