Underground Electrical Service

Category Archives: Electrical

Underground Electrical Service

Written on March 4, 2013 by Steve in Electrical, Exterior grounds, Fire safety

When an electrical conduit develops a gap as the photo depicts below the meter box, this opening can let water inside the conduit. In this photo , apparently for some time. This is not a good situation. Any small pin holes in the covering of the electrical cables will cause deterioration, especially when the main conductors are aluminum, which is normally installed.

Also since there is a separation of the exterior protective conduit, this indicates that there is also pressure pulling the electric cables downward- that could affect the integrity of the electrical connections within the meter box. The meter box is the place where the underground cables are connected to the house. It is where an additional cable is fastened and is connected to the main service panel usually within the house garage or basement.

More often than not, when a conduit settles, as viewed in the photo, soil within the trench was insufficiently compacted during construction. The soil grade will settle normally around a house over time . That’s why one should wait a couple of years before planting shrubs or landscaping.

Often the soil settles 6 to 12 inches but is not a concern as long as the trench was properly compacted during the installation. In this case the soil must have settled about 4 inches after the underground conduit was installed, judging from the distance between the soil and he foundation paint.

As soil settles it puts pressure on the underground conduit protecting the service conductors. Eventually the pressure became too great for the connection under the meter box — you can see that the conduit completely separated, and may be still slowly pulling apart.

This situation will eventually will become a problem. The three large cables between the conduit and box are the electrical service conductors. They are carrying the electrical load to the house.

Looseness in (or damage to) the neutral service conductor can cause wild fluctuations in voltage. Anything different than what is considered normal can cause many problems. Appliances and fixtures don’t want too much or too little voltage – motors can literally burn up and light bulbs will burn out. Obviously, since the electrical connections are not visible during the home inspection, further evaluation is advised here by a reputable electrical contractor.

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Arc Fault Circuit Breakers (AFCIs)

Written on December 22, 2012 by Steve in Bathrooms, Electrical, Fire safety, Mechanical systems

An Arc Fault Circuit Interrupter (AFCI) is circuit breaker designed to prevent fires by detecting an unintended electrical arc and disconnecting the power before the arc starts a fire. An AFCI must distinguish between a harmless arc that occurs incidental to when switches are operated or snapped, plugs are disconnected from appliances, or an undesirable arc that can occur, for example, in a lamp cord that has a broken conductor in the cord.

Arc faults in a home are one of the leading causes for household fires. The National Fire Protection Agency (NFPA) estimated that in 2010, in the United States, over 40,000 fires are attributed to home electrical wiring defects. These fires resulted in over 1.5 billion dollars in property damage, in over 400 deaths and over 1,500 injuries that year.

Ordinary conventional circuit breakers only respond to overloads and short circuits. They do not protect against arcing conditions that can produce an instantaneous peak current with temperatures of several thousand degrees. The circuit breaker reads the averaged heat over the full cycle of current rather than the concentrated heat that occur at the point of the arc. Even though the arc has occurred, there will be less current drawn than is necessary to trip a conventional breaker. This is the origin of many house fires.

An AFCI is selective so that normal arcs do not cause it to trip. The AFCI circuitry continuously monitors the current and discriminates between normal and unwanted arcing conditions. Once an unwanted arcing condition is detected, the AFCI opens its internal contacts, thus de-energizing the circuit and reducing the potential for a fire to occur. An AFCI should not trip during normal arcing conditions, which can occur when a switch is opened or a plug is pulled from a receptacle.

AFCIs resemble a (GFCI) (Ground-Fault Circuit Interrupter Device) in that they both have a test button although it is important to distinguish between the two. GFCIs are designed to protect against electrical shock of a person, while AFCIs are primarily designed to protect against arcing and fire.

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Attic Access

Written on February 21, 2012 by Steve in Active Rain, Electrical, Fire safety, insulation, Mechanical systems, Plumbing, Structure

Stephen, who has been inspecting homes in Central New Jersey since 1998, says he often goes the extra mile when inspecting attics. When necessary, I have taken clothes out of the closet myself or with the help of the home owner or real estate agent. I usually put an old sheet or towel over the clothes and try to position my step ladder as best as possible so as to gain access thru the scuttle hole. If there are two access points, I can climb over to the other side and get in that part of the attic anyway.

Gaining access into the attic is always an important part of the home inspection process. There are many areas of concern, such as, plumbing venting pipes used in conjunction with bathroom exhaust and clothes dryer ducting, flue pipes that are connected to the homes heating system, fire separation walls, type and condition of installed insulation, possible animal infestation, possible mold and mildew, deficient structural conditions, attic ventilation and the possiblity roof leaks.

The most difficult problem I sometimes face is actually squeezing through the scuttle access hole itself, that can be severely undersized especially in older homes. If I didn’t go in the attic or any other space for that matter, the lack of access is documented in the report . “Photos are always a plus.”

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Aluminum Wiring

Written on February 19, 2012 by Steve in Electrical, Fire safety, Mechanical systems

ALUMINUM WIRING: Aluminum branch wiring, when used for general lighting circuits, can be hazardous because of its tendency to oxidize and its incompatibility with fittings designed for other metals used in the electrical system. Improper connections can cause electrical resistance, which may in turn cause overheating and fires. These single strand aluminum wires, used in many houses built between 1961 and 1978, are not necessarily dangerous however. As long as proper connections are used, and the connections are made without damaging the wire, aluminum wiring is considered safe.

The main factor in determining whether a system is safe is the type of outlets and switches to which the aluminum wire is connected and the workmanship of the installation. Outlets and switches which are designated CO/ALR are considered appropriate for use with aluminum wire. These markings are found at the top or bottom of fixture mounting tabs, located under the plastic wall plates. Where indications are such that this is not the case, a licensed electrician should be called in to make a further evaluation of the system and to make repairs or modifications to the aluminum wiring to insure future safety.

Warning signs of unsafe aluminum wiring include: unusually warm or warped outlet and switch cover plates, smoke or sparks coming from outlets or switches, strange odors in the area of outlets and switches, periodic flickering of lights, or untraceable problems with plug-in lights and appliances. If any of the above are ever encountered, a licensed electrician should be called in to further evaluate the problem and make repairs as needed. The use of anti-oxidant paste on all exposed portions of aluminum wiring is also recommended as a precaution.

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