Toshiba GR-200 Series Instruction Manual page 7

Reset Ratio ........................................................................................................................... 79
2.4.4
Miscellaneous functions ...................................................................................................... 79
2.4.5
Setting for Petersen coil earthed system ............................................................................ 80
2.4.6
Setting of standby earth-fault ............................................................................................. 81
2.4.7
Scheme logic ........................................................................................................................ 81
2.4.8
Setting .................................................................................................................................. 84
2.4.9
Signal ................................................................................................................................... 89
2.4.10
Negative sequence overcurrent protection (OCN) ..................................................................... 91
Relay polarity ...................................................................................................................... 91
2.5.1
Inverse time and definite time delay characteristic .......................................................... 93
2.5.2
Threshold value ................................................................................................................... 99
2.5.3
Reset Ratio ........................................................................................................................... 99
2.5.4
Miscellaneous functions ...................................................................................................... 99
2.5.5
Scheme logic ...................................................................................................................... 100
2.5.6
Setting ................................................................................................................................ 102
2.5.7
Signal ................................................................................................................................. 107
2.5.8
Undercurrent protection (UC) .................................................................................................. 109
Operation and characteristic ............................................................................................. 110
2.6.1
Miscellaneous functions ..................................................................................................... 110
2.6.2
Scheme switch .................................................................................................................... 110
2.6.3
Setting ................................................................................................................................. 112
2.6.4
Signal .................................................................................................................................. 113
2.6.5
Switch on to fault (SOTF-OC) ................................................................................................... 114
Scheme logic ....................................................................................................................... 114
2.7.1
Setting ................................................................................................................................. 116
2.7.2
Signal .................................................................................................................................. 116
2.7.3
Broken conductor protection (BCD) .......................................................................................... 117
Equivalent circuit for a one-phase series fault ................................................................. 118
2.8.1
Characteristic and setting ................................................................................................. 120
2.8.2
Miscellaneous functions .................................................................................................... 120
2.8.3
Scheme logic ...................................................................................................................... 121
2.8.4
Setting ................................................................................................................................ 122
2.8.5
Signal ................................................................................................................................. 122
2.8.6
Thermal overload function (THM) ........................................................................................... 123
Thermal state determination ............................................................................................ 124
2.9.1
Thermal characteristic ...................................................................................................... 125
2.9.2
Scheme logic ...................................................................................................................... 126
2.9.3
Setting ................................................................................................................................ 127
2.9.4
Signal ................................................................................................................................. 127
2.9.5
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6F2T0200 (0.15)