
NA10 - Manual - 04 - 2022
3.9 METERING..........................................................................................................................................................................................................25
Accuracy (type tests)....................................................................................................................................................................................25
Measures........................................................................................................................................................................................................25
4 FUNCTION CHARACTERISTICS 26
4.1 HARDWARE DESCRIPTION.............................................................................................................................................................................26
Power supply board......................................................................................................................................................................................27
CPU board.......................................................................................................................................................................................................27
Input board .....................................................................................................................................................................................................27
MMI (keyboard, LED and display) ..............................................................................................................................................................27
4.2 SOFTWARE DESCRIPTION ............................................................................................................................................................................. 28
Base software............................................................................................................................................................................................... 28
Real-time operating system........................................................................................................................................................................ 28
Task ................................................................................................................................................................................................................. 28
Drivers............................................................................................................................................................................................................ 29
Application Software................................................................................................................................................................................... 29
Data Base...................................................................................................................................................................................................... 29
Self test (Application) .................................................................................................................................................................................. 29
Development tools (Builder)....................................................................................................................................................................... 29
4.3 I/O DESCRIPTION............................................................................................................................................................................................. 30
Metering inputs ............................................................................................................................................................................................ 30
Signal processing......................................................................................................................................................................................... 30
Conventions................................................................................................................................................................................................... 33
Use of measured values...............................................................................................................................................................................34
Binary inputs ..................................................................................................................................................................................................35
Output relays................................................................................................................................................................................................. 40
LED indicators................................................................................................................................................................................................42
Communication interfaces...........................................................................................................................................................................44
4.4 PROTECTIVE ELEMENTS .................................................................................................................................................................................45
Rated values...................................................................................................................................................................................................45
Thermal protection with RTD thermometric probes - 26 ........................................................................................................................47
Thermal image - 49....................................................................................................................................................................................... 49
Phase overcurrent - 50/51........................................................................................................................................................................... 60
Residual overcurrent - 50N/51N ................................................................................................................................................................ 70
Residual overvoltage - 59N......................................................................................................................................................................... 80
Ground directional overcurrent - 67N........................................................................................................................................................84
Breaker failure - BF.....................................................................................................................................................................................107
4.5 CONTROL AND MONITORING..................................................................................................................................................................... 109
Logical block - BLOCK1............................................................................................................................................................................. 109
Selective block - BLOCK2 ..........................................................................................................................................................................111
Internal selective block -BLOCK4.............................................................................................................................................................116
Remote tripping ...........................................................................................................................................................................................117
Frequency tracking.................................................................................................................................................................................... 118
Second Harmonic Restraint - 2ndh-REST .............................................................................................................................................. 119
Cold Load Pickup - CLP ............................................................................................................................................................................. 120
CT supervision - 74CT .................................................................................................................................................................................122
Trip circuit supervision - 74TCS................................................................................................................................................................ 123
Circuit breaker supervision .......................................................................................................................................................................126
Demand measures..................................................................................................................................................................................... 129
Oscillography ............................................................................................................................................................................................. 129
5 MEASURES, LOGIC STATES AND COUNTERS 130
Measures..................................................................................................................................................................................................... 130
Protection .................................................................................................................................................................................................... 130
Delayed inputs............................................................................................................................................................................................ 130
Internal states............................................................................................................................................................................................. 130
Relays............................................................................................................................................................................................................131
Counters........................................................................................................................................................................................................131
Self test .........................................................................................................................................................................................................131
Pilot wire diagnostic ...................................................................................................................................................................................132
Selective Block - BLOCK2..........................................................................................................................................................................132
Fault recording - SFR..................................................................................................................................................................................132
Event recording - SER................................................................................................................................................................................ 133
Oscillography - DFR ................................................................................................................................................................................... 133
6 INSTALLATION 135
6.1 PACKAGING.....................................................................................................................................................................................................135
6.2 MOUNTING......................................................................................................................................................................................................135
6.3 ELECTRICAL CONNECTIONS ....................................................................................................................................................................... 139