Engineer aratohu
Te arotake hoahoa, te whakaputa taunakitanga me te whakataurite i ngā rahi taura kōwhiri mō tētahi mahi.
- 4 meneti te pānuiCar-park floodlight: obtrusive light at a boundaryTwo 10 000 lm floodlights 10 m from a neighbour's window in zone A2, checked against AS/NZS 4282 for lux at the window, candela and the upward light ratio.
- 3 meneti te pānuiGenerator fault current calculation at 400 VA 500 kVA 400 V standby set at 12 % subtransient reactance gives 721.69 A full load and 6014.07 A fault current, with the decay the figure leaves out.
- 3 meneti te pānuiIEEE 1584-2002: arc flash model and limitsWhat the IEEE 1584-2002 empirical model governs, where it stops applying, and a 400 V switchboard study that lands on 7.54 cal/cm² at 455 mm.
- 5 meneti te pānuiArc flash at a 48 V home batteryClass a 48 V lithium home battery with 6 kA at its terminals by AS/NZS 5139, find its arc flash energy and PPE level, then bring it down with fuses.
- 3 meneti te pānuiIEC 60255-151: IDMT curve constantsWhat IEC 60255-151 governs, which curve sets the IDMT tool carries, and a worked grading pair on standard inverse that clears in 0.21 s and 0.74 s.
- 3 meneti te pānuiArc flash boundary at a motor control centreArcing current, incident energy and arc flash boundary for a 400 V MCC at 25 kA with a 0.1 s clearing time, and why the equipment type moves the result.
- 4 meneti te pānuiSwitchboard fault rating at 25 kA for 1 sA 1 second withstand check at 25 kA on 185 mm² copper XLPE, returning a 174.83 mm² minimum size and a 26.46 kA withstand, with a thin margin explained.
- 3 meneti te pānuiDC isolator rating for a 10 kW solar arrayRate the d.c. isolator and size the frame earth for a four-string domestic array. Check one data sheet that passes and one that fails per pole.
- 3 meneti te pānuiSolar string sizing for a 600 V inverterHow many 49.5 V modules fit a string on a 600 V inverter at -5 °C? Work cold Voc, hot Vmp, the string current, fuses and the d.c. isolator by AS/NZS 5033.
- 3 meneti te pānuiStarting a loaded conveyorA 22 kW conveyor that needs 120 % torque to break away. Why star-delta and a soft starter will not start it, and what a drive or autotransformer does.
- 4 meneti te pānuiMotor circuit for a 15 kW pump: DOL or star-deltaSize a 15 kW 400 V pump circuit: cable, breaker, contactor and overload relay. Compare DOL, star-delta, soft starter and drive starts.
- 3 meneti te pānuiTransformer secondary fault current for 500 kVAA 500 kVA 11 kV to 400 V transformer at 6 percent impedance, worked through to 721.69 A of secondary full load current and 12,028.13 A of fault current.
- 3 meneti te pānuiFactory power factor correction: 250 kW at 0.78A 250 kW factory load at 0.78 power factor lifted to 0.95. The kvar, the capacitor steps, the current saved, the kVA released and why the bank is detuned.
- 3 meneti te pānuiFault level at a sub‑board, 300 kVA transformerWork the prospective fault current at a sub-board 45 m from a 300 kVA transformer, three-phase and phase-earth, and check 6 kA and 10 kA breakers against it.
- 4 meneti te pānuiAmpSize vs jCalc vs free cable sizing toolsCompare AmpSize with jCalc and other free cable sizing tools. One 63 A three-phase submain shows which checks decide a size, and what AmpSize leaves out.
- 3 meneti te pānuiArc flash incident energy at a 400 V switchboardA 400 V board with 20 kA bolted fault and 0.2 s clearing gives 6.23 cal/cm² at 455 mm, an arcing current of 9.64 kA and a 1395.97 mm boundary.
- 4 meneti te pānuiAS/NZS 3008.1.2 Table 52: the k factorWhat Table 52 governs, how the adiabatic check uses k, and a 10 kA fault cleared in 0.1 s that needs 22.11 mm² against an installed 25 mm² conductor.
- 3 meneti te pānuiIDMT curve grading for a 100 A feederTwo standard inverse relays at 2000 A give a feeder trip at 0.23 s, an incomer trip at 0.99 s and a grading margin of 0.76 s, read off one chart.
