Maximum Demand Calculator
Calculate residential maximum demand using AS/NZS 3000 diversity factors. Enter your loads and get an itemised breakdown with total demand in kVA and Amps.
For reference only — always verify with the current published AS/NZS 3000:2018 standard. This calculator implements Table C1 Column 2 (single domestic installation).
Domestic Load Inputs
AS/NZS 3000:2018 Table C1, Column 2
Includes exhaust fans ≤150W, ceiling fans ≤150W
Number of individual 10A outlets (not circuits)
Range, oven, cooktop — total rating in watts
Fixed space heating or cooling >10A. Use the greater if both.
Full-load current in amps
About This Maximum Demand Calculator
This calculator works out the maximum demand for a residential installation using the diversity rules from AS/NZS 3000. Built for Australian electricians doing switchboard upgrades, new builds, or supply assessments.
Use it when you need to size a main switch, consumer mains, or submit a load schedule to the distributor. Enter each load group and get an itemised breakdown with the total in amps and kVA.
Diversity factors follow AS/NZS 3000 Appendix C, Table C1 Column 2. This is a reference tool. Always verify against the current edition of the standard for your specific installation.
Related Tools
Need switchboard labels for your next job? Design and order custom engraved labels online — from $1 ex GST.