ABB RET670 Product Manual page 78

Transformer protection RET670 ANSI
Pre-configured
Product version: 1.2
Table 79. IEC Inverse time characteristics
Function
Operating characteristic:
æ ö
A
ç ÷
= ×
t td
( )
ç ÷
P
è - ø
I 1
EQUATION1653 V1 EN
I = I /I
measured set
Time delay to reset, IEC inverse time
IEC Normal Inverse
IEC Very inverse
IEC Inverse
IEC Extremely inverse
IEC Short time inverse
IEC Long time inverse
Programmable characteristic
Operate characteristic:
æ ö
A
ç ÷
= + ×
t B td
( )
ç ÷
P
è - ø
I C
EQUATION1654 V1 EN
Reset characteristic:
TR
= ×
t td
( )
PR
-
I CR
EQUATION1655 V1 EN
I = I /I
measured set
78
Range or value
td = (0.05-999) in steps of 0.01
(0.000-60.000) s
A=0.14, P=0.02
A=13.5, P=1.0
A=0.14, P=0.02
A=80.0, P=2.0
A=0.05, P=0.04
A=120, P=1.0
td = (0.05-999) in steps of 0.01
A=(0.005-200.000) in steps of 0.001
B=(0.00-20.00) in steps of 0.01
C=(0.1-10.0) in steps of 0.1
P=(0.005-3.000) in steps of 0.001
TR=(0.005-100.000) in steps of 0.001
CR=(0.1-10.0) in steps of 0.1
PR=(0.005-3.000) in steps of 0.001
1MRK 504 118-BUS A
Accuracy
-
± 0.5% of set time ± 10 ms
IEC 60255-3, class 5 +
40 ms
IEC 60255, class 5 + 40
ms
ABB