ABB Relion 670 series, Technical Reference Manual

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4.14.3 Function block
IEC06000503-2-en.vsd
ATHSTAT
USRBLKED
LOGGEDON
IEC06000503 V2 EN
Figure 42: ATHSTAT function block
4.14.4 Output signals
Table 56: ATHSTAT Output signals
Name Type Description
USRBLKED BOOLEAN At least one user is blocked by invalid password
LOGGEDON BOOLEAN At least one user is logged on
4.14.5 Setting parameters
The function does not have any parameters available in the local HMI or PCM600.
4.15 Denial of service DOS
4.15.1 Introduction
The Denial of service functions (DOSFRNT, DOSOEMAB and DOSOEMCD) are
designed to limit overload on the IED produced by heavy Ethernet network traffic. 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.
4.15.2 Principle of operation
The Denial of service functions (DOSFRNT, DOSOEMAB and DOSOEMCD)
measures 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 outputs:
1MRK505222-UUS C
Section 4
Basic IED functions
117
Technical reference manual