ABB RELION RER670, Applications Manual

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The protection IED has effective filters for these transients, which gives secure and
correct operation with CVTs.
22.3 SNTP server requirements
GUID-588FCD12-C494-445E-8488-8287B34EFD9A v4
The SNTP server to be used is connected to the local network, that is not more than
4-5 switches or routers away from the IED. The SNTP server is dedicated for its
task, or at least equipped with a real-time operating system, that is not a PC with
SNTP server software. The SNTP server should be stable, that is, either
synchronized from a stable source like GPS, or local without synchronization.
Using a local SNTP server without synchronization as primary or secondary server
in a redundant configuration is not recommended.
22.4 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.
22.5 Sample specification of communication
requirements for the protection and control
terminals in digital telecommunication networks
GUID-0A9F36AF-3802-42FE-8970-4662798C19D1 v2
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
1MRK 506 375-UEN A
Section 22
Requirements
Railway application RER670 2.2 IEC 485
Application manual