Our Blog

Our Blog

Welcome to Our Blog

Here you will find articles and information about Bobo Technologies, the NEC and the Electrical Industry in general.  including updates on code changes and …

Use of Tightening Torque Tools where instructions are Provided by Manufacturer

110.14(D) Installation.  Where a tightening torque is indicated as a numeric value on equipment or in installation instructions provided by the manufacturer, a calibrated torque tool shall be used to achieve the indicated torque value, unless the equipment manufacturer has provided installation instructions for an alternative method of achieving the required torque.

Comment:  Most electricians are familiar with the old adage “hand tight plus a quarter turn”, but studies have shown that approximately 75% of terminations are not within +/- 20% of the manufacturer’s recommended torque value where a calibrated torque tool has not been used.  It is common practice to use a torque tool on larger switchgear, however the 2017 NEC now makes it clear that a torque tool must be used whenever a manufacturer provides torque values for the terminations on their equipment, so that the most reliable, low-resistance connection is made.

Limited Access to Working Space About Electrical Equipment

110.26(A)(4) Limited Access.  Where equipment operating at 1000 volts, nominal, or less to ground and likely to require examination, adjustment, servicing, or maintenance while energized is required by installation instructions or function to be located in a space with limited access, all of the following shall apply:

(a) Where equipment is installed above a lay-in ceiling, there shall be an opening not smaller than 559 mm x 559 mm (22 in. x 22 in.), or in a crawl space, there shall be an accessible opening not smaller than 559 mm x 762 mm (22 in. x 30 in.).

(b) The width of the working space shall be the width of the equipment enclosure or a minimum of 762 mm (30 in.), whichever is greater.

(c) All enclosure doors or hinged panels shall be capable of opening a minimum of 90 degrees.

(d) The space in front of the enclosure shall comply with the depth requirements of Table 110.26(A)(1).  The maximum height of the working space shall be the height necessary to install the equipment in the limited space.  A horizontal ceiling structure member or access panel shall be permitted in this space.

Comment:  The requirements for limited access working space for duct heaters contained in 424.66(B) of the 2014 NEC have been relocated to 110.26(A)(4) and expanded to include all equipment operating at 1000 volts, nominal, or less to ground that are likely to require examination, adjustment, servicing, or maintenance while energized.  This could include equipment such as motors, air-handling equipment, or transformers.  The access opening in a grid ceiling is based on a standard 2 ft. x 2 ft. lay-in ceiling grid opening.  The dimensions