- 6 meneti te pānuiAS/NZS 3008.1.1 table numbers: 2017 to 2025Each AS/NZS 3008.1.1 table AmpSize reads, with its 2017 number, its 2025 number and whether its values moved, and one submain that cites both sets.
- 4 meneti te pānuiAS/NZS 3008.1.1 vs 3008.1.2: AU and NZ conditionsThe AU part of AS/NZS 3008.1 rates cable at 40 °C air and the NZ part at 30 °C. One 32 A circuit needs 6 mm² in Australia and 4 mm² in New Zealand.
- 5 meneti te pānuiAS/NZS 3008 vs BS 7671: cable sizing comparedHow BS 7671 and AS/NZS 3000 with AS/NZS 3008.1 size a cable, where they differ, and why a BS current rating never converts into an AS/NZS one.
- 5 meneti te pānuiDC cable size: 48 V battery and 600 V PV arrayTwo d.c. circuits sized to AS/NZS 3008.1.1:2025, a 48 V battery-to-inverter run that current sizes and a 600 V array feed that voltage drop sizes.
- 3 meneti te pānuiProspective fault current at a main switchboardA 16 kA fault cleared in 0.1 s on 70 mm² copper XLPE, with the minimum conductor size, the withstand current and the k factor the adiabatic check returns.
- 5 meneti te pānuiAS/NZS 3008.1.1:2025: what changed from 2017The 2025 AU part adds d.c. ratings to 1500 V, renumbers every table and moves some ratings. Four circuits, each run on both editions, show what moves.
- 3 meneti te pānuiVoltage rise for a 5 kW solar inverter cableA 5 kW single-phase inverter 40 m from the switchboard on 10 mm² copper, with the rise in volts, the percent and the maximum length the tool returns.
- 4 meneti te pānuiEarth fault loop impedance and maximum ZsWhat earth fault loop impedance measures, how the maximum Zs check works, and a 32 A circuit on 6 mm² over 25 m that lands on 0.67 ohms against a 0.96 limit.
- 3 meneti te pānuiVoltage drop with the mV/A·m methodHow the millivolt per amp metre method works, with a 32 A run over 25 metres on 6 mm² copper and the exact drop, percent and maximum length the tool returns.
Ngā tātaitai e whakamahia ana e ēnei aratohu
- Arotake Obtrusive LightTirohia te rama o waho i tētahi matapihi rohe e ai ki AS/NZS 4282.
- Tātaitai iahiko generatorTe iahiko uta katoa me te iahiko hapa o tētahi generator mai i tōna kVA.
- Tātaitai Arc FlashTātaungia te pūngao o tētahi arc flash me tōna karaehe PPE.
- Arc flash me te karaehe pākahikoDVC pākahiko, karaehe mōrearea, pūngao arc flash me te taumata PPE.
- Tātaitai IDMT gradingWhakatakotoria ngā kōpiko tuku o ngā relay overcurrent wā-whakahuri.
- Tātaitai fault rating tauraTirohia mēnā ka ū tētahi kaikawe ki te iahiko hapa.
- Tātaitai PV isolator me te whakawhenuaWhakatauhia ngā taura PV array, te d.c. isolator me te whakawhenua.
- Tātaitai PV stringNgā module ia string, te iahiko string me te isolator mō te PV.
- Whakataurite tikanga tīmatanga mōtāWhakatairitea ngā tīmatanga DOL, star-delta, soft start me te drive.
- Tātaitai ara iahiko mōtāTaura, breaker, contactor me te overload mō tētahi mōtā.
- Tātaitai TransformerTātaitia te iahiko uta katoa me te impedance o te transformer.
- Tātaitai power factor correctionKimihia te kvar o te capacitor hei whakapiki i tētahi power factor.
- Tātaitai taumata hapaTe iahiko hapa ka puta pea i tētahi papa mai i tōna puna.
- Tātaitai rahi tauraKimihia te rahi taura iti rawa e pass ana i ia arotake.
- Tātaitai rahi taura DCWhakaritea te rahi o tētahi taura d.c. tae atu ki te 1500 V mō te iahiko me te heke voltage.
- Tātaitai Piki VoltageTātaitia te piki voltage mō te whakatipu hiko kua whakaurua, mō te PV rānei.
- Tātaitai earth fault loop impedanceTirohia te earth fault loop impedance ki te Zs nui rawa.
- Tātaitai heke voltageTātaitia te heke voltage i tētahi ara taura, ā, tirohia te rohe.