ABB RET670 Product Manual page 60

Transformer protection RET670
Pre-configured
Product version: 1.1
Table 35. Four step residual overcurrent protection EF4PTOC
Function
Operate current
Reset ratio
Operate current for
directional comparison
Timers
Inverse characteristics,
see table 89, table 90 and
table 91
Second harmonic restrain
operation
Relay characteristic angle
Minimum polarizing
voltage
Minimum polarizing
current
Real part of source Z
used for current
polarization
Imaginary part of source
Z used for current
polarization
Operate time, start
function
Reset time, start function
Critical impulse time
Impulse margin time
60
Range or value
(1-2500)% of lBase
> 95%
(1–100)% of lBase
(0.000-60.000) s
18 curve types
(5–100)% of fundamental
(-180 to 180) degrees
(1–100)% of UBase
(1-30)% of IBase
(0.50-1000.00) W/phase
(0.50–3000.00) W/phase
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
± 0.5% ± 10 ms
See table 89, table
table 91
± 2.0% of I
r
± 2.0 degrees
± 0.5% of U
r
±0.25% of I
r
-
-
-
set
-
set
-
set
-
r
r
90 and
ABB