Design - ABB REC 561 User Manual

1MRK 580 169-XEN
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3 Design

FUSE-MCB
FUSE-DISC
UICH
Operation=
Zeroseg
VTF0
Operation=
NegativeSeq
VTF2
UCHL1
UCHL2
UCHL3
VTF3PH-memory
Fuse-failure supervision function
50ms
t
200ms
t
&
&
25ms
1 &
t
25ms
&
t
&
20ms
Fig. 1
Figure 1 presents a simplified block diagram for the fuse failure supervi-
sion (FFS) function. The external signals perform their function even
when the function is switched off. The external signals are supposed to be
connected via the binary inputs of the terminal to the auxiliary contacts of
the line disconnector (FUSE-DISC) and miniature circuit breaker (FUSE-
MCB). Also, they can always operate in parallel with the zero-sequence
or negative-sequence measuring function.
An additional timer prolongs the presence of the FUSE-MCB signal for
50 ms to prevent the unnecessary operation of voltage-dependent func-
tions due to non-simultaneous closing of the main contacts on the minia-
ture circuit breaker.
50ms
t
&
5s
1
t
1
Fuse failure supervision function - simplified block diagram
ABB Network Partner AB
1
FUSE-VTSU
1
FUSE-VTSZ
50ms
t
1
FUSE-VTF3PH
Version 1.0-00
(X80169-1)