ABB ret650, Руководство по применению

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100
2
2 3
 
IBase
I
I
EQUATION1520 V5 EN-US
(Equation 41)
where:
I2
is the maximal negative sequence current during normal operating conditions, plus a margin
of 10...20%
IBase
is the base current for the function according to the setting
GlobalBaseSel
10.2.3.4 Zero sequence based
M13683-43 v8
The IED setting value 3U0> is given in percentage of the base voltage UBase . The
setting of 3U0> should not be set lower than the value that is calculated according
to equation 42 .
100
3
0 3
0 3
 
UBase
U
U
EQUATION1521 V4 EN-US
(Equation 42)
where:
3U0
is the maximal zero sequence voltage during normal operation conditions, plus a margin of
10...20%
UBase is the base voltage for the function according to the setting
GlobalBaseSel
The setting of the current limit 3I0< is done in percentage of IBase . The setting of
3I0< must be higher than the normal unbalance current that might exist in the
system. The setting can be calculated according to equation 43 .
3 0
3 0 100
I
I
IBase
= ×
<
EQUATION2293 V3 EN-US
(Equation 43)
where:
3I0<
is the maximal zero sequence current during normal operating conditions, plus a margin of
10...20%
IBase
is the base current for the function according to the setting
GlobalBaseSel
10.2.3.5 Delta U and delta I
GUID-02336F26-98C0-419D-8759-45F5F12580DE v7
Set the operation mode selector OpDUDI to On if the delta function shall be in
operation.
1MRK 504 169-UEN A
Section 10
Secondary system supervision
Transformer protection RET650 2.2 IEC 173
Application manual