ANSI16000503-1-en.vsd
BFP Started A
AND
BFP Started B
BFP Started C
From other
phases
OR
OR
AND
AND
a
b
a>b
IN
IN>
1 out of 4
AND
OR
1 out of 3
Current High B
Current High C
From other
phases
AND
Current High A
OR
Contact Closed A
OR
Backup Trip A
200 ms
Backup Trip B
OR
From other
phases
Backup Trip C
TRBU
OR
2 out of 4
BUTripMode
1
AND
OR
Current High A
BFP Started A
30 ms
Backup Time Out A
AND
AND
AND
OR
OR
0
0-t2
0
60 s
ANSI16000503 V1 EN
Figure 56: Simplified logic scheme of the back-up trip function
Internal logical signals Current High A, Current High B, and Current High C have logical
value 1 when current in respective phase has magnitude larger than setting parameter
Pickup_PH.
6.7.8 Technical data
Table 72: CCRBRF (50BF) technical data
Function
Range or value Accuracy
Operate phase current (5-200)% of
lBase
± 1.0% of I
n
at I £ I
n
± 1.0% of I at I > I
n
Reset ratio, phase current > 95% -
Operate residual current (2-200)% of
lBase
± 1.0% of I
n
at I £ I
n
± 1.0% of I at I > I
n
Reset ratio, residual
current
> 95% -
Phase current pickup for
blocking of contact
function
(5-200)% of
lBase
± 1.0% of I
n
at I £ I
n
± 1.0% of I at I > I
n
Table continues on next page
1MRK 511 287-UUS A Section 6
Current protection
141
Technical manual