What does the term "demand factor" refer to in load calculations?

The term "demand factor" refers to the ratio of the actual load to the total connected load. This concept is critical in load calculations because it helps to determine how much of the total connected load is likely to be used at any given time. The demand factor takes into account that not all connected loads will be operating simultaneously at their maximum capacity. By assessing this ratio, engineers can design electrical systems more efficiently, ensuring that the infrastructure can handle real-world usage without being oversized or undersized.

For instance, if you have a building with multiple electrical devices that, when summed, have a large total connected load, the demand factor allows you to acknowledge that during peak times, only a portion of those devices will be in use. As such, using the demand factor enables accurate calculations of electrical service needs, which can lead to cost savings and increases in system reliability.