ABB REL670 2.2 IEC, Applications Manual

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25.4 PTP requirements
GUID-741CC863-D760-49D6-85B2-AFECA222A8C3 v1
For PTP to perform properly, the Ethernet equipment that is used needs to be
compliant with IEEE1588. The clocks used must follow the IEEE1588 standard
BMC (Best Master Algorithm) and shall, for instance, not claim class 7 for a longer
time than it can guarantee 1us absolute accuracy.
25.5 Sample specification of communication
requirements for the protection and control
terminals in digital telecommunication networks
GUID-0A9F36AF-3802-42FE-8970-4662798C19D1 v3
The communication requirements are based on echo timing.
Bit Error Rate (BER) according to ITU-T G.821, G.826 and G.828
•
<10
-6
according to the standard for data and voice transfer
Bit Error Rate (BER) for high availability of the differential protection
•
<10
-8
-10
-9
during normal operation
•
<10
-6
during disturbed operation
During disturbed conditions, the trip security function can cope with high bit error
rates up to 10
-5
or even up to 10
-4
. The trip security can be configured to be
independent of COMFAIL from 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
1MRK 506 369-UEN B
Section 25
Requirements
Line distance protection REL670 2.2 IEC 887
Application manual