Arcteq AQ-F255 User manual

AQ-F255
Feeder protection IED
Instruction manual


Table of contents
7
7
7
8
9
10
10
10
11
12
12
13
13
27
35
43
45
46
46
60
65
69
75
84
92
98
102
116
122
128
135
141
147
151
155
157
160
162
166
183
186
193
206
206
212
217
219
242
251
253
262
266
266
274
277
284
1. Manual revision notes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.1. Version 2 revision notes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.2. Version 1 revision notes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2. Abbreviations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3. General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4. IED user interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.1. Panel structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.1.1. AQ 250 series local panel structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.2. User level password conguration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5. Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.1. Functions included in AQ-F255 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.2. Measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.2.1. Current measurement and scaling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.2.2. Voltage measurement and scaling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.2.3. Power and energy calculation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.2.4. Frequency tracking and scaling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.3. General menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.4. Protection functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.4.1. General properties of a protection function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.4.2. Non-directional overcurrent I> (50/51) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.4.3. Non-directional earth fault I0> (50N/51N) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.4.4. Directional overcurrent IDir> (67) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.4.5. Directional earth fault I0Dir> (67N) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.4.6. Intermittent earth fault I0Int> (67NT) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.4.7. Current unbalance I2> (46) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.4.8. Harmonic overcurrent Ih> (50H/51H/68H) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.4.9. Circuit breaker failure protection CBFP (50BF) . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.4.10. Restricted earth fault / cable end differential (REF) I0D> (87N) . . . . . . . . . . . . . .
5.4.11. Overvoltage U> (59) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.4.12. Undervoltage U< (27) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.4.13. Neutral voltage U0> (59N) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.4.14. Sequence voltageU1/U2>/<(59P/27P/47) . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.4.15. Over- and underfrequencyf>/< (81O/81U) . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.4.16. Rate-of-change of frequency protection df/dt (81R) . . . . . . . . . . . . . . . . . . . . . .
5.4.17. Over power P> (32O) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.4.18. Under power P< (32U) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.4.19. Reverse power Pr (32R) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.4.20. Vector jump protection (78) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.4.21. Line thermal overload protectionTF> (49F) . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.4.22. Voltage memory function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.4.23. Arc fault protection IArc>/I0Arc>(50Arc/50NArc) . . . . . . . . . . . . . . . . . . . . . . . .
5.4.24. Programmable stage PGx >/< (99) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.5. Control functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.5.1. Setting group selection (SGS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.5.2. Object control and monitoring (OBJ) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.5.3. Indicator object monitoring (CIN) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.5.4. Auto-reclosing 0 → 1 (79) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.5.5. Cold load pick-up (CLPU) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.5.6. Switch on to fault (SOTF) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.5.7. Synchrocheck function ΔV/Δa/Δf (25) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.5.8. mA Output control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.6. Monitoring functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.6.1. Current transformer supervision (CTS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.6.2. Fuse failure VTS (60) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.6.3. Disturbance recorder (DR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.6.4. Measurement recorder . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
AQ-F255
Instruction manual
Version: 2.00
1 © Arcteq Relays Ltd

