Abstract The interiors of conduits in sunlight, such as those containing conductors feeding air conditioning units on rooftops, become significantly hotter than the outside air (which is always measured in the shade). Data show that these temperature differentials can easily reach 70°F, even when the conductors are electrically unloaded. Remarkably, the differentials were found to [...]
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History of Aluminum Wire Electricity is transmitted from the utility generating station to individual meters using almost exclusively aluminum wiring. In the U.S., utilities have used aluminum wire for over 100 years. It takes only one pound of aluminum to equal the current-carrying capacity of two pounds of copper. The lightweight conductors enable the utility [...]
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In some previous issues of IAEI News, articles about some of the many “hot spots” in the electrical inspection process were identified and detailed. There are a vast number of areas in the Code where the electrical inspector or building inspector has to operate out of his or her comfort zone. Qualifications of inspectors are [...]
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One of the most versatile components of an electrical raceway system is the conduit body. The National Electrical Code defines a conduit body as “A separate portion of a conduit or tubing system that provides access through a removable cover(s) to the interior of the system at a junction of two or more sections of [...]
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In the September/October 2005 issue of IAEI News, the “Perspectives on PV” article discussed making the utility connection for utility-interactive PV systems. In some of the larger residential PV systems and in many commercial PV systems, the grid connection must be made on the supply side of the service disconnect to comply with the requirements [...]
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In part nine of this series, I discussed the development of the phasor diagram, a graphical representation of voltage or current magnitude in ac circuits at any instant in time. To better understand the uses of a phasor diagram, let’s take a look at the phasor diagrams of typical utility supply voltages. Before doing so, [...]
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All of us have ideas. Have you ever wondered how a new product idea is first conceived—is nurtured in somebody’s mind—and is refined into a finished new product for use? The vast majority of new products ideas die a sudden death in the minds of the originators. A very few survive for a while and [...]
(No Ratings Yet)Both the Canadian Electrical Code (CE Code) Part I and Part III provide requirements for minimum horizontal clearances between high voltage lines and buildings, and vertical clearances between high voltage lines and grade. This article discusses the different approach taken by each. The Canadian Electrical Code, Rule 36-110 makes reference to Table 33, which provides [...]
(No Ratings Yet)Question: Smoke alarms Many hard-wired smoke alarms illustrate the interconnection of smoke alarms in their installation instructions depicting 3 wires, hot, neutral and the signal wire and indicate the signal wire can be as small as 18 AWG. Do these conductors have to be routed in the same cable or raceway or can the signal [...]
(No Ratings Yet)Question: Type NM-B nonmetallic-sheathed cable after flood Can Type NM-B nonmetallic-sheathed cable that was immersed in water during a flood be re-used?
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IAEI, as the keystone of the electrical industry, is a membership driven, non-profit association promoting electrical safety throughout the industry by providing premier education, certification of inspectors, advocacy, partnerships and expert leadership in Electrical Codes and Standards development.
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