It is useful for New Jersey home inspectors to understand how electrical grounding systems works and is installed. Electrical grounding systems direct dangerous electrical flow by providing a path between a buildings service panel and the ground. Static electricity and lighting strikes are the most damaging charges that can be dissipated. Grounding electrodes are tied into the buildings electrical system through ground wires. There are certain requirements for grounding electrodes and ground wires.
The most common problems that ground rods dissipate high voltage surges caused by lightning strikes to powerlines. Proper and correct grounding provides safety and stability to the electrical system in the home and reduces the destructive impact of these surges. If the service wire to the home is damaged proper grounding is necessary to help minimize damage. If voltage in the home is uneven or distorted there may be damage to appliances and electronic devices.
One metal that should not be used in ground wires is aluminum especially if the aluminum wires are not insulated. Aluminum wires that are unprotected are subject to corrosion and thus should not be used as ground wires or grounding electrodes. Aluminum is also a poor conductor of electricity then copper. Ground conductors are not insulated so they should not be used in this fashion. If more than one electrode is present, they have to be tied together with a binding wire across the two electrodes.
The most prevalent type of ground rod (grounding electrode) is a metal rod that is driven into the ground so that its entire length is below the level of the soil. A driven ground rod should be at least 8 feet deep into the soil. Electrical contractors sometimes trim or cut the rod short because driving it its full length is challenging. As a NJ home inspector one of the issues that I come across is a ground rod that is too short or improperly installed. Having a ground rod that is cut short is a safety hazard. What I try to do is to move the ground rod back and forth. If a rod is driven properly, it will not move. If the ground rod is too short, it will move back and forth easily. Another way to identify a rod that is too short is to look for rust at the very top. Ground rods have been coated so they do not rust. If you see rusting, then it is likely the rod has been cut too short and does not meet the eight-foot requirement.
NJ Home inspectors should also check the condition of the clamp that ties the ground wire to the ground rod. Clamps should be tight and in good condition. Clamps should be made of non-corrosive metals like copper and tightly secured.
The electrical code indicates that. Electrodes that are pipe should not be smaller than 3/4 inches. The metal electrode should be covered corrosion resistant metal. Electrodes made of steel or iron should be at least 5/8 of an inch in diameter.
One of the things that New jersey home inspectors should be familiar with is UFER grounds. Ufer is the last name of the inventor of this style of grounding which originated during World War II. This type of grounding was tested when the desert setting prevented a traditional grounding rod system to be installed in bomb storage bunkers. Ufer had a theory that if the ground wires were tied into the rebar in the bomb storage bunkers the electrical surge would be dissipated by the concrete which is high conductive. This method of grounding is seen in some newer modern residential homes.
NJ Home inspectors should be familiar with the proper configuration of the grounding electrode, ground wire and grounding clamp. Inspectors should properly inspect for the presence and proper installation of these important electrical safety elements.
John Martino
LookSmart Home Inspections
NJ Home Inspectors Lic # 24GI00058700
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