Signals - ABB RELION REX640 Technical Manual

1MRS759142 C
4.3.5.10
REX640
Technical Manual
The required knee-point voltage can be calculated using equation
U = 2 · ( 4620 A / 1000 ) · ( 15.3 + 1.46 ) ≈ 155 V.
k
The value 155 V is lower than the value 323 V, which means that the value of U
high enough.
As mentioned earlier, I
m
= 0 and I = m · 0.5 · I
rs e
I = n · m · I = 1000 · 4 · 0.012 A = 48 A ( ≈ 6 % x I
prim e
I = 4 · 0.5 · 0.012 A = 0.024 A.
rs
The setting value can be calculated with:
I

rs
Operatevalue
=
 
I
CT _ 2 n

GUID-580CD6F0-CDC3-482D-851C-C04DF89ADABE V1 EN
The resistance of the stabilizing resistor can now be calculated:
R = U / I = 78 V / (2 · I
s s rs
Example 2b
In this example, I = 4 x 12 mA = 48 mA and I
rs
I = n · ( I + I + m · I
prim rs u
The setting value can be calculated with:
I

rs
Operatevalue
=
 
I
CT n
_ 2

GUID-375769B3-415F-4EE6-A2E7-26800614C303 V1 EN
The resistance of the stabilizing resistor is now:
R = U / I = 78 V / 48 mA ≈ 1630 Ω
s s rs
In this example, the relay is of such a type that the stabilizing resistor can be chosen
freely.

Signals

Table 615: HREFPDIF Input signals
Name Type
IRES SIGNAL
BLOCK BOOLEAN
= 0.5 · I gives a realistic value for I
e
, the value for the sensitivity is:
A
0 024 .

 
2 4 . %
  =  ≈

1 A
 

) = 78 V / (2 · 0.012 A) = 3250 Ω.
e
= 30 mA. This results in the sensitivity:
u
) = 1000 · (48 + 30 + 24) mA = 102 A
m
0 048 . A

 
4 8 . %
  =  ≈

A
1
 

Default Description
- Residual current
0=False Block signal for activating the blocking mode
Section 4
Protection functions
in Equation 132. If I
prim
).
n
(Equation 139)
(Equation 140)
is
k
u
685