1BPROTECTION FUNCTIONS
PROTECTION, CONTROL AND METERING FUNCTIONS
Once configured the 67/67N function, it is possible to properly configure the 50/50N
and 51/51N functions since the configuration screens change slightly for the different
operating modes (non directional, forward/backward directional and bidirectional)
50 and 51 function screens are tab based. The different directional mode settings are
changed in the corresponding tab.
Non directional: In this case, only one tab is shown.
Forward or backward directional: In this case only a tab is shown again, but the
text will change to “Forward settings” or “Backward settings”.
Bidirectional: Two tabs are shown, one with “Forward settings” text and the
other with “Backward settings” text.
2.1.4.3. PHASE TO GROUND
It is the fault of one of the phases to ground. In this kind of faults the polarization
voltage selection includes:
Zero sequence voltage.
Negative sequence voltage.
For lines with small source impedance the sequence voltages are too small
and are not enough for the protection to operate correctly. To solve this
situation the voltage is compensated with a factor equal to kI2 for negative
sequence and kIo for zero sequence k being 25% of the line impedance or
1.05 if series compensation is being used. Even with this compensation the
voltage may be too small in which case the protection will send or block the
signal depending on its configuration.
Quadrature voltage. Here the faulted phase current is used along with the
compound voltage derived from the non-faulted phases. E.g. For a fault in
phase A the VBC is used. For a fault in B the VCA voltage is used and so on.
The selected voltage is in quadrature (90degrees) with the place where the
faulted phase should be, hence the “Quadrature Voltage” term. Before the
comparison of this voltage’s angle with that of the faulted phase 90 degrees
are added to it so it aligns itself with the faulted phase voltage.
Summary of Contents for smART P500
Page 1: ...Instruction Manual Multifunction Protection Relay smART P500...
Page 23: ...2BTABLES INDEX THIS PAGE HAS BEEN LEFT BLANK INTENTIONALLY...
Page 39: ...5BHARDWARE FEATURES INTRODUCTION Figure 1 9 Wye Wye Connection measured neutral...
Page 40: ...5BHARDWARE FEATURES INTRODUCTION Figure 1 10 Wye Wye Connection sensitive neutral...
Page 41: ...5BHARDWARE FEATURES INTRODUCTION Figure 1 11 Open Delta Connection measured neutral...
Page 42: ...5BHARDWARE FEATURES INTRODUCTION Figure 1 12 Open Delta Connection sensitive neutral...
Page 511: ...2BANSI CURVES 0BCURVES FOR TIME CHARACTERISTICS Figure I 6 Moderately ANSI curve...
Page 513: ...2BANSI CURVES 0BCURVES FOR TIME CHARACTERISTICS Figure I 7 Very inverse ANSI curve...
Page 515: ...2BANSI CURVES 0BCURVES FOR TIME CHARACTERISTICS Figure I 8 Extremely inverse ANSI curve...
Page 532: ...4BRECLOSER CURVES 0BCURVES FOR TIME CHARACTERISTICS Figure I 14 Recloser Curves 101 119...
Page 535: ...4BRECLOSER CURVES 0BCURVES FOR TIME CHARACTERISTICS Figure I 15 Recloser Curves 120 142...
Page 538: ...4BRECLOSER CURVES 0BCURVES FOR TIME CHARACTERISTICS Figure I 16 Recloser Curves 151 202...