Back to Basics – Electrical Boot Camp
Part 1: Back to Basics Series
It’s time to review the elements of electricity and the electrical distribution systems so that you know absolutely what you must do to protect yourself, your co-workers, the public and your family. There are many important things we need to go over, but in this series I’ll keep the sections in each issue short so that you can memorize them or get tattoos of the best parts to refer to. There will be a test—using this information every day to stay safe!
Electricity is always trying to go to ground, or zero volts. That’s what makes electrical things work—the electricity going from a higher voltage to a lower voltage. 120 volts at the plug (Hot), going through a motor to get to the zero-volts side of the motor (Neutral), going to ground.
Electricity will always take the path of least resistance to flow from high to low voltage. Anything that will conduct electricity is called a conductor, and some are lower resistance than others, like copper. The perfect conductor for electricity is water mixed with a little salt and chemicals. Since the human body is 80+% water, salt and chemicals, anytime there is damage in a wire, tool, cord, etc. where the electricity has options, it will always choose you over any other conductor to flow through. (Not to be gross, but if you’ve ever tasted your blood, cut-finger time, did you notice it’s slightly salty tasting? You vampire you!)
The moral of the story: If you give electricity a choice between using you or any other conductor to flow from high to low voltage, it will always choose you and it will always be a very bad for you—from heart-stopping shock to internal organs being severely damaged. Your blood is the conductor, and the blood vessels are the wires the electricity is going to use to travel through your body causing serious damages/burns.
Home electrical systems that are typically 120/240 volts, 100–200 amps, called Secondary voltages, kill more people than encountering the 4,800–23,000 volts, thousands of amps, called Primary voltages. Primary-carrying conductors are normally 40–45 feet off the ground at the top of the pole and tough for you to get close to, unless you are in a bucket truck or freakishly tall. But the secondaries are only 12 feet off the ground coming to your weatherhead, and please trust me when I say, secondaries are NOT insulated wire. They may have been the day they were installed fresh out of the box, but don’t trust them with your life. Let a qualified electrician or your utility mess with your secondaries. You can supervise from the ground.
Do you need to do some work near the secondaries or around your weatherhead? Call your utility and ask them to install some insulation from the weatherhead out 10–12 feet or more if you need it. (It’s a FREE service.) Utilities will not trim tree limbs off the secondaries between your house and the street. You will need a qualified tree crew, but ask the utility to shut the power off during the time you schedule for the tree work.
As a utility safety person, I sadly had two occasions to investigate tree people who died while trimming limbs around secondaries. One contacted the energized secondaries with his aluminum pruning tool, and the other, working in uninsulated bucket truck, cut a limb which became hung up on primaries and then grabbed the limb with his bare hand. Very sad…because both were so easily preventable.
Guess which job had an ambulance carry away the shocked worker?
This gentleman did not pay attention to last month’s article!! Should we be concerned the life insurance beneficiary took time to snap the picture before rushing out to stop him?