When I talk to clients, I often find that they will be quit a bit concerned about grounding. I imagine we are all indoctrinated to believe that grounding is very important to safety, which is good, because it is important to safety. However, I find it amusing that people might really be concerned about it but not really know what it does, what its function is.
I think if you asked most people who thought they knew what grounding was, they would say that it dumps electricity into the ground instead of starting a fire or electrocuting you. If you said it in a more proper way, it would go like this, grounding provides a path of low resistance for the electricity to flow to. Electricity always follows the path of least resistance, so if it comes in contact with something that is grounded then the electricity will flow to the ground.
That concept in and of itself is a little vague and often misunderstood. It is okay not to understand the concept of grounding, in the 1993 National Electrical Code, there were factual errors in describing why something must be grounded, and this code is written by scientists, engineers, and people from the field with lots of experience.
Here is an explanation of what grounding is most commonly used for and what it does. If you have an outlet and the device and the box it is attached to is grounded, then any stray current will go to ground, but we are not just talking a little trickle, we are talking, in just a few cycles, suddenly your little wires are drawing 10,000 amps of current. A grounded box will cause a short circuit when it draws electricity to ground and it makes a little flash that will melt any metal because it is hotter than the surface temperature of the sun. In effect, when you ground something, you are ensuring that if anything goes wrong, a very severe lightning bolt is going to go through your house.
Now that doesn’t sound safe at all. It certainly doesn’t to me, the reason why it is done for “safety” reasons, is because all that current is most certainly going to trip the breaker, and cause the circuit to go dead. So instead of the ground fault making your box heat up and start a fire, or electrocuting anyone, it is like an instantaneous loud siren that goes off for a split second and trips the breaker.
What if the breaker didn’t work? Well, as you can imagine it is pretty important for it to work, because it will vaporize everything in the circuit and perhaps cause all sorts of untold damage.
Still we always want to make sure everything is grounded, because breakers do work and stray current will kill the power and that is the object of the game.
