Cal Over Current
Uploaded by
Insan AzizCal Over Current
Uploaded by
Insan AzizFORMULA
T = TDM x
K / ( ( I/Ipickup) E - 1 )
T
= Trip time ( sec )
TDM = TD Multiplier
I
= Input current
Ipickup = Pickup current setpoint
K,E = Constants
IEC ( BS ) INVERSE TIME CURVE CONSTANTS
CONSTANTS
IEC (BS) CURVE SHAPE
K
E
tr
IEC CURVE A ( BS 1 42 )
0.140
0.020
9.700
IEC CURVE B ( BS 1 42 )
13.500
1.000
43.200
IEC CURVE C ( BS 1 42 )
80.000
2.000
58.200
AUTOMATIC CALCULATION
CURVE
IEC CURVE A ( BS 1 42 )
IEC CURVE B ( BS 1 42 )
IEC CURVE C ( BS 1 42 )
TD
I fault ( Ipickup
Multiplier ?
A) ?
( A) ?
0.63
2.00
0.41
0.30
3.00
1.00
0.30
1.50
1.00
*Note : Voltage restraint disable = 1
Voltage
restraint
1.00
1.00
1.00
Trip times ( s ) =
2.7172
2.0159
19.2000
FORMULA
T = TDM A + B/(I/Ipickup - C) + D/(I/Ipickup - C)2 + E/(I/Ipickup - C)3
T
= Trip time ( sec )
TDM = TD Multiplier
I
= Input current
Ipickup
= Pickup current setpoint
A,B,C,D,E = Constants
GE IAC INVERSE TIME CURVE CONSTANTS
IAC CURVE SHAPE
IAC EXTREME INVERSE
IAC VERY INVERSE
IAC INVERSE
IAC SHORT INVERSE
A
0.0040
0.0090
0.2078
0.0428
B
0.6379
0.7955
0.8630
0.0609
CONSTANTS
C
0.6200
0.1000
0.8000
0.6200
D
1.7872
-1.2885
-0.4180
-0.0010
E
0.2461
7.9586
0.1947
0.0221
AUTOMATIC CALCULATION
CURVE
IAC EXTREME INVERSE
IAC VERY INVERSE
IAC INVERSE
IAC SHORT INVERSE
TD
I fault ( Ipickup
Multiplier ?
A) ?
( A) ?
5.00
5.00
4.00
5.00
6.00
4.00
5.00
2.00
1.00
0.00
0.00
1.00
*Note : Voltage restraint disable = 1
Voltage
Restraint
1.00
1.00
1.00
1.00
Trip times ( s )
32.5183
14.1009
3.7468
0.0000
FORMULA
T = TDM A + B/(I/Ipickup - C) + D/(I/Ipickup - C)2 + E/(I/Ipickup - C)3
T
= Trip time ( sec )
TDM = TD Multiplier
I
= Input current
Ipickup
= Pickup current setpoint
A,B,C,D,E = Constants
ANSI INVERSE TIME CURVE CONSTANTS
ANSI CURVE SHAPE
EXTREME INVERSE
VERY INVERSE
NORMALLY INVERSE
MODERATELY INVERSE
A
0.0399
0.0615
0.0274
0.1735
B
0.2294
0.7989
2.2614
0.6791
CONSTANTS
C
0.5000
0.3400
0.3000
0.8000
D
3.0094
-0.2840
-4.1899
-0.0800
E
0.7222
4.0505
9.1272
0.1271
AUTOMATIC CALCULATION
CURVE
EXTREME INVERSE
VERY INVERSE
NORMALLY INVERSE
MODERATELY INVERSE
TD
I fault ( Ipickup
Multiplier ?
A) ?
( A) ?
4.00
4.00
2.00
0.00
0.00
1.00
5.00
10.50
3.00
0.00
0.00
1.00
*Note : Voltage restraint disable = 1
Voltage
Restraint
1.00
1.00
1.00
1.00
Trip times ( s )
6.9773
0.0000
3.0173
0.0000
FORMULA
T = TDM x
( A / ( ( I/Ipickup) p - 1 ) ) + B
T
= Trip time ( sec )
TDM = TD Multiplier
I
= Input current
Ipickup = Pickup current setpoint
A, B, p = Constants
IEEE INVERSE TIME CURVE CONSTANTS
IEEE CURVE SHAPE
IEEE Extremely Inverse
IEEE Very Inverse
IEEE Moderately Inverse
A
28.200
19.610
0.052
CONSTANTS
B
p
0.1217
2.0000
0.4910
2.0000
0.1140
0.0200
tr
29.100
21.600
4.850
AUTOMATIC CALCULATION
CURVE
IEEE Extremely Inverse
IEEE Very Inverse
IEEE Moderately Inverse
TD
I fault ( Ipickup
Multiplier ?
A) ?
( A) ?
4.00
10.00
2.00
0.00
0.00
1.00
0.00
0.00
1.00
*Note : Voltage restraint disable = 1
Voltage
restraint
1.00
1.00
1.00
Trip times ( s ) =
5.1868
0.0000
0.0000
FORMULA
T = TDM x
100 / ( ( I/Ipickup) 2 )
T
=
TDM =
I
=
Ipickup
Trip time ( sec )
TD Multiplier
Input current
= Pickup current setpoint
AUTOMATIC CALCULATION
TD
I fault ? Ipickup ?
Multiplier ?
( A)
( A)
0.01
2.00
1.00
*Note : Voltage restraint disable = 1
Voltage
restraint
1.00
Trip times ( s ) =
0.2500