288
292
294
298
302
302
302
302
303
304
306
308
308
308
309
309
309
312
312
314
315
316
319
319
321
323
324
325
327
328
329
330
332
333
333
336
336
336
336
336
338
338
338
338
339
340
340
341
341
342
342
343
343
344
344
344
345
345
345
5.6.5. Circuit breaker wear-monitor (CBW) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.6.6. Fault locator (21FL) X → km . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.6.7. Total harmonic distortion monitor (THD) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.6.8. Measurement value recorder . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6. System integration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.1. Communication protocols . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.1.1. NTP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.1.2. ModbusTCP and ModbusRTU . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.1.3. ModbusIO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.1.4. IEC 61850 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.1.5. GOOSE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.1.6. IEC 103 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.1.7. DNP3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.1.8. IEC 101/104 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.1.9. SPA protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.2. General IO analog fault registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.3. Real time measurements to communication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7. Applications and connection examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7.1. Connections AQ-F255 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7.2. Example feeder application connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7.3. 3-phase, 3-wire ARON input connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7.4. Trip circuit supervision (95) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
8. Construction and installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
8.1. Construction and installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
8.2. CPU, IO and Power supply module . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
8.3. Current measurement module . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
8.4. Voltage measurement module . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
8.5. Binary input module (DI8) (option) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
8.6. Binary output module (DO5) (option) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
8.7. Arc protection module (option) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
8.8. RTD & mA input module (option) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
8.9. Serial RS232 communication module (option) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
8.10. LC100 Ethernet communication module (option) . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
8.11. mAout & mAinput module (option) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
8.12. Installation dimensioning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9. Technical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.1. Hardware . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.1.1. Measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.1.1.1. Power and energy measurement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.1.1.2. Current measurement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.1.1.3. Voltage measurement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.1.1.4. Frequency measurement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.1.2. CPU & Power supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.1.2.1. Auxiliary voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.1.2.2. CPU communication ports . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.1.2.3. CPU Binary inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.1.2.4. CPU Binary outputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.1.3. Option cards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.1.3.1. Binaryinput module . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.1.3.2. Binary output module . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.1.3.3. Arc protection module . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.1.3.4. mAout & mAin module . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.1.3.5. RTD & mA input module . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.1.3.6. RS232 & Serial ber communication module . . . . . . . . . . . . . . . . . . . . . .
9.1.3.7. Double LC100Mb Ethernet module(Redundant) . . . . . . . . . . . . . . . . . . .
9.1.4. Display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.2. Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.2.1. Protection functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.2.1.1. Non-directional overcurrent (50/51) I> . . . . . . . . . . . . . . . . . . . . . . . . . . .
AQ-F255
Instruction manual
Version: 2.00
© Arcteq Relays Ltd 2

345
346
347
348
349
350
351
351
352
352
353
354
355
355
356
357
357
358
358
359
359
359
359
360
360
361
362
362
362
363
363
363
364
364
365
367
369
9.2.1.2. Non-directional earth fault (50N/51N) I0> . . . . . . . . . . . . . . . . . . . . . . . .
9.2.1.3. Directional overcurrent (67) Idir> . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.2.1.4. Directional earth fault(67N) Iodir> . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.2.1.5. Intermittent earth fault (67NT) IoInt> . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.2.1.6. Current unbalance (46/46R/46L) I2> . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.2.1.7. Harmonic overcurrent (50H/51H, 68) Ih> . . . . . . . . . . . . . . . . . . . . . . . .
9.2.1.8. Circuit breaker failure protection (50BF/52BF) CBFP . . . . . . . . . . . . . . .
9.2.1.9. Restricted earth fault / Cable end differential (87N) Iod> . . . . . . . . . . . . .
9.2.1.10. Overvoltage (59) U> . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.2.1.11. Undervoltage (27) U< . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.2.1.12. Neutral overvoltage (59N) U0> . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.2.1.13. Sequence voltage(47/27PN/59PN) U1/2>/< . . . . . . . . . . . . . . . . . . . . .
9.2.1.14. Over-/Under frequency(81O/81U) f>/< . . . . . . . . . . . . . . . . . . . . . . . . .
9.2.1.15. Rate-of-change-frequency(81R) df/dt>/< . . . . . . . . . . . . . . . . . . . . . . .
9.2.1.16. Line thermal overload(49L) TF> . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.2.1.17. Over/Under/Reverse power protection(32/37) P>, P<, PREV> . . . . . . .
9.2.1.18. Resistance temperature detector alarm (49RTD) T> . . . . . . . . . . . . . . .
9.2.1.19. Vector jump (78) ΔΑ> . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.2.1.20. Arc protection (50ARC/50NARC) IARC> I0ARC> (option) . . . . . . . . . . .
9.2.2. Control functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.2.2.1. Setting group selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.2.2.2. Object control (OBJ) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.2.2.3. Autoreclosing function (79) 0 → 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.2.2.4. Cold load pick-up (CLP) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.2.2.5. Switch on to fault (SOTF) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.2.2.6. Synchrocheck (25) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.2.3. Monitoring functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.2.3.1. Current transformer supervision (CTS) . . . . . . . . . . . . . . . . . . . . . . . . . .
9.2.3.2. Fuse failure VTS (60) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.2.3.3. Disturbance recorder (DR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.2.3.4. Circuit breaker wear monitor (CBW) . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.2.3.5. Total harmonic distortion (THD) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.2.3.6. Fault locator (21FL) X → km . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.2.3.7. Voltage memory (integrated in 67,21G) . . . . . . . . . . . . . . . . . . . . . . . . . .
9.3. Tests and environmental . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
10. Ordering information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
11. Contact and reference information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
AQ-F255
Instruction manual
Version: 2.00
3 © Arcteq Relays Ltd

