Hey guys, I wrote this in response to something I read earlier. It wasn’t actually a report, but I wanted to keep it simple.
What do you think?
As a home inspector, I have to constantly improve my understanding of the interdependent systems that make up a home. I invest a lot of time digesting articles, books, and other informative resources to ensure that the quality of my inspections is above par.
The electrical system is one of the harder systems for inspectors to understand. This was again evident as I read another inspector’s report. In the electrical section, it read: “Most of the home is not on a grounded system,” continued with, “Only the kitchen and the master bath had a grounded system,” and ended with “The home’s [electrical] system is not working properly.” The inspector was referring to the outlets not having the “ground” wires installed.
Let’s work backwards and get something out the way first. The electrical system does not need the “ground wires” to work properly. During normal operation with a properly functioning system, the “ground wires” do not carry any current. The proper term for what most people commonly describe as a “ground wire” is an equipment grounding conductor (EGC). EGCs bond non-current-carrying equipment, such as metal conduit, junction boxes, and outlet/switch boxes, to the service panel, and the neutrals and EGC’s within the panel. In the event that a “hot wire” comes into contact with equipment, the EGC will allow enough current to flow back to the panel and trip the breaker (or blow the fuse). If the EGC was not there and a person came in contact with the equipment, and was also in contact with the ground, s/he could complete the circuit and receive the flow.
Notice that the EGC is not connected to the ground at all. It is, however, bonded to the grounding electrode system, which brings us to my next point.
You generally cannot have half the home or only a few circuits on a grounded system. The grounding system is designed to protect your electrical system and home in the event of a lightning strike, line surge, or other electrical event. The neutral is grounded at the transformer and then again at your service panel. The grounding system creates a low-resistance path to the ground so that excessive voltage can dissipate away from the house. A structure has one ground system. The assertion that “most of the home is not on a grounded system” does not really make any sense.
Lastly, the correction for “ungrounded” three-prong receptacles is quite simple. The NEC allows these circuits to be upgraded with GFCI protection. In other words, a three-prong receptacle with an “open ground” that is GFCI-protected is acceptable, per the NEC.