This acknowledges that not every appliance runs at the same time. You don't run your air conditioning, oven, hot water system, and every light in the house all at once for hours on end. The Wiring Rules allows us to apply to account for this intermittency.
If you are an electrical apprentice, a contractor, or an engineer in Australia or New Zealand, the term "Maximum Demand" is one you will encounter constantly. It is the cornerstone of safe and efficient electrical installation design. as3000 maximum demand
In practice, determining MD is not a one-step calculation; it is an iterative design loop: This acknowledges that not every appliance runs at