Tax Tool

Energy

Main Fuse Load Tool

Check estimated electrical load against the capacity of your main fuse. Enter your usage and energy price for a planning estimate.

Quick math0

Use this for quick arithmetic, percentages, or to check figures while filling in the main tool, without leaving the page.

Your figures

Estimate

Approximate capacity: 9.20 kW

Main fuse
40 A
Estimated load
6.00 kW
Approximate capacity at 230 V, single-phase
9.20 kW
Load within capacity
Yes

This is a simple single-phase calculation. Three-phase capacity and fuse sizing should be assessed by an electrician.

How to use this tool

  1. Use Main Fuse Load Tool for the question described above, and check that the inputs match your records and time period.
  2. Enter main fuse (Amperage per phase.).
  3. Enter estimated load (Total load to compare with the approximate single-phase capacity.).
  4. Change main fuse, estimated load to compare scenarios, then check the units in the result.

Worked example with the prefilled values

This example shows how Main Fuse Load Tool uses its starting values. Change the calculator inputs to estimate your own situation.

Main fuse
40 A
Estimated load
6 kW

Approximate capacity: 9.20 kW

  • Main fuse40 A
  • Estimated load6.00 kW
  • Approximate capacity at 230 V, single-phase9.20 kW
  • Load within capacityYes

This is a simple single-phase calculation. Three-phase capacity and fuse sizing should be assessed by an electrician.

Formula and calculation logic

Approximate single-phase capacity (kW) = fuse rating (A) × 230 V ÷ 1,000

Capacity check = entered load ≤ approximate capacity

The displayed single-phase capacity is calculated as amperage × 230 volts, converted to kilowatts, and compared with the load you enter.

Assumptions

  • This simplified single-phase comparison does not calculate three-phase capacity, cable sizing, fuse characteristics, or installation safety. Ask an electrician to assess an installation.

Published sources

Further reading for checking current rules and information. These links are not live inputs to the tool.

Questions about this tool

Can this result tell me whether my main fuse is safe?

No. It compares an entered load with a simplified single-phase capacity. It does not assess wiring, phases, fuse behavior, or installation safety; ask an electrician to check those.