Electrical Power Engineering
Design, protect and maintain power systems: short circuit and arc flash, protection and relaying, cables, earthing, transformers, power quality, motors, backup power and renewables.
Calculators and full engineering suites for power-system design and maintenance, each built on a named standard (IEC, IEEE, NEC, BS) with the formula, assumptions and limits shown — from a single cable to a protection coordination study, a disturbance record or a transformer's ageing.
Looking for scada, iec 61850 & automation? Go to the SCADA section →
Electrical engineering suites
Time-current coordination workbench for relays, breakers, fuses and motors.
Open →LV and MV cable design and sizing, from the cable schedule to site tests.
Open →Dissolved gas analysis of transformer oil for a whole fleet.
Open →Single-line diagrams, schematics and process sketches in the browser.
Open →Electrical categories
Short Circuit & Arc Flash
IEC 60909 fault currents at every bus of a network with an auto-generated single-line diagram, IEEE 1584-2018 arc-flash studies with labels and PPE, plus quick fault-level estimates and switchgear short-circuit rating checks.
- IEC 60909 Short-Circuit Calculator
- Arc Flash Study (IEEE 1584-2018)
- Arc Flash
- Fault Current Propagation (Base kVA Method)
- Parallel Generator Fault Contribution
- Switchgear Short-Circuit Rating
Protection & Relaying
IDMT relay coordination and grading, differential and earth-fault protection, breaker/fuse sizing, and generator paralleling.
- Protection Coordination Suite (full workbench)
- IDMT Relay Coordination
- IDMT Earth Fault Relay (50N/51N)
- Transformer Differential Protection (87T)
- COMTRADE Viewer & Fault Analyser
- Distance Protection Setting Assistant
- Circuit Breaker Wear & Maintenance Analyser
Cables & Line Engineering
Cable and conductor sizing, fill and pulling calculations, and overhead/distribution line voltage regulation and losses.
- Cable Engineering Suite (full workbench)
- Cable Sizing & Voltage Drop
- MV Cable Sizing
- Conduit Fill
- Cable Tray Fill
- Cable Pulling Tension
- Control / Instrumentation Cable Sizing
Earthing, Lightning & Static Safety
Earthing grid design, lightning protection and rolling sphere method, touch voltage, and static/ESD hazard checks.
- Earthing Grid Design
- Lightning Protection
- LPS Rolling Sphere Method
- Touch Voltage from Imbalance
- Static Bonding & Grounding Check
- ESD Spark Energy Check
- Ground Resistance Calculator
Transformers, CT/VT & Condition Testing
Transformer, CT, VT and busbar sizing/rating, plus insulation resistance and polarization index condition tests.
- CT Sizing & Saturation
- VT Sizing
- Transformer Sizer
- Generator & Transformer Analysis
- Busbar & Switchgear Rating
- Insulation Resistance Checker
- Polarization Index (PI)
Power Quality, Demand & Metering
Power factor correction, harmonics, demand studies, voltage/load balance, unit conversion and tariff estimation.
- Power Factor Correction
- Harmonic Analysis
- Power Quality & Energy File Analyser
- Maximum Demand
- Voltage Unbalance & Motor Derating
- DB Panel Balancer
- kW / kVA / kVAR / Amps Converter
Motors & Drives
Motor branch-circuit sizing, motor protection, and VFD energy savings.
- Motor Calculator
- Motor Protection Sizer
- Pump/Fan VFD Energy Savings
- Motor Torque Calculator
- Motor Acceleration Time Calculator
- Soft Starter Sizing Calculator
- VFD Parameter Selection Calculator
Backup Power: Batteries, UPS & Generators
Battery sizing, UPS sizing, emergency power sequencing, genset fuel, and energy storage (BESS).
- Battery & DC System Sizing
- UPS Sizing
- Emergency Power (Genset+UPS)
- Genset Fuel Consumption & Running Cost
- Energy Storage (BESS)
- Transfer Switch Sizing
- Emergency Lighting Duration
Instrumentation & Process Controls
4-20mA loop budgets, intrinsic safety, thermocouple/RTD conversion, and fire & gas loop power.
