Table of Contents
Advertisement
Functions
Z1B Overreach
Zone
130
Consequently, the secondary side setting value of zone 1 at address 3306 ZONE Z1
is:
Z1
=
secondary
Note: The following ratio would result from the connection of a 5 A device to a 5 A
transformer:
Z1
=
secondary
The following primary reactance results for a 100 % reach for zone 2:
100
--------- -
Z2
=
prim
100
The following secondary side setting value of zone 2 results at address 3310 ZONE
Z2:
Z2
=
secondary
t
T3
T2
T1
X
=0.70*X
1
X
=X
1
1Transf
G
Z<
Figure 2-62
Time Grading for Machine Impedance Protection – Example
The Z1B overreach zone (address 3308 ZONE Z1B) is an externally controlled stage
which does not influence the Z1 normal stage. Consequently, there is no changeover,
but the overreach zone is switched effective or ineffective, depending on the position
of the high-voltage side circuit breaker.
⁄
500 A 1 A
----------------------------------- - 0.3669 Ω
⋅
⁄
6.3 kV 100 V
⁄
500 A 5 A
----------------------------------- - 0.3669 Ω
⋅
⁄
6.3 kV 100 V
2
7
6.3
⋅
⋅
0.5242 Ω
--------- -
---------- -
=
100
5.3
⁄
500 A 1 A
----------------------------------- - 0.5242 Ω
⋅
⁄
6.3 kV 100 V
1Transf
Internal consumption
BI
2.91 Ω
=
0.58 Ω
=
4.16 Ω
=
Z1
Z1B
Z2
(X
,
(X
,
(X
,
1B
1
2
R
)
R
)
R
)
1B
1
2
C53000-G1176-C149-3
Z
7UM62 Manual
Advertisement
Table of Contents
