ABB Relion 670 series, Technical Manual

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IEC99000530-2-en.vsdx
Y
t
Value Reported
(1st)
Y1
Value
Reported
A1 Y2
Value
Reported
Y3
Y4
A
Value
Reported
A2
Y5
A3
A4
A5
A7
A6
Value
Reported
A2 >=
pre-set value
A1 >=
pre-set value
A >=
pre-set value
A3 + A4 + A5 + A6 + A7 >=
pre-set value
IEC99000530 V2 EN-US
Figure 193: Reporting with integral dead-band supervision
Measurement ZMMXU
GUID-2DB6F5A4-A3C2-4BBA-8327-393B7F89EDC6 v1
The magnitude and angle of the impedance for each phase are available on the outputs (
ZLxMAG
and
ZLxANGL (x=1,2,3)). Each analogue output has a corresponding supervision level output
( ZLxRANG, ZLxANGR). The supervision output signal is an integer in the interval 0-4, see section
“Measurement supervision”.
Impedance measurement is calculated based on
V
A
/
I
A
,
V
B
/
I
B
,
V
C
/
I
C
, where
V
X
and
I
X
are
phase-to-ground voltage and phase-to-ground current.
When the operating current is too low, the impedance measurement can be erroneous. In order to
avoid such error, minimum operating current will be checked. For phase currents lower than 3% of
IBase, the magnitude of impedance is force to 9999999 and the angle is forced to 0 degree.
Inside the function, to ensure the readability of the output for the users,
ZLxMAG and ZLxANGL
(x=1,2,3) will not change more often than a certain time period, for example, every 100 ms.
Section 7 1MRK 502 066-UUS B
Impedance protection
366
Technical manual