Disclaimer
Please read these instructions carefully before using the equipment or taking any other actions with
respect to the equipment. Only trained and qualied persons are allowed to perform installation,
operation, service or maintenance of the equipment. Such qualied persons have the responsibility to
take all appropriate measures, including e.g. use of authentication, encryption, anti-virus programs,
safe switching programs etc. necessary to ensure a safe and secure environment and usability of the
equipment. The warranty granted to the equipment remains in force only provided that the instructions
contained in this document have been strictly complied with.
Nothing contained in this document shall increase the liability or extend the warranty obligations of the
manufacturer Arcteq Relays Ltd. The manufacturer expressly disclaims any and all liability for any
damages and/or losses caused due to a failure to comply with the instructions contained herein or
caused by persons who do not full the aforementioned requirements. Furthermore, the manufacturer
shall not be liable for possible errors in this document. 
Please note that you must always comply with applicable local legislation and regulations. The
manufacturer gives no warranties that the content of this document is in all respects in line with local
laws and regulations and assumes no liability for such possible deviations.
You are advised to notify the manufacturer in case you become aware of any errors in this document or
of defects in the equipment.
The manufacturer reserves the right to update or amend this document at any time.
AQ-F255
Instruction manual
Version: 2.00
© Arcteq Relays Ltd 4

Copyright
Copyright © Arcteq Relays Ltd. 2018. All rights reserved.
AQ-F255
Instruction manual
Version: 2.00
5 © Arcteq Relays Ltd

1. Manual revision notes
1.1. Version 2 revision notes
Revision 2.00
Date 6.6.2019
Changes
- New more consistent look.
- Improved descriptions generally in many chapters.
- Improved readability of a lot of drawings and images.
- Updated protections included included in every IED manual.
- Every protection IED type now has connection drawing, application example drawingwith function block diagram
and application example with wiring.
- Added General-menu description.
1.2. Version 1 revision notes
Revision 1.00
Date 8.4.2013
Changes - The rst revision for AQ-F255 IED
Revision 1.01
Date 9.2.2017
Changes - Order code upgraded
- Programmable stage description added
Revision 1.02
Date 20.12.2017
Changes
- Measurement value recorder description
- ZCT connection added to current measurement description
- Internal harmonics blocking to I>,I0>,Idir>,I0dir> function descriptions
- Non-standard delay curves added
- Event lists revised on several functions
- RTD&mA card description improvements
- Auto-recloser function readability improvements
- Ring-lug CT card option description added
- Fault view description added
- New U> and U< function measurement modes documented
- Order code revised
Revision 1.03
Date 14.8.2018
Changes - Added mA output option card description and ordercode
- Added HMI display technical data
AQ-F255
Instruction manual
Version: 2.00
© Arcteq Relays Ltd 6

2. Abbreviations
CB – Circuit breaker
CBFP – Circuit breaker failure protection
CT – Current transformer
CPU – Central processing unit
EMC – Electromagnetic compatibility
HMI – Human machine interface
HW – Hardware
IED – Intelligent electronic device
IO – Input output 
LED – Light emitting diode
LV – Low voltage
MV – Medium voltage
NC – Normally closed
NO – Normally open
RMS – Root mean square
SF – System failure
TMS – Time multiplier setting
TRMS – True root mean square
VAC – Voltage alternating current
VDC – Voltage direct current
SW – Software
uP - Microprocessor
AQ-F255
Instruction manual
Version: 2.00
7 © Arcteq Relays Ltd

