Electrician Handbook

Electrician's Handbook — electrical wiring diagrams, theory and calculators for electricians, students and installers.

Theory, diagrams and calculators work offline. No ads. No subscriptions.

— Theory

A variety of topics in electrical engineering: from basic concepts to grounding and lighting diagrams. Some topics include exercises with answers for self-check.

— Diagrams

Interactive electrical diagrams. You can interact with elements to better understand how they work.

— Calculators

A section with calculators, formulas, and useful reference tables.

— Tests

Built-in tests to check your knowledge.

— Contents of the "Theory" section:

Basic concepts

• Voltage, current, resistance, power

• Ohm’s Law, Kirchhoff’s rules

• Parallel and series connections

• Short circuits, safety precautions

• Electrical engineering terms

Electromechanical converters

• Transformer, generator, electric motor

• Connecting a three-phase motor using a capacitor

Protection and automation devices

• Circuit breaker, RCD, RCBO

• Voltage monitoring relay, contactor, fuses

• Surge protection devices

Cables and wires

• Wire connection methods

• Selecting cross-section by current and power

• Color coding

• Electrical panel

Power stations and substations

• Nuclear, thermal, solar, hydro, wind, and geothermal power stations

Measuring instruments

• Voltmeter, ammeter, ohmmeter, multimeter

• Clamp meter

• Electricity meter

Grounding

• Types of grounding systems

• Equipotential bonding system

Lighting

• Incandescent, LED, and other types of lamps

• Lamp holders, bases, lumens, lux

• Color temperature

• LED strip

Work execution

• Socket repair

• Installation of flush-mounted and surface-mounted sockets

• Switch installation

Additional information

• Power supply categories

• Surge overvoltages

• IP protection rating

• Electrician’s tools

• Types of outlets and plugs, voltages in different countries

• Joule’s Law, Coulomb’s Law

• Right-hand and left-hand rules

— Contents of the "Diagrams" section:

• Switch (1 and 2 gang)

• Three-gang switch

• Two-way switch

• Two-way switch with intermediate switch

• Outlets and switch in one block

• Lighting with dimmer

• Motion sensor lighting

• Relay with light sensor

• Lighting with impulse relay

• Fluorescent lamp wiring

• Socket wiring diagrams

• Magnetic starter for motor

• Star and delta motor connection

— Contents of the "Calculators" section:

• Basic formula calculator

• Electricity cost calculator

• SI unit system and metric prefixes

• Diameter ↔ cross-section table

• AWG to mm and mm to AWG conversion

• Electronic component symbols