ABB Relion 670 Series Applications Manual page 200

Section 7
Current protection
when the CB position criterion is used, is either to shortly activate BLOCK input or setting CCSRBRF to
blocked when the IED is in test mode.
By setting the StartMode, it is possible to select how t1 and t2 timers are run and consequently how
output commands are given from the function:
• Option 1 - LatchedStart: "By external start signal which is internally latched".
When function is once started by external BFI_3P signal, the timers t1 and t2 will always elapse and
then measurement criterion defined by parameter FunctionMode will be always checked in order to
verify if the appropriate command shall be given out from the function. Timers cannot be stopped by
removing the external BFI_3P signal. Function can be started again only when all of the following
three timers t1, t2, and fixed timer of 150ms in function internal design has expired and the
measurement criterion defined by parameter FunctionMode has deactivated,
that this option corresponds to the function behavior in previous versions of the 670 Series from
version 1.0 up to and including version 2.1
• Option 2 - FollowStart: "Follow the external start signal only".
The timers t1 and t2 will run while external BFI_3P signal is present. If they elapse then
measurement criterion defined by parameter FunctionMode will be checked in order to verify if the
appropriate command shall be given out from the function. Timers can be always stopped by
resetting the external BFI_3P signal, see
• Option 3 - FollowStart&Mode: "Follow external start signal and selected FunctionMode".
The timers t1 and t2 will run while external BFI_3P signal is present and in the same time the
measurement criterion defined by parameter FunctionMode is active. If they elapse then the
appropriate command will be given out from the function. Timers can be stopped by resetting the
external BFI_3P signal or if the measurement criterion de-activates, see
When one of the two "follow modes" is used, there is a settable timer tStartTimeout which will block the
external BFI_3P input signal when it times-out. This will automatically also reset the t1 and t2 timers and
consequently prevent any backup trip command. At the same time the STALARM output from the
function will have logical value one. To reset this signal external BFI_3P signal shall be removed. This is
done in order to prevent unwanted operation of the breaker failure function for cases where a permanent
BFI_3P signal is given by mistake (e.g. due to a fault in the station battery system). Note that any backup
trip command will inhibit running of tStartTimeout timer.
PICKUP
Current Check
CB Position Check
ANSI18001002 V1 EN-US
Figure 105: Simplified overall logic for LatchedStart
194
30ms t1
S Q
t
R
t2
t
150ms
t
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Figure 106.
30ms
OR
AND
30ms
OR
AND
OR
AND
NOT
1MRK 505 370-UUS Rev. K
seeFigure 105. Note
Figure 107.
TRRET
TRBU
ANSI 18001002-1-en.vsdx
Busbar protection REB670
Application manual