3. General
AQ-F255 Feeder Protection IED is a member of the AQ-200 product line. The AQ-200 protection
product line in respect of hardware and software is a modular concept. The hardware modules are
assembled and congured according to the application IO requirements and the software determines
the available functions. This manual describes the specic application of the AQ-F255 Feeder
Protection IED. For other AQ-200 series products please consult corresponding device manuals.
AQ-F255
Instruction manual
Version: 2.00
© Arcteq Relays Ltd 8

4. IED user interface
4.1. Panel structure
AQ 200 series IED user interface section is divided into hardware- and software user interface
sections. Software interface is divided into local panel conguration and programming by using
AQtivate 200 freeware software suite.
4.1.1. AQ 250 series local panel structure
AQ 200 series IED have multiple LEDs, control buttons, function buttons and local RJ-45 Ethernet port
for conguration on front as a default. On rear each unit is equipped with RS-485 serial interface and
RJ-45 Ethernet interface options as a standard. See list below.
Figure. 4.1.1. - 1. Local panel structure.
4 default LEDs for free conguration: Power, Error, Start and Trip.
16 freely congurable LEDs with programmable legend texts.
3 object control buttons: Choose the controllable object with Ctrl –button, control breaker with
0- and I push buttons.
L/R push button for local remote control.
7 Navigation buttons for IED local programming and a button for password activation.
12 freely congurable function buttons.
RJ-45 Ethernet port for IED conguration.
Used views are freely congurable with buttons for changing settings groups or controlling the relays
logic in general. Object status (Circuit breaker/Disconnector) can be displayed on the screen. All
measured and calculated values (currents, voltages, power, energy, frequency etc.) can be shown in
the screen.
AQ-F255
Instruction manual
Version: 2.00
9 © Arcteq Relays Ltd

4.2. User level password conguration
As a factory default IEDs do not have any user levels locked behind passwords. In order to activate
different user levels click the IED HMI lock button and set the desired passwords for different user
levels.
NOTE: Passwords can be set only at local HMI.
In the HMI the user level currently in use is indicated in the upper right corner with stars.
Different user levels and the indicators are:
SUPERUSER (***) = full access including congurations
CONFIGURATOR (**) = access to all settings
OPERATOR (*) = access to limited settings and control
USER ( - ) = view only
You can set a new password for the user level by selecting the key icon next to the user level. After this
you can lock the user level by pressing return key while the lock is selected. If you need to change the
password you can select the key icon again and give a new password. Please note that in order to do
this the user level must be unlocked.
The required access level required to change a parameter is indicated with star (*) symbol if such is
required. As a general rule the access levels are divided as follows:
User: Can view any menus and settings but cannot change any settings nor operate breakers
or other equipment.
Operator: Can view any menus and settings but cannot change any settings BUT can operate
breakers or other equipment.
Congurator: Can change most settings like basic protection pick-up levels or time delays,
breaker control functions, signal descriptions etc. Can operate breakers or other equipment.
Super user: Access to change any setting and can operate breakers or other equipment.
AQ-F255
Instruction manual
Version: 2.00
© Arcteq Relays Ltd 10

