36
If setting equilibrium factor on high voltage side to be 1, and convert other sides to high
voltage side, its calculation formula is as follows:
K1=1
K2=U2n*CT2/(*U1n*CT1)
K3=1.732*U3n*CT3/(U1n*CT1)
c) Calculating equilibrium factor in terms of rated current is as following:
K1=1
K2=Ie1/Ie2
K3=Ie1/Ie3
In which
：
K1
、
K2
、
K3 — equilibrium factor on Transformer I
、
II
、
III side
Ie1
、
Ie2
、
Ie3 — secondary rated current on Transformer I
、
II
、
III side
U1n
、
U2n
、
U3n — primary rated voltage on Transformer I
、
II
、
III side
CT1
、
CT2
、
CT3 — CT transformation ratio on Transformer I
、
II
、
III side
Note
：
Equilibrium factor of differential protection are not all the same, the calculating mode of
some protections may not be the same as the above-mentioned one. Please refer to
corresponding instruction when doing the test.
4
The current phase of two sides
the connection type of the transformer
I1 phase
I2 phase
Y/Y-12
0°
180°or 0°
Y/Δ-11
0°
180°or 0°
Y/Δ-1
0°
180°or 0°
(4) The switch quantity
Let the output terminal of the protection contact to the No.1 channel of the switch quantity.
Generally is normally open contact. Contact jitter delay is 10ms.
(5) Connecting mode
1
Connecting mode of six-phase ratio control
Summary of Contents for HT-802
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