Value of setting CB
failure mode
Value of setting CB
failure trip mode
Start logic reset condition
• The residual current drops below
Current
value Res
setting and (at least) two pha-
ses are below
Current value
setting.
In addition, the function is immediately reset if:
•
Start latching mode
is set to "Level sensitive", and the START signal is
deactivated. The recommended setting value is "Rising edge".
• The BLOCK input is activated.
AND
TON
150.0 ms
CB failure mode ”Current”
CB failure mode ”Breaker
status”
POSCLOSE
CB failure trip mode
“1 out of 4"
I
0
>
From Level detector 2
I >
From Level detector 1
Set
Reset
Enable timer
BLOCK
AND
OR
Start latching mode
”Level sensitive”
AND
START
AND
OR
CB failure trip mode
“1 out of 3"
CB failure trip mode
“2 out of 4"
AND
OR
AND
AND
AND
OR
CB failure mode ”Both(AND)”
CB failure mode ”Both(OR)”
AND
OR
I >
From Level detector 1
AND
I
0
>
From Level detector 2
2 or 3 ph
1 ph
Figure 661: Start logic
Timer 1
Once activated, the timer runs until the set
Retrip time
value has elapsed. The time
characteristic is according to DT. When the operation timer has reached the value
set with
Retrip time
, the retrip logic is activated. A typical setting is 0...50 ms.
Timer 2
Once activated, the timer runs until the set
CB failure delay
value has elapsed. The
time characteristic is according to DT. When the operation timer has reached the set
maximum time value
CB failure delay
, the backup trip logic is activated. The value of
Protection related functions
1MRS759142 F
1166 REX640
Technical Manual
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