ABB Relion 670 Series Applications Manual page 467

1MRK 505 370-UUS Rev. K
19.4 Denial of service SCHLCCH/RCHLCCH
19.4.1 Application
The denial of service functionality is designed to limit the CPU load that can be produced by Ethernet
network traffic on the IED. The communication facilities must not be allowed to compromise the primary
functionality of the device. All inbound network traffic will be quota controlled so that too heavy network
loads can be controlled. Heavy network load might for instance be the result of malfunctioning equipment
connected to the network.
The functions Access point diagnostics function block measure the IED load from communication and, if
necessary, limit it for not jeopardizing the IEDs control and protection functionality due to high CPU load.
The function has the following denial of service related outputs:
• LINKSTS indicates the Ethernet link status for the rear ports (single communication)
• CHALISTS and CHBLISTS indicates the Ethernet link status for the rear ports channel A and B
(redundant communication)
• LinkStatus indicates the Ethernet link status for the front port
19.4.2 Setting guidelines
The function does not have any parameters available in the local HMI or PCM600.
Busbar protection REB670
Application manual
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Section 19
Security
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GUID-CE3344E8-539B-47E0-9C19-8239988BDBCF v3
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