ABB RET670 Product Manual page 58

Transformer protection RET670
Pre-configured
Product version: 1.1
Table 33. Four step phase overcurrent protection OC4PTOC
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 89, table 90 and
table 91
Operate time, start
function
Reset time, start function
Critical impulse time
Impulse margin time
58
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
25 ms typically at 2 to 0 x I
10 ms typically at 0 to 2 x I
15 ms typically
1MRK 504 091-BEN B
Issued: June 2010
Accuracy
± 1.0% of I at I £ I
r
± 1.0% of I at I > I
-
± 1.0% of I
r
± 2.0 degrees
± 2.0 degrees
± 2.0 degrees
± 2.0% of I
r
± 0.5% ± 10 ms
± 0.5% ± 10 ms
See table 89, table
table 91
-
set
-
set
-
set
-
r
r
90 and
ABB