ABB RELION REX640 Technical Manual page 783

1MRS759142 F
P ≥
Based on
checked.
U
max
u ˘
= ⋅
The voltage-dependent resistor (one for each phase) is needed in this case as the
voltage during the fault is higher than 2 kV.
The leakage current through the VDR at the stabilizing voltage can be available from
the VDR manual, assuming that to be approximately 2 mA at stabilizing voltage
Iu ≈ 0 002
The sensitivity of the protection can be recalculated taking into account the leakage
current through the VDR as per
I
prim
4.3.6.8 Signals
HIAPDIF Input signals
Table 697: HIAPDIF Input signals
Name
I3P
BLOCK
REX640
Technical Manual
2
( 436 V )
≈ 32 W
5900 Ω
Equation 197
and
25000 A
= ( 5900 Ω + 15 75
2000
V V
2 2 436 ( 74000 436
⋅ ⋅ −
. A
2000 0 035 ( . 10 0 0034
A
= ⋅ + ⋅
Type
SIGNAL
BOOLEAN
Equation 198
, the need for voltage-dependent resistor is
kV
. Ω + 1 00 . Ω ) ≈ 74 0 .
V kV
) 16 0 .
≈
Equation 200
.
. 0 002 . ) 142
A A A
+ ≈
Default
-
0=False
Protection functions
(Equation 196)
(Equation 197)
(Equation 198)
(Equation 199)
(Equation 200)
Description
Three-phase currents
Block signal for acti-
vating the blocking
mode
783