ABB RELION 650 SERIES, Руководство по применению

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R
CT
The secondary resistance of the CT ( W )
R
L
The resistance of the secondary cable and additional load ( W ). The loop
resistance containing the phase and neutral wires, must be used for faults
in solidly grounded systems. The resistance of a single secondary wire
should be used for faults in high impedance grounded systems.
S
R
The burden of an IED current input channel (VA). S
R
=0.010 VA/channel for
I
r
=1 A and S
R
=0.250 VA/channel for I
r
=5 A
Independent of the value of I
op
the maximum required E
al
is specified according to the following:
s n R
a l a lre q ma x CT L
2
pn n
k ma x
I S
E E I R R
I I
³ = × + +
æ ö
×
ç ÷
è ø
EQUATION1680 V1 EN-US
(Equation 35)
where
I
kmax
Maximum primary fundamental frequency current for close-in faults (A)
16.1.6.5 Directional phase and residual overcurrent protection
M11624-3 v5
If the directional overcurrent function is used the CTs must have a rated equivalent secondary
e.m.f. E
al
that is larger than or equal to the required equivalent secondary e.m.f. E
alreq
below:
s n R
a l a lre q CT L
2
pn n
k ma x
I S
E E I R R
I I
³ = × + +
æ ö
×
ç ÷
è ø
EQUATION1681 V1 EN-US
(Equation 36)
where:
I
kmax
Maximum primary fundamental frequency current for close-in forward and reverse faults (A)
I
pn
The rated primary CT current (A)
I
sn
The rated secondary CT current (A)
I
n
The rated current of the protection IED (A)
R
CT
The secondary resistance of the CT (
W
)
R
L
The resistance of the secondary cable and additional load ( W ). The loop resistance containing the phase
and neutral wires, must be used for faults in solidly grounded systems. The resistance of a single
secondary wire should be used for faults in high impedance grounded systems.
S
R
The burden of an IED current input channel (VA). S
r
=0.010 VA/channel for I
r
=1 A and S
r
=0.250 VA/channel
for I
r
=5 A
Section 16 1MRK 505 287-UUS B
Requirements
244 Busbar protection REB650
Application manual
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