How Does Grounding Work?

A basic question about electricity is “how does grounding work?”  Here’s a short (no pun intended) explanation.Installing Ceiling Light

The purpose of “grounding” is to allow the electrical current an easy path to return to the service panel in the case of a short circuit.  The service panel is where the incoming electrical current is distributed to individual circuits.   Sometimes an easy path isn’t available when a short-circuit or over-current occurs.  That allows the electrical energy to go through you and ruin your whole day with a big shock.

In the circuits, electrical power flows from the panel around the house going to various outlets and devices.  The hot wire (red or black) provides the supply path for the energy.  The neutral wire (white) provides the return path. And the ground wire (green or bare copper) provides a backup safety path to reduce the danger from a short circuit or from over current.   When a problem occurs, the current is able to use the ground wire to get back to the circuit breaker and trip it.  That causes the supply to stop immediately and the circuit is no longer live and dangerous.

In many homes and offices, there are un-grounded appliances, such as small fans and toasters, with only 2 prongs on the power plug.   In some homes and offices, there are also un-grounded outlets.  They only have 2 openings for power plugs instead of 3.   Whenever you are using an un-grounded appliance or outlet, there is no wired path to the ground.  If a short occurs and you are touching that appliance, you stand a good chance of being shocked.  Possibly even fatally electrocuted.   So whenever you see an un-grounded situation, remember to be careful.

A safely grounded building has all of the electrical system circuits, panels, and metal water pipe system connected.  The connection will go to a metal grounding rod driven into the earth, or sometimes buried in the earth.   Since the earth is able to absorb any amount of dangerous current, the grounding rod protects people from shocks and makes our homes and offices safe.

If you have any questions about electrical safety, give us a call.  We’ll be glad to help.

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