ABB ret650, Applications Manual

Page: 365 / 392

18.12.2.3 Process bus IEC/UCA 61850-9-2LE synchronization
GUID-6E384BDB-5598-4108-99B4-0B4A4E1828B2 v4
When process bus communication (IEC/UCA 61850-9-2LE protocol) is used, it is
essential that the merging units are synchronized with the hardware time of the IED
(see Technical manual, section
Design of the time system (clock synchronization ) ).
To achieve this, PTP, PPS or IRIG-B can be used depending of the facilities of the
merging unit.
If the merging unit supports PTP, use PTP. If PTP is used in the IED and the
merging unit cannot be synchronized from the IED, then use GPS-based clocks to
provide PTP synch as well as sync to the merging unit.
If synchronization of the IED and the merging unit is based on GPS, set the
parameter
LostSyncMode to BlockOnLostUTC in order to provide a block of
protection functions whenever the global common time is lost.
If PTP is not used, use the same synchronization method for the HwSyncSrc as the
merging unit provides. For instance, if the merging unit provides PPS as
synchronization, use PPS as
HwSyncSrc . If LDCM in GPS-mode is used, that is,
the hardware and software clocks are connected to each other, HwSyncSrc is not
used and other means to synchronize the merging unit to the IED is required. For
instance,
FineSyncSource is set to the same source that the merging unit uses.
1MRK 504 169-UEN A
Section 18
Basic IED functions
Transformer protection RET650 2.2 IEC 359
Application manual