ABB KLF-1, Инструкция

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I.L. 41-748.1F
9
where
Z
base
= one per unit primary ohms/as seen
from the relay
kv = rated phase-to-phase voltage of
the machine.
kVA = rated kVA of the machine.
R
C
= the current transformer ratio.
R
V
= the potential transformer ratio.
The actual settings, Z
A
and Z
C
are:
Z
A
= )Z
A
per unit) x (Z
base
)
Z
C
= (Z
C
per unit) x (Z
base
) =
(2
R
-Z
A
) x (Z
base
)
where R = radius of circle in per unit.
The tap-plate settings are made according to equa-
tions:
(5)
where:
T = compensator tap value
S = auto-transformer primary tap value
M = auto-transformer secondary tap value
(M is a per-unit value determined by taking the sum
of the values between the L and R leads. The sign is
positive when L is above R and acts to lower the Z
setting. The sign is negative when R is above L and
acts to raise the Z setting).
The following procedure should be followed to obtain
an optimum setting of the relay:
1. Select the lowest tap S which give a product
of 18.6S
A
greater than desired Z
A
and a
product of 6S
C
greater than desired Z
C
.
Z
base
1000
kv
( )
2
R
C
kva
( )
R
V
----------------------------------- ohms
=
Z
A
or Z
C
( )
TS
1 M
±
-------------- =
Figure 9. Diagram of Test Connections for KLF-1 Relay
292B545