Electrical Terms & Definitions
A plain-English guide to electrical terms, certificates and compliance requirements in Victoria. Whether you're a strata manager navigating a defect notice or a homeowner planning an upgrade — we've got the jargon sorted.
- COES(Certificate of Electrical Safety)
- A legal document issued by a licensed electrician confirming that electrical work meets AS/NZS 3000 wiring rules and the Electricity Safety Act 1998. Required for both prescribed and non-prescribed electrical work. The certificate is lodged with Energy Safe Victoria, and you must receive a customer copy within 30 days of the work.
- Defect Notice
- A notice issued by your electricity distributor when your property's electrical installation is found to be unsafe or non-compliant. The defect may have been identified during a routine meter read, after a storm, or when a fault is reported. A defect notice may result in your electricity supply being disconnected until a licensed electrician rectifies the defect and issues a COES.
- DNSP(Distribution Network Service Provider)
- The electricity distributor for your area — aka Supply Authority. The company that owns and operates the poles, wires, underground cables and electricity meters. In Victoria the five DNSPs are CitiPower, Powercor, Jemena, United Energy and AusNet Services. We handle the entire DNSP / Supply Authority process on your behalf — from initial liaison and paperwork through to coordination and reconnection. Mains upgrades, meter panel changes, defect notices — we take care of it all.
- ESV(Energy Safe Victoria)
- The independent regulatory authority for electrical and gas safety in Victoria. ESV issues licences to electricians and electrical contractors, investigates electrical incidents, maintains the register of Registered Electrical Contractors (RECs) and oversees compliance with the Electricity Safety Act 1998.
- GMP(General Metering Panel)
- The panel that houses your building's electricity meters. The GMP is the distributor's point of connection to your premises — it's where the supply from the network meets your internal electrical installation. The GMP must meet the DNSP's specifications for meter installation and access.
- REC(Registered Electrical Contractor)
- An ESV-registered business authorised to carry out electrical installation work in Victoria. All licensed electricians must be employed by or subcontracted to an REC. E J Lack Electrical operates under REC licence 1827.
- RCD(Residual Current Device)
- A safety device (commonly called a safety switch) that cuts power within 30 milliseconds if it detects current leaking to earth — preventing electric shock. RCDs are a critical component of modern switchboards and are required on most circuits under the Australian Wiring Rules (AS/NZS 3000).
- RCBO
- A combined unit that merges an MCB (circuit breaker) and an RCD (residual current device) into one device. RCBOs provide individual circuit protection with residual current detection — meaning only the affected circuit trips rather than the entire board. Best practice for modern switchboards.
- Soft Wiring
- A modular, plug-and-play power and data distribution system for commercial workstations. Uses pre-terminated connectors certified to AS/NZS 61535.1 that can be reconfigured without an electrician. The system includes floor boxes, umbilicals, power rails, in-desk modules and cable management. Ideal for office fit-outs where flexibility and clean installs matter.
- Type A Safety Switch
- A safety switch that detects both AC and pulsating DC residual currents. Mandatory for new installations in Victoria since 30 April 2023 under AS/NZS 3000:2018 Amendment 2. Required where solar inverters, EV chargers, LED drivers or variable speed drives are present, as these can produce pulsating DC fault currents that older Type AC switches cannot detect.
- VSIR(Victorian Service and Installation Rules)
- The rules governing how electrical installations connect to the distributor's network in Victoria. The 2025 edition of VSIR became mandatory from 1 January 2026. These rules cover everything from earthing and bonding to meter panel requirements and point of attachment specifications.
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