ABB RELION 670 Series Technical Manual page 535

1MRK 502 066-UUS B
When one of the two "follow modes" is used, there is a settable timer
block the external INITIATE input signal when it times-out. This will automatically also reset the
t2 timers and consequently prevent any backup trip command. At the same time the STALARM
and
output from the function will have logical value one. To reset this signal external INITIATE signal
shall be removed. This is done in order to prevent unwanted operation of the breaker failure
function for cases where a permanent INITIATE 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
timer.
The BLOCK signal overrides any
t2 timers and all function outputs.
PICKUP
Current Check
CB Position Check
ANSI18001002 V1 EN-US
Figure 275: Simplified overall logic for LatchedStart
PICKUP
Current Check
CB Position Check
ANSI18001003 V1 EN-US
Figure 276: Simplified overall logic for FollowStart
Technical manual
StartMode condition and resets INITIATE signal, running of t1 and
30ms t1
S Q
t
R
t2
t
150ms
t
t1 t1
OR OR
t t
OR
t2 t2
t t
OR OR
tStartTimeout which will
30ms
OR
AND
30ms
OR
AND
OR
AND
NOT
ANSI 18001002-1-en.vsdx
TRRET
AND
TRBU
AND
ANSI18001003-1-en.vsdx
Section 8
Current protection
t1
tStartTimeout
TRRET
TRBU
529