Professional electrical engineering calculations referenced to exact standard clauses. Free to use. No signup required.
Essential daily-use calculations for every electrical engineer
Cross-section selection with temperature, grouping & installation derating
IEC 60364-5-52 / NEC 310Voltage drop analysis for LV and MV cable runs
IEC 60364-5-523-phase symmetrical and asymmetrical fault analysis
IEC 60909KVA rating with derating for altitude, temperature and future load
IEC 60076-1FLC, starting current, contactor, fuse and overload relay sizing
IEC 60947 / NEC 430Current and voltage transformer accuracy class and burden
IEC 61869Advanced calculations for system design and equipment selection
Capacitor bank kVAR sizing to achieve target power factor
IEC 60831Voltage dip analysis for DOL, star-delta, VFD and soft starter
IEC 60034Average illuminance and uniformity using lumen method
EN 12464Current carrying capacity and short-circuit withstand for busbars
IEC 60865-1Battery capacity (Ah) and UPS kVA for defined backup time
IEC 62040 / IEEE 485Variable frequency drive selection with input/output cable sizing
IEC 61800-2Soft starter current rating and bypass contactor selection
IEC 60947-4-2High-value specialist calculations that command premium fees
Incident energy and hazard risk category per IEEE 1584-2018
IEEE 1584 / NFPA 70EOvercurrent relay time-current curve coordination
IEC 60255Earth conductor sizing, soil resistivity and electrode design
IEC 60364-5-54 / IEEE 80Generator kVA with derating for altitude, temperature and step loading
ISO 8528-1Passive filter design for VFD and non-linear load harmonic mitigation
IEC 61000-3-2Motor control centre and distribution panel feeder sizing
IEC 61439Lightning protection level and SPD selection for LV systems
IEC 61643-11Panel count, inverter and battery sizing for grid-tie, off-grid and hybrid
IEC 62548 / IEC 62109Power system analysis tools previously only in $30,000 software
Voltage profile and power flow for radial distribution networks
IEC 60038Motor run-up time and generator voltage dip during starting
IEC 60034-12Drag & drop single line diagram with auto-linked calculations
IEC 61082Full plant load schedule with MCC and panel breakdown
IEC 60364Complete cable schedule with auto sizing and route assignment
IEC 60227 / 60502