What is Maximum Demand in Electrical Systems?

Maximum demand is the highest level of electrical power required by a household, commercial building, or industrial site at any given time. It is not simply a sum of all connected appliances; rather, it considers Diversity Factors. Diversity assumes that not every light, socket, and air conditioner will be running at full capacity simultaneously.

How to Calculate Maximum Demand

The calculation typically involves taking the full load of certain essential circuits and applying a percentage (diversity factor) to others. For example, while lighting might be calculated at 100% of the first 66% of the load, socket outlets are often calculated at a significantly lower factor (e.g., 40%) because it is unlikely every outlet will draw maximum current at once.

Why Use a Maximum Demand Calculator?

Using a calculator ensures that your main service cables and circuit breakers are sized correctly. Undersizing leads to frequent tripping and potential fire hazards, while oversizing leads to unnecessary infrastructure costs. This tool provides a simplified breakdown based on common engineering estimates to help you plan your electrical switchboard requirements.

Frequently Asked Questions

Q: What is a Diversity Factor?
A: It is the ratio of the maximum demand of a system to the total connected load of the system. It accounts for the fact that appliances operate intermittently.

Q: Does this tool follow AS/NZS 3000?
A: This tool provides a generalized estimation. For legal compliance in specific regions like Australia or New Zealand, always consult the specific tables in the local Wiring Rules (AS/NZS 3000).