Toshiba GR-200 Series Instruction Manual page 98

Summary of SEF operation
(vii)
Table 2.4-3 shows a summary for SEF operation. Note that DEF will be set unconditionally in
IEC-NI, VI, EI and UK-LTI characteristics (†).
Table 2.4-3 Type and standard board in the SEF1 (A tick represents a selectable function)
DT
Characteristics
DT
IEC-NI
IEC-VI
IEC-EI
UK LTI
IEEE-MI
IEEE-VI
IEEE-EI
US-CO2
US-CO8
Original
N.A
DEF
N.A
N.A
N.A
DEP
N.A
N.A
N.A
Threshold level for operation
2.4.3
The value of threshold current at which the SEF (I
settings; the setting [SEF1] is provided for both the IDMT and the DT characteristic. Note that
the settings of the threshold levels are allowed to have distinct values in the respective SEF
elements.
Reset Ratio
2.4.4
The ratio of the threshold current for pick-up to reset is applied using a setting; for example,
the ratio for the SEF1 element is set using the setting [SEF1-DPR]. The reset ratios for the
other EF elements are also provided.
Miscellaneous functions
2.4.5
Blocking SEF by ICD
(i)
The operation of each SEF element can be blocked if the ICD function detects a second
harmonic current caused by the magnetizing inrush current phenomenon when a transformer
is energized. For example, for the SEF1 element, the scheme switch [SEF1-2fBlk] is provided,
and Block should be set when the user wishes to block the SEF1 element when the second
IEC-NI IEC-VI IEC-EI
✓
✓
✓
✓
✓† ✓† ✓†
IDMT
UK-LTI IEEE-MI IEEE-VI
✓
✓
✓
✓† ✓ ✓
✓
✓
) element will pick-up is configured by
SEF
- 79 -
6F2T0200 (0.15)
IEEE-EI US-CO2 US-CO8
✓
✓
✓
✓ ✓ ✓
✓
✓
✓
GRE200 (1,2)
Original
✓
✓
✓