5. Functions
5.1. Functions included in AQ-F255
This chapter presents the functions of AQ-F255 Feeder Protection relay. AQ-F255 includes following
functions and amounts of instances of the functions.
Table. 5.1. - 1. Protection functions of AQ-F255
Name IEC ANSI Description
NOC1
NOC2
NOC3
NOC4
I>
I>>
I>>>
I>>>>
50/51 Overcurrent protection (4 stages)
NEF1
NEF2
NEF3
NEF4
I0>
I0>>
I0>>>
I0>>>>
50N/51N Residual overcurrent protection (4 stages)
DOC1
DOC2
DOC3
DOC4
IDir>
IDir>>
IDir>>>
IDir>>>>
67 Directional overcurrent protection (4 stages)
DEF1
DEF2
DEF3
DEF4
I0Dir>
I0Dir>>
I0Dir>>>
I0Dir>>>>
67N Directional residual overcurrent protection (4 stages)
IEF1 I0Int> 67NT Intermittent earth fault
CUB1
CUB2
CUB3
CUB4
I2>
I2>>
I2>>>
I2>>>>
46/46R/46L Negative sequence overcurrent / phase current reversal / unbalance
protection (4 stages)
HOC1
HOC2
HOC3
HOC4
Ih>
Ih>>
Ih>>>
Ih>>>>
50h/51h/68h
Detection and blocking or tripping from selectable 2nd, 3rd, 4th, 5th, 7th,
9th, 11th, 13th, 15th, 17th, 19th harmonic. Phase currents and residual
currents separate stages. (4 stages)
CBF1 CBFP 50BF/52BF Breaker failure protection
REF1 I0d> 87N Low or high impedance restricted earth fault, cable end differential
protection
TOLF1 TF> 49L Feeder thermal overload protection
OV1
OV2
OV3
OV4
U>
U>>
U>>>
U>>>>
59 Overvoltage protection (4 stages)
UV1
UV2
UV3
UV4
U<
U<<
U<<<
U<<<<
27 Undervoltage protections (4 stages)
VUB1
VUB2
VUB3
VUB4
U1&U2>/<
U1&U2>>/<<
U1&U2>>>/<<<
U1&U2>>>>/<<<<
59P/27P/47 Sequence voltage protection (4 stages)
NOV1
NOV2
NOV3
NOV4
U0>
U0>>
U0>>>
U0>>>>
59N Neutral voltage protection (4 stages)
OPW1 P> 32O Over power
UPW1 P< 32U Under power
RPW1 Pr 32R Reverse power
AQ-F255
Instruction manual
Version: 2.00
11 © Arcteq Relays Ltd

FRQV1
f>
f>>
f>>>
f>>>>
f<
f<<
f<<<
f<<<<
81O/81U Frequency protection (8 stages)
ROCOF1 df/dt >/< (1…8) 81R Rate of change of frequency (8 stages)
VJP1 ∆φ 78 Vector jump
PGS1 PGx >/< 99 Programmable stage
ARC1 IArc>/I0Arc> 50Arc/50NArc Arc protection (Option)
Table. 5.1. - 2. Control functions of AQ-F255
Name IEC ANSI Description
SG - - Set group settings
OBJ - - Object control
AR 0 →1 79 Autoreclosing function
CLP CLPU - Cold load pick-up
SOF SOTF - Switch on to fault logic
SYN ΔV/Δa/Δf 25 Synchrocheck function
Table. 5.1. - 3. Monitoring functions of AQ-F255
Name IEC ANSI Description
CTS - - Current transformer supervision
VTS - 60 Fuse failure
DR - - Disturbance recorder
CBW - - Circuit breaker wear monitor
THD - - Total harmonic distortion
FLOC - 21FL Fault locator
VREC - - Measurement value recorder
5.2. Measurements
5.2.1. Current measurement and scaling
Current measurement module (CT-module) is used for measuring the currents from current
transformers and processing the measured values to measurement database and for measurement-
and protection functions to use. For the measurements to be correct it is essential to understand the
concept of the current measurements.
AQ-F255
Instruction manual
Version: 2.00
© Arcteq Relays Ltd 12

