Electrician glossary

Short, plain-English definitions of the terms you'll meet when choosing a electrician provider in Malaysia.

What are inverter aircon wiring requirements?: Inverter aircon wiring requirements are the electrical specifications for circuit protection, conductor sizing, and isolation needed to safely supply inverter-type air conditioning units, which draw variable power and generate harmonic frequencies different from fixed-speed models.
What is a busbar?: A busbar is a metal strip or conductor used to distribute electrical current from a main power source to multiple circuits or loads within a switchboard or electrical panel.
What is a chargeman in Malaysia's electrical industry?: A chargeman is an ST-certified senior electrician who operates, maintains, and supervises high voltage electrical installations in commercial and industrial facilities in Malaysia.
What is a competent person (electrical)?: A competent person in electrical work is someone certified under Malaysian electrical regulations to safely design, install, maintain, test, and supervise electrical installations and systems.
What is a consumer unit (DB box)?: A consumer unit (DB box) is the main distribution panel in a building where incoming electricity is divided into separate circuits, each protected by a breaker or fuse for safety and control.
What is a miniature circuit breaker (MCB)?: A miniature circuit breaker is an automatic safety switch installed in a consumer unit that trips to disconnect power when it detects an electrical overload or short circuit, protecting the circuit and connected equipment from damage.
What is a residual current device (RCD/ELCB)?: A residual current device (RCD) or earth leakage circuit breaker (ELCB) is an electrical safety switch that automatically disconnects power when it detects current leakage to ground, preventing electric shock hazards.
What is a single line diagram (SLD)?: A single line diagram is a simplified schematic representation of an electrical power distribution system that shows how power flows from the main source through transformers, switchgear, and circuits to individual loads in a building.
What is a solar inverter?: A solar inverter is an electrical device that converts the direct current (DC) electricity generated by solar panels into alternating current (AC) electricity that household appliances and grid systems can use.
What is a wireman (Kabel Elektrik)?: A wireman (Kabel Elektrik) is an ST-certified electrical worker in Malaysia qualified to install wiring systems, either under supervision or independently depending on the project scope.
What is a wiring diagram?: A wiring diagram is a technical drawing that maps how electrical circuits, switches, outlets and components are connected and function together in a building or installation.
What is an isolator switch?: An isolator switch is a dedicated electrical switch installed at or near an appliance (such as an air conditioning compressor) to safely disconnect power for maintenance and emergency purposes.
What is cable size / wire gauge (mm²)?: Cable size, expressed in square millimetres (mm²), refers to the cross-sectional area of an electrical conductor and determines how much current it can safely carry.
What is earthing and grounding?: Earthing (or grounding) is a safety connection that routes electrical fault current safely into the earth or ground, preventing electric shock and protecting equipment from damage.
What is kilowatt-peak (kWp)?: Kilowatt-peak (kWp) is the maximum power output a solar panel system can generate under standard test conditions of 1000 watts per square meter of sunlight intensity and 25 degrees Celsius cell temperature.
What is load calculation?: Load calculation is the process of determining the total electrical demand a building requires, used to correctly size wiring, circuit breakers, and electrical supply.
What is net energy metering (NEM)?: Net energy metering (NEM) is the Malaysian government scheme that credits solar panel owners for excess electricity they export to the TNB grid, offsetting their own consumption charges on a monthly basis.
What is Perakuan Kompetensi (PC)?: Perakuan Kompetensi (PC) is the official competency certificate issued by Suruhanjaya Tenaga (ST) to electrical workers who have demonstrated the knowledge and practical skills needed to safely carry out wiring work in Malaysia.
What is PVC conduit and trunking?: PVC conduit and trunking are plastic pipes and channels that enclose and protect electrical cables and wiring in buildings, used in both concealed wall installations and surface-mounted applications.
What is R32 refrigerant?: R32 is a hydrofluoroolefin (HFO) refrigerant gas used in modern split-unit air conditioning systems, classified as mildly flammable and requiring stricter installation safety protocols than older non-flammable refrigerants.
What is SEDA Malaysia?: SEDA Malaysia is the government authority responsible for administering renewable energy programs, net energy metering (NEM) schemes, and licensing solar installation businesses across Malaysia.
What is single phase vs three phase electrical supply?: Single phase is a two-wire electrical supply for household and light commercial loads, while three phase is a three-wire system delivering power more efficiently to factories, heavy machinery, and industrial air conditioning systems.
What is Suruhanjaya Tenaga (ST)?: Suruhanjaya Tenaga (ST) is Malaysia's statutory body responsible for regulating electricity supply, licensing electricians, and enforcing electrical safety standards across the country.
What is TNB supply authority?: TNB supply authority is the regulatory and operational framework by which Tenaga Nasional Berhad (TNB), Malaysia's main electricity utility, governs new electrical supply connections, meter installations, and load capacity upgrades for residential and commercial properties.