Blog – Electrical Drafting, SLDs & Electrical Engineering Consultants
Why your project needs electrical engineering consultants and accurate electrical drafting
Every building project depends on one set of electrical drawings that everyone trusts. Builders price from them, electrical contractors install from them, and building surveyors and network distributors approve them. When those drawings are wrong, the cost shows up as variations, failed inspections and delayed handovers.
At J George Consulting, we are independent electrical engineering consultants based in Melbourne. We provide electrical drafting, single line diagrams (SLDs) and full electrical design for commercial, education, residential and industrial buildings across Victoria, New South Wales and Queensland. Our drawings are produced and checked by a chartered engineer (CPEng, NER, RPEQ, RPEV), so they are ready for construction and compliance sign-off.
What is a single line diagram (SLD)?
A single line diagram (SLD) shows a building's whole electrical distribution system on one page, using a single line for each three-phase circuit. It is the most important drawing in any electrical package, because it is the one contractors, operators and auditors refer to first.
A compliant, buildable SLD should show:
Point of supply, consumer mains and metering arrangement
Main switchboard (MSB), distribution boards (DBs) and mechanical services boards
Protective device ratings, types, trip curves and settings
Cable sizes, types, lengths and installation methods (sized to AS/NZS 3008.1.1)
Maximum demand and prospective fault levels at each board
Earthing system, MEN link and RCD protection
Generator, UPS, solar PV, battery and EV charger connections
Essential and non-essential sections, including fire and life-safety supplies
An accurate switchboard single line diagram is also needed for safe shutdowns, discrimination studies, asset registers and future upgrades. If your existing SLDs no longer match what is on site, we can survey the installation and redraw them as as-built SLD drawings.
Our electrical drafting services in Melbourne
Our electrical drafting services cover every drawing a building project needs, from concept to as-built:
Single line diagrams (SLDs) for main switchboards, distribution boards and sub-mains
Electrical layout drawings for power, lighting, data and communications
Switchboard schematics and general arrangement drawings to AS/NZS 61439
Lighting layouts backed by AGi32 lighting calculations to AS/NZS 1680
Emergency and exit lighting layouts to AS/NZS 2293
Cable schedules, maximum demand and voltage drop calculations to AS/NZS 3000 and AS/NZS 3008
Protection grading and discrimination studies using PowerCAD
As-built drawings and SLD updates for existing sites, shutdowns and asset registers
Shop drawing reviews of contractor and switchboard manufacturer drawings
We draft in AutoCAD and can work to your title block, layer and CAD standards, including university and government design standards.
Why choose J George Consulting as your electrical engineering consultants
Many drafting services only draw. As electrical engineering consultants, we design, calculate, draw and sign off, so you get one accountable engineer for the whole package.
Chartered and registered: CPEng, NER, RPEQ (Queensland) and RPEV (Victoria), so we can certify designs in VIC, QLD and NSW
Engineering-checked drafting: every SLD and layout is checked against the calculations behind it, not just drawn
Standards-based design: AS/NZS 3000 Wiring Rules, AS/NZS 3008, AS/NZS 61439, AS/NZS 1680, AS/NZS 2293 and the NCC
Proven on complex sites: including University of Melbourne switchboard upgrades, shutdowns and asset register work
Fast turnaround: a Melbourne-based engineer supported by a dedicated drafting team
Independent advice: we are not tied to any supplier or contractor, so our design serves your project
How our electrical drafting and SLD process works
Brief and site information: you send architectural plans, existing drawings or site photos, and we confirm scope and fee.
Site survey (if needed): we inspect existing switchboards and record devices, cables and ratings.
Calculations: maximum demand, cable sizing, voltage drop, fault levels and protection grading.
Drafting: SLDs, layouts and schedules drawn to your CAD standards.
Engineering review and sign-off: checked and certified by our chartered electrical engineer.
Issue for construction: PDF and DWG files, plus support during tender, shop drawings and construction.
Frequently asked questions
What is the difference between electrical drafting and electrical design? Electrical design decides what is installed: load calculations, cable sizes and protection. Electrical drafting turns that design into clear drawings. We provide both, so the drawings always match the engineering.
Do I need a single line diagram for my switchboard? Yes. AS/NZS 3000 requires circuit and distribution information to be available at switchboards, and an up-to-date SLD is essential for safe isolation, maintenance, shutdowns and future upgrades.
Can you update old or missing SLDs? Yes. We survey the existing installation and produce accurate as-built SLD drawings in AutoCAD and PDF.
Do you work outside Melbourne? Yes. We are registered in Victoria and Queensland and work on projects across VIC, NSW and QLD.
Who do you work with? Builders, electrical contractors, architects, developers, facility managers, universities and building owners.
How much do electrical drafting services cost? Fees depend on building size, number of boards and drawings, and whether design and sign-off are included. Send us your plans for a fixed-fee quote.
Get a quote for electrical drafting and SLDs
Looking for reliable electrical engineering consultants in Melbourne who can draft, design and sign off? Explore our electrical drafting & SLD services or contact us with your drawings for a fast, fixed-fee quote.
J George Consulting – independent electrical engineering consultants serving Melbourne, Victoria, New South Wales and Queensland.
