ABB Relion 670 Series Applications Manual page 613

1MRK 511 401-UEN Rev. K
•
<10
Bit Error Rate (BER) for high availability of the differential protection
•
<10
•
<10
During disturbed conditions, the trip security function can cope with high bit error rates up to
-5
10 or even up to 10
the differential protection communication supervision, or blocked when COMFAIL is issued
after receive error >100ms. (Default).
Synchronization in SDH systems with G.703 E1 or IEEE C37.94
The G.703 E1, 2 Mbit shall be set according to ITU-T G.803, G.810-13
• One master clock for the actual network
• The actual port Synchronized to the SDH system clock at 2048 kbit
• Synchronization; bit synchronized, synchronized mapping
• Maximum clock deviation <±50 ppm nominal, <±100 ppm operational
• Jitter and Wander according to ITU-T G.823 and G.825
• Buffer memory <250 μs, <100 μs asymmetric difference
• Format.G 704 frame, structured etc.Format.
• No CRC-check
Synchronization in PDH systems connected to SDH systems
• Independent synchronization, asynchronous mapping
• The actual SDH port must be set to allow transmission of the master clock from the PDH-
system via the SDH-system in transparent mode.
• Maximum clock deviation <±50 ppm nominal, <±100 ppm operational
• Jitter and Wander according to ITU-T G.823 and G.825
• Buffer memory <100 μs
• Format: Transparent
• Maximum channel delay
• Loop time <40 ms continuous (2 x 20 ms)
IED with echo synchronization of differential clock (without GPS clock)
• Both channels must have the same route with maximum asymmetry of 0,2-0,5 ms,
depending on set sensitivity of the differential protection.
• A fixed asymmetry can be compensated (setting of asymmetric delay in built in HMI or the
parameter setting tool PST).
IED with GPS clock
• Independent of asymmetry.
25.6 IEC/UCA 61850-9-2LE Merging unit requirements
The merging units that supply the IED with measured values via the process bus must fulfill the
IEC/UCA 61850-9-2LE standard.
This part of the IEC 61850 is specifying "Communication Service Mapping (SCSM) – Sampled
values over ISO/IEC 8802", in other words – sampled data over Ethernet. The 9-2 part of the
IEC 61850 protocol uses also definitions from 7-2, "Basic communication structure for
substation and feeder equipment – Abstract communication service interface (ACSI)". The set
of functionality implemented in the IED (IEC/UCA 61850-9-2LE) is a subset of the IEC
61850-9-2. For example the IED covers the client part of the standard, not the server part.
Bay control REC670
Application manual
-6
according to the standard for data and voice transfer
-8 -9
-10 during normal operation
-6
during disturbed operation
-4
. The trip security can be configured to be independent of COMFAIL from
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Section 25
Requirements
SEMOD166590-11 v5
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