Figure. 5.2.1. - 2. Current measurement terminology
For the measurements to be correct it needs to be made sure that the measurement signals are
connected to correct inputs, current direction is connected with correct polarity, and the scaling is set
according to current transformer nominal values.
Relay calculates scaling factors based on the set CT primary, secondary and nominal current values.
Relay measures secondary current which in this case mean the current output from the current
transformer which is installed into the primary circuit of the application. In order the relay to “know”
primary and per unit values current transformer rated primary and secondary currents need to be set.
In case of motor or any specic electrical apparatus protection application motor nominal current
should be set too in order for the values to be per unitized to apparatus nominal and not to CT nominal
(This is not absolutely mandatory, in some relays it is still needed to calculate correct settings manually.
Setting the relay nominal current makes the motor protection a lot easier and straight forward. In
modern protection devices this scaling calculation is done internally after the current transformer
primary, secondary and motor nominal currents are given).
Normally the primary current ratings for phase current transformers are 10A, 12.5A, 15A, 20A, 25A,
30A, 40A, 50A, 60A and 75A and their decimal multiples, while normal secondary current ratings are 1
and 5A. Other, non-standard ratings can be directly connected since the scaling settings are flexible in
large ranges. As an example, ring core current transformer ratings may be different. Ring core current
transformers are commonly used for sensitive earth fault protection and their rated secondary may be
as low as 0.2 A in some cases.
In following chapter is an example for setting the scaling of the current measurements to the example
current transformer and system load.
AQ-F255
Instruction manual
Version: 2.00
13 © Arcteq Relays Ltd

CT scaling example
The connection of CTs to the IED measurement inputs and the ratings of the current transformers and
load nominal current are as in following gure.
Figure. 5.2.1. - 3. Example connection.
Initial data of the connection and the ratings are presented in following table.
Table. 5.2.1. - 4. Initial data from example connection.
Phase current CT:
CT primary 100A
CT secondary 5A
Ring core CT in Input I02:
I0CT primary 10A
I0CT secondary 1A
Load nominal 36A
Phase currents are connected to summing “Holmgren” connection into the I01 residual input.
Phase current CT secondary currents starpoint is towards the line.
For the scaling of the currents to per unit values for the protections selection needs to be made now if
the protected object nominal current or the CT primary value should be the base for per unitizing.
If the per unit scaling is wanted to be according to the CT values then “Scale meas to In” is set to “CT
nom p.u.” As presented in the gure below.
AQ-F255
Instruction manual
Version: 2.00
© Arcteq Relays Ltd 14

Figure. 5.2.1. - 4. Phase current transformer scalings to CT nominal.
After the settings are input to the IED, scaling factors are also calculated and displayed for the user.
Scaling factor P/S tells the CT primary to secondary ratio, CT scaling factor to NOM tells the scaling
factor to nominal current (in this case it should be 1 since the selected nominal current is the phase CT
nominal). Per unit scaling factors to primary and secondary values are also shown. In this case the
scaling factors are directly the set primary and secondary currents of the set CT.
If the settings would be wanted to be scaled to load nominal then the selection “Scale meas to In”
would be set to “Object In p.u.”
Figure. 5.2.1. - 5. Phase current transformer scalings to protected object nominal current.
AQ-F255
Instruction manual
Version: 2.00
15 © Arcteq Relays Ltd

When measurement scaling is made to the protected object nominal current, the object nominal
current needs also to be set into the “Nominal current In” input. The differences in the used scaling
factors can now be seen. Primary to secondary ratio is directly the ratio of the set CT ratios, CT scaling
factor to nominal is now the set CT primary to nominal current ratio, per unit scalings to primary is
changed now to nominal current and the secondary per unit factor is calculated accordingly to the
given ratio of CT primary to object nominal current.
If coarse residual current (I01) is wanted to be used for CT sum (Holmgren) input then it should be set
to phase current CT ratings 100/5A.
Figure. 5.2.1. - 6. Residual current I01 scaling to summing connection.
For the sensitive residual current (I02) measurement is set directly 10/1A rated currents.
Figure. 5.2.1. - 7. Residual current I02 scaling to ring core CT input.
If the scaling was made to CT primary or to object nominal current the measurements will look as
follows with nominal current feeding:
Figure. 5.2.1. - 8. Scalings to CT nominal.
AQ-F255
Instruction manual
Version: 2.00
© Arcteq Relays Ltd 16

