Dec 10
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How to Know Electric Service Voltage at the SEC in Plain Sight
There is one effective way to know the available electric service voltage in a building by merely looking at the overhead electrical wires at the service entry. You will have an idea on the amount of voltage available inside the building by looking at the overhead aluminum SECs and wiring. The subject of visual examination of the aluminum service entry cables and wiring also involves inspecting the electric meters, meter base, electrical service panel, the main switch and other specific aspects of the service entry.
Note that this does not refer to the ground conduit or connection which is typically found in buildings. To conduct your own visual examination and determine the amount of voltage in a service entry, look at the point where the service drop is connected to the service conductors along the entry point.
But this article will focus on determining the volts available at the service entry by plain eyesight. In ordinary terms, the service entry cable is also known as the service conductors. The underground conduit, on the other hand, is called service lateral. With simple visual assessment, you can tell right away that there is an electrical service of 240V because there are three wires attached to the building. Two of these wires have 120 volts each which sums up to the 240V while the third wire is the grounded or electrically charged conductor.
Typically, an aluminum wiring that has 240V includes three connected wires that are attached to the service conductor. These three wires with 240V come from the two wires with 120V or the hot legs and the electrically charged conductor which becomes the third wire.
You will know that a particular service entry has electric service voltage of 120V by mere looking at the wires attached to it. An aluminum wiring that has 120V has only two wires; a 120V power line and a grounded neutral.
The disconnection of aluminum service entry wiring and wiring from the masthead can be perilous. Such blunder usually happens during momentary availing of electricity from the building during building reconstruction or even on new constructions.
There can be 240V supplied to the aluminum wiring with only two wires but they are not commonly used in he US but in some rural buildings in Canada. The 240V is supplied to the building using a lengthy exclusive wire.
The 240V supplied with only two overhead conductors are not made by the utility company’s lines but are usually made in the building. Although such cases are rare in US, such kind of connection is still utilized along the countryside.
Learn how Waldron Electric Heating and Cooling professionals show you what to look for in wirework hazards.
