Electical Contractor

Branch-Circuit, Feeder and Service Calculations, Part LX

| February 2011

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Codes & Standards

When inspiration strikes, I like to select certain sections and articles in the National Electrical Code (NEC) that apply to a particular subject and look at their application. I recently did this with optional standby generators.

| February 2011

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Codes & Standards

The National Electrical Code (NEC) contains nine chapters. The second chapter, Wiring and Protection, is one of four that apply generally to all electrical installations.

All Aboard!

January 2011

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Codes & Standards

Article 310, covering conductors for general wiring, has been totally rewritten for the 2011 National Electrical Code (NEC).

A Law Firm's Concern

Making Neutral Conductors Reach, Tamper-Resistant Receptacles and More

| January 2011

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Codes & Standards

A law firm contacted me about an incident involving safe working clearances in and around electrical equipment.

Charlie Trout

| January 2011

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Codes & Standards

Branch-Circuit, Feeder and Service Calculations, Part LIX

Cables Sharing Runs, Dealing With Inconveniences and More

| January 2011

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Codes & Standards

Every three years, the National Electrical Code (NEC) is revised, but the Code has only been on a three-year cycle since 1975. During the NEC’s 114-year existance, revision cycles have ranged from one year to four years. The first edition of the Code book was published in 1897.

Charlie Trout

| December 2010

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Codes & Standards

If you have a problem related to the National Electrical Code (NEC), are experiencing difficulty understanding a Code requirement, or are wondering why or if such a requirement exists, ask Charlie, and he will let the Code decide. Questions and comments can be sent to codefaqs@earthlink.net.

Branch-Circuit, Feeder and Service Calculations, Part LVIII

| December 2010

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Codes & Standards

This month, Code in Focus covers an optional feeder and service load calculation for two dwelling units that are supplied by a single feeder. There are two methods for calculating services and feeders for one-family dwellings and multifamily dwellings, and either is permissible.

Don't Fence Me In

December 2010

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Codes & Standards

The title of 110.31 in both the 2008 and the 2011 National Electrical Code (NEC) indicates this section deals with enclosures for electrical installations operating at more than 600 volts (V) nominal.

Different Worlds

| December 2010

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Codes & Standards

As a guest speaker at a meeting of electricians, I was asked to address how to determine the number of receptacles required for commercial buildings and if their installation requirements and spacing procedures were regulated in the same manner as for dwelling units.

Implied Responsibility

Mark C. Ode

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Codes & Standards

The 2011 National Electrical Code (NEC) provides a controversial and much-discussed new 110.24 involving field-marking of available fault current on service equipment.

Tray Chic

James W. Stallcup

Sizing Conductors for VFDs, Defining Terms and More

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Codes & Standards

One of my customers is an industrial plant that was informed it needed to upgrade its cable tray systems and bring them up to the minimum codes and standards. They called me with questions pertaining to cable tray installations.

Charlie Trout

Branch-Circuit, Feeder and Service Calculations, Part LVII

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Codes & Standards

Calculating Overcurrent Protection, Transfer Switches and More

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Codes & Standards

Last month’s Code in Focus covered multifamily-dwelling house loads as calculated in accordance with the optional method. This month, the discussion continues with the connected loads for multifamily dwellings as specified in 220.84(C)(4) of the National Electrical Code (NEC).

September 2010

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Codes & Standards

If you have a problem related to the National Electrical Code (NEC), are experiencing difficulty in understanding a Code requirement, or are wondering why or if such a requirement exists, ask Charlie, and he will let the Code decide. Questions can be sent to letthecodedecide@earthlink.net.

Square Peg, Round Hole

Mark C. Ode

| September 2010

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Codes & Standards

Where raceways and cables contain No. 4 AWG or larger conductors and connect to conduit bodies, do these conduit bodies have to meet the same dimension requirements as pull and junction boxes?

How Low Can You Go?