ABB RET670 Product Manual page 53

ABB
Transformer protection RET670 ANSI
Pre-configured
Product version: 1.2
Current protection
Table 27. Four step phase overcurrent protection OC4PTOC (51/67)
Function
Operate current
Reset ratio
Min. operating current
Relay characteristic angle (RCA)
Maximum forward angle
Minimum forward angle
2nd harmonic blocking
Independent time delay
Minimum operate time
Inverse characteristics, see
table 78, table 79 and table 80
Operate time, pickup function
Reset time, pickup function
Critical impulse time
Impulse margin time
Setting range
(1-2500)% of lBase
> 95%
(1-100)% of lBase
(-70.0– -50.0) degrees
(40.0–70.0) degrees
(75.0–90.0) degrees
(5–100)% of fundamental
(0.000-60.000) s
(0.000-60.000) s
19 curve types
25 ms typically at 0 to 2 x I
set
25 ms typically at 2 to 0 x I
set
10 ms typically at 0 to 2 x I
set
15 ms typically
1MRK 504 118-BUS A
Accuracy
± 1.0% of I at I ≤ I
n n
± 1.0% of I at I > I
n
-
± 1.0% of I at I ≤ I
n n
±1.0% of I at I > I
n
± 2.0 degrees
± 2.0 degrees
± 2.0 degrees
± 2.0% of I
n
± 0.5% ±10 ms
± 0.5% ±10 ms
See table 78, table 79 and table
80
-
-
-
-
53