Since a lot of homes in the Philippines are not grounded and there is a lot of discussion about this, we thought it would be advantageous to a lot of people to understand some of the myths surrounding grounding and electricity.
Basic rules about Current
Before we get into the myths, it is helpful to first know these rules.
- Current leaves the source and returns to the source. That is called a circuit. If you take a battery, the circuit is complete ONLY if you have one part of the circuit connected to the positive and the other side to the negative. There is NO circuit if you connect one side to the positive and the other side to ground. Try it. Take a battery and connect positive to the one terminal of the light bulb and connect the other terminal to ground. It will not go on. (Do this with a battery, not a 220v power cord!) Current is always trying to make it back to the source.
- Current does not go to Ground. You cannot expect that a circuit connected to the earth will protect you from an electrical shock. it cannot. A ground rod will not protect you from electric shocks.
- The ONLY way to prevent or stop an electric shock is to turn off the current.
Here are the Myths.
- “Grounding provides the path necessary to clear a ground fault”. This is false. IT WILL NOT TRIP THE BREAKER.
- “Current takes the path of least resistance”. This is probably the biggest myth about electricity. It does not.
- “Grounding brings everything to zero potential. This reduces touch and step voltage to a safe value”. This is absolutely not true.
- “The more grounding the better”. Absolutely false. In fact, too much grounding can cause more problems than it solves.
- “Grounding a light pole is necessary and is required by code”. We are not sure about Philippine code, but it is absolutely not true. In fact, grounding light poles have resulted in poor little male dogs getting electrocuted when the relieved themselves against the pole.
- “A generator should be grounded”. It absolutely should not be. Unfortunately, even generator manufacturers sometimes erroneously state that their device must be grounded. It is dangerous.
- “Attaching a ground device reduces the possibility of voltage on equipment in the first place”. Absolutely not true.
- “Minimizing ground resistance will i) Help trigger circuit breakers faster minimizing duration of hazard. ii) Keep voltage rise to a minimum also reducing hazard”. This is patently not true.
- “Bonding devices together so that there are multiple grounding points will lower overall resistance to ground limiting voltage rise and duration of hazard”. Not true.
- “Grounding protects against electric shock”. It does not.
The most important thing to consider when reading through this list of fallacies is to know that current MUST RETURN TO ITS SOURCE.
If you put that returning current to ground, it will still, by hook or crook, make its way back to its source.