ABB RELION REX640 - 4.3.8.9 Signals; MHZPDIF Input signals

I A A A A
prim
= ⋅ + ⋅ +
( )
≈1000 0 020 2 0 0085 0 37. .
(Equation 229)
The power of the stabilizing resistor is calculated as follows.
P
V
W≥
( )
≈
323
3900
27
2
Ω
(Equation 230)
The need for voltage dependent resistor is checked with equations
U
A
kV
max
. . . .=
⋅
⋅ + + +
( )
≈
12 770
1000
3900 15 3 1 73 0 10 36 2Ω Ω Ω Ω
(Equation 231)
˘
.u V V V kV= ⋅ ⋅ −
( )
≈2 2 323 36200 323 9 6
(Equation 232)
The voltage dependent resistor, one for each phase, is needed in this case because
the voltage during the fault is much higher than 2 kV.
The leakage current through the varistor at the stabilizing voltage can be available
from the varistor manual, assuming that to be approximately 2 mA at stabilizing
voltage.
Iu A≈ 0 002.
(Equation 233)
The sensitivity of the protection can be re-calculated taking into account the
leakage current through the varistor as per equation
I A A A A
prim
= ⋅ + ⋅ +
( )
≈1000 0 020 2 0 0085 0 002 39. . .
(Equation 234)
4.3.8.9 Signals
MHZPDIF Input signals
Table 727: MHZPDIF Input signals
Name
Type Default Description
I3P SIGNAL - Three-phase currents
BLOCK BOOLEAN 0=False Block signal for acti-
vating the blocking
mode
1MRS759142 F Protection functions
REX640
Technical Manual
817