- Engineering Sketch Studio (drawing tool)
- 4-20mA Current Loop
- Intrinsic Safety (IS) Verification
- Thermocouple & RTD
- Fire & Gas Detection Loop Budget
Solar, EV & Renewables
Solar PV string/inverter sizing and EV charge point sizing — with room to grow as more renewables tools ship.
- Solar PV Sizing
- EV Charging
- Solar Charge Controller Sizing
- Solar Panel Tilt Angle
- Inverter Sizing — Solar, Off-Grid & ILR
- Wind Turbine Power Output
Building Services & Facilities
HVAC electrical sizing, lighting design, elevators, data-center PUE, life-cycle cost, and heat management.
- HVAC Electrical Sizing
- Lighting Design
- Elevator Electrical Demand
- Elevator Energy Calculator
- Data Center PUE
- Life-Cycle Cost (LCC)
- Heat Tracing Circuit Sizing
Often needed from the SCADA section
Guides
- Short Circuit & Arc Flash Guide: IEC 60909 and IEEE 1584
How short-circuit currents are calculated, which value sizes which piece of equipment, how arc-flash incident energy follows from fault current and clearing time, and the mistakes that most often make a study wrong.
- Protection & Relaying: A Practical Guide to Coordinating Fault Protection
How overcurrent, differential and arc-flash protection actually fit together — the core theory, the standards behind it, and a sensible order to work through this category's calculators.
- Cables & Line Engineering: A Practical Guide to Conductor Sizing and Installation
Why a cable has to pass two independent checks to be correctly sized, how MV cables are sized completely differently from LV ones, and why fill and pulling-tension limits matter just as much as the electrical sizing itself.
- Earthing, Lightning & Static Safety: A Practical Guide to Ground Potential and Spark Risk
Why a low earthing resistance doesn't automatically mean a safe touch voltage, how the rolling sphere method actually works, and why bonding resistance and spark energy are two different hazards that both need checking.
- Transformers, CT/VT & Condition Testing: A Practical Guide
Why CTs and VTs behave like opposite kinds of electrical sources, how a transformer's rating changes with ambient and altitude, and what separates sizing new equipment from assessing the condition of equipment already in service.
- Power Quality, Demand & Metering: A Practical Guide
Why fixing power factor can introduce a new harmonic problem, how demand-factor sizing accounts for diversity, and why utility tariffs are the one part of this category with no universal standard behind them.
- Motors & Drives: A Practical Guide to Motor Circuits and VFD Savings
Why a motor circuit needs two genuinely different protective devices doing two different jobs, how overload relay trip class is chosen, and why default VFD energy-savings estimates are an upper bound.
- Backup Power: A Practical Guide to Batteries, UPS & Generators
Why backup power is really two different technologies covering two different timescales, how NFPA 110's Type and Class ratings describe two independent things, and why nameplate battery capacity always overstates what's actually usable.
- Instrumentation & Process Controls: A Practical Guide
Why 4-20mA loops deliberately never use zero for zero, how the intrinsic safety entity concept lets you combine certified components without a full system drawing, and why thermocouples and RTDs fail in completely different ways.
- Solar, EV & Renewables: A Practical Guide to PV Strings and Charge Points
Why a PV string has to clear three genuinely independent inverter constraints at once, and why an EV charge point's earthing system can outright disqualify a design rather than just derate it.
- Building Services & Facilities: A Practical Guide
Why this category's calculators often need a non-electrical answer — heat transfer, photometry, mechanics, or economics — before the electrical sizing question can even be asked.
Sample files
- S13_Q01_fault_P132_Q01.cfg — Disturbance record of the Q01 line fault — configuration
- S13_Q01_fault_P132_Q01.dat — Disturbance record of the Q01 line fault — data
- S13_J01_load_profile.csv — Industrial customer J01 — 30 days of 15-minute demand
- S13_33kV_PQ_week.csv — S13 33 kV busbar — one week of 10-minute PQ values
- S13_Q01_QA1_operations.csv — Breaker Q01 QA1 — operations history since 2021
- S13_T1_summer_day_load.csv — Transformer T1 — summer day load and ambient