ABB RELION REB500 Technical Manual page 61

1MRK 505 406-UEN B
Z
L 1
Z
L
Z
L 3
All uncompensated impedances Z
and temporarily set the logical signals Ph and E (no display). An impedance loop is selected on
the basis of these signals (loop = selected phase).
Phase-ground-loop
For a phase-ground-loop, the impedance is calculated with a compensation factor k
Z
Ph 0
For example:
Z
L10
Phase-to-phase loop
For a phase-to-phase loop, the impedance is calculated using phase-to-phase variables:
Z
Ph Ph
For example:
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Technical manual
U

L 1 (uncompensated)
I
L 1
U

L 2
(uncompensated)
2
2 I
L 2
U
L 3
(uncompensated)
I
L 3
U


Ph 0

 
I 1 I
Ph E
U

L
1
 
I 1 I
L 1 E
U


Ph Ph

I

Ph Ph
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, Z and Z are compared with the starting characteristic
L1 L2 L3
Section 5
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= 1:
0
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