Figure. 5.2.1. - 9. Scalings to protected object nominal current.
As seen from the examples the primary and secondary currents will be displayed as actual values so
the scaling selection does not have effect to that. Only effect is now that the per unit system in the relay
is scaled to either transformer nominal or the protected object nominal and this makes the settings
input for the protected object straight forward.
ZCT scaling example
Figure. 5.2.1. - 10. If zero sequence current transformer is used it should be connected to I02 channel which has lower CT
scaling ranges.
Figure. 5.2.1. - 11. Setting example of zero sequence current transformer application.
AQ-F255
Instruction manual
Version: 2.00
17 © Arcteq Relays Ltd

Figure. 5.2.1. - 12. With current transformer ratio of 200mA/1.5mA earthfault protection setting 1*I0n will make the function pick-
up at 200mA primary current.
Troubleshooting
It is possible that for some reason the measured currents may not be as expected. For these cases
following checks may be helpful.
Problem Check / Resolution
Measured current amplitude
in all phases does not
match for what is injected.
Scaling settings may be wrong, check from Measurement, Transformers, Phase CT scaling that
the settings match for what is expected. Also check that the scaling measurement to In is set
accordingly either to “Object In“or CT nominal. If working with CT:s, if possible check the actual
ratings from the CT:s as well, since in some cases the actual CT:s may have been changed
from the original plan for some reason.
Measured current amplitude
does not match for one
measured phase or
calculated I0 is measured
when there should not be
any.
Check wiring connections from injection device or CTs to the IED. NOTE: If working with CTs
which are in energized system extreme caution should be practiced when checking
connections. Opened CT secondary circuit may generate dangerously high voltages. “Buzzing”
sound from connector can indicate open circuit.
Measured current
amplitudes are all ok and
equal but the angles are
strange.
Phase unbalance protection
trips immediately when it is
activated.
Earth fault protection trips
immediately when it is
activated.
Phase currents are connected into the measurement module, but the order or polarity of one or
all phases is incorrect.
Go to Measurement, Phasors and check the current Phasors diagram.
When all is correctly connected the diagram should look as below with symmetric feeding:
In following rows few most common cases are presented.
AQ-F255
Instruction manual
Version: 2.00
© Arcteq Relays Ltd 18

Table. 5.2.1. - 5. Phase polarity problems are easy to nd since the vector diagram points out the opposite polarity in the wrongly
connected phase.
Phase L1 (A) polarity incorrect.
Phase currents
IL1: 1.00 xIn / 0.00 deg
IL2: 1.00 xIn / 60.00 deg
IL3: 1.00 xIn / 300.00 deg
Sequence currents
I1: 0.33 xIn / 180.00 deg
I2: 0.67 xIn / 0.00 deg
I0Calc: 0.67 xIn / 0.00 deg
Resolution:
- Change wires to opposite in CT module connectors 1 – 2
- Or from the Transformers, Phase CT scaling select IL1 polarity to “Invert”.
Phase L2 (B) polarity incorrect.
Phase currents
IL1: 1.00 xIn / 0.00 deg
IL2: 1.00 xIn / 60.00 deg
IL3: 1.00 xIn / 120.00 deg
Sequence currents
I1: 0.33 xIn / 0.00 deg
I2: 0.67 xIn / -60.00 deg
I0Calc: 0.67 xIn / 60.00 deg
Resolution:
-Change wires to opposite in CT module connectors 3 – 4
-Or from the Transformers, Phase CT scaling select IL2 polarity to “Invert”.
Phase L3 (C) polarity incorrect.
Phase currents:
IL1: 1.00 xIn / 0.00 deg
IL2: 1.00 xIn / 240.00 deg
IL3: 1.00 xIn / 300.00 deg
Sequence currents:
I1: 0.33 xIn / 0.00 deg
I2: 0.67 xIn / 60.00 deg
I0Calc: 0.67 xIn / -60.00 deg
Resolution:
-Change wires to opposite in CT module connectors 5 – 6
-Or from the Transformers, Phase CT scaling select IL3 polarity to “Invert”.
AQ-F255
Instruction manual
Version: 2.00
19 © Arcteq Relays Ltd