ABB REC650 - Zero Sequence Based

3 2
3 2 100= ×
V
V PU
VBase
EQUATION1757-ANSI V3 EN (Equation 86)
where:
3V2PU is the maximal negative sequence voltage during normal operation conditions, plus a margin of
10...20%
VBase is setting of the global base voltage for all functions in the IED.
The setting of the current limit 3I2PU is in percentage of global parameter IBase. The
setting of 3I2PU must be higher than the normal unbalance current that might exist in the
system and can be calculated according to equation 87.
3 2
3 2 100= ×
I
I PU
IBase
EQUATION1758-ANSI V3 EN (Equation 87)
where:
3I2 is the maximal negative sequence current during normal operating conditions, plus a margin of
10...20%
IBase is the setting of base current for the function
9.2.3.4 Zero sequence based
The relay setting value 3V0PU is given in percentage of the global parameter VBase. The
setting of 3V0PU should not be set lower than according to equation 88.
3 0
3 0 100= ×
V
V PU
VBase
EQUATION1759-ANSI V3 EN
(Equation 88)
where:
3V0 is the maximal zero sequence voltage during normal operation conditions, plus a margin of 10...20%
VBase is setting of global base voltage all functions in the IED.
The setting of the current limit 3I0PU is done in percentage of the global parameter
IBase. The setting of 3I0PU must be higher than the normal unbalance current that might
exist in the system. The setting can be calculated according to equation 89.
1MRK 511 286-UUS A Section 9
Secondary system supervision
175
Application manual