Topic 04: The Past Electrical Environment

Now that you’ve learned the difference between linear and non-linear loads, the different types of linear loads and that essentially all loads in the past were linear loads, now let’s focus on what the electrical environment of the past looked like. What do we mean by the “what the electrical environment used to look like”? Here’s some important points that describe this. When describing this, we’ll start from the far outside and work our way towards the linear loads, since they were the most common types of loads prior to the 1970’s. The electrical environment surrounding an electrical load (linear and non-linear) includes everything around it.

• Solar system – The Earth is in orbit around the Sun. The Earth is not always the same distance from the Sun because its tilt changes as it orbits the Sun. This is what causes the four seasons. Because the tilt of the Earth changes, the distance from any one point tangential (90° to the Earth’s surface) to the Earth’s surface changes as the Earth orbits the Sun.