Cert III Electrician key terms

The ranked order of risk controls from most to least effective: eliminate the hazard, substitute it, use engineering controls, apply administrative controls, then use personal protective equipment as the last line of defence.

A structured process of identifying hazards, judging how likely and how severe any harm could be, and deciding what controls are needed before work starts.

Clothing and gear worn by a worker, such as insulated gloves, safety glasses, hearing protection and arc-rated clothing, that reduces exposure to hazards but does not remove them.

The procedure of disconnecting all supply sources, proving the circuit dead, and fitting personal locks and danger tags so the installation cannot be re-energised while work proceeds.

Attaching a clearly written danger tag to an isolation point or control device to warn others that equipment must not be operated until the person who fitted the tag removes it.

A safe working habit of verifying an installation or conductor is de-energised with a proven tester immediately before any contact, never relying on assumptions or labels alone.

A written document describing how a high-risk construction task will be carried out, listing the hazards, the controls, and the sequence of steps workers must follow.

A sudden release of intense heat, light and pressure caused by an electrical fault through air between energised conductors, capable of causing severe burns and blast injury.

The legal obligation of a person conducting a business or undertaking, and of each worker, to take reasonable steps to protect health and safety so far as is reasonably practicable.

A serious workplace event, such as a death, serious injury or dangerous electrical incident, that the regulator must be told about immediately after the site is made safe.

Sorting waste such as copper cable offcuts, fluorescent tubes, batteries, packaging and general rubbish into separate streams so each can be recycled or disposed of correctly.

The responsibility to prevent pollution and minimise harm to land, water and air from work activities, including correct handling and disposal of waste and hazardous substances.

The relationship stating that voltage equals current multiplied by resistance, so any one value can be calculated when the other two are known in a circuit.

A circuit where components are connected end to end so the same current flows through each, while the supply voltage divides across the individual resistances.

A circuit where components are connected across the same two points, so each receives the full supply voltage while the total current divides between the branches.

The relationship that electrical power in watts equals voltage multiplied by current, and also equals current squared multiplied by resistance.

The ratio of real power to apparent power in an alternating current circuit, indicating how much of the supplied current performs useful work rather than building magnetic fields.

An electric current that reverses direction periodically, typically many times each second, as supplied by the mains distribution network.

An electric current that flows continuously in one direction, as produced by batteries, solar panels and rectifier circuits.

The effective value of an alternating quantity, equal to the direct value that would produce the same heating effect; for a sine wave it is the peak divided by about 1.414.

A test instrument combining voltage, current, resistance and often continuity measurement functions, selected by a rotary dial and connected to the circuit with test leads.

A testing sequence in which the instrument is checked on a known source before and after the actual test, confirming the tester worked and the reading can be trusted.

The reduction in voltage along a circuit caused by current flowing through conductor resistance, which must be limited so connected equipment receives adequate voltage.

The maximum continuous current a cable can carry under stated installation conditions without its insulation exceeding its rated temperature.

A multiplier below one applied to a cable's tabulated current rating to account for conditions such as grouping, ambient temperature, thermal insulation or installation method.

Selecting and setting circuit breakers and fuses so that the device nearest a fault operates first, protecting the cable while limiting disruption to the rest of the installation.

A protective switch that compares current in the active and neutral conductors and trips when a small difference indicates leakage to earth, reducing electric shock risk.

Connecting exposed conductive parts and the installation's earth system together and to the general mass of earth so fault current has a low-impedance path that operates protection.

Joining conductive parts such as metal pipes, frames and earth bars so they sit at substantially the same potential, preventing dangerous voltage differences between them.

A test applying a raised direct voltage between conductors and earth to measure insulation resistance and confirm the wiring is sound and dry before energising.

A low-resistance check confirming that a conductor or protective earthing path is unbroken end to end, usually performed with a low-voltage ohmmeter.

A drawing using standard symbols to show the electrical supply, switchboards, protective devices and circuits of an installation in simplified form.

A drawing updated after construction to record the installation exactly as it was built, including any variations from the original design.

A table fixed at a switchboard listing each circuit, its rating, protective device, cable size and the equipment it supplies, supporting safe isolation and future work.

An alternating current motor in which a rotating magnetic field from the stator induces currents in the rotor, producing torque without brushes or direct electrical connection to the rotor.

A motor starting method that connects the motor directly to full supply voltage through a contactor, giving high starting current and simple control.

A protection device that trips a motor control circuit when sustained excess current heats a sensing element beyond a set level, preventing motor winding damage.

Choosing equipment, lighting and control strategies that deliver the required service using less energy, lowering running costs and greenhouse gas emissions over the installation's life.

Techniques such as load scheduling, power factor correction and automatic control that reduce peak demand and total consumption from the supply network.

Selecting materials and equipment on whole-of-life criteria including energy use, durability, recyclability and responsible sourcing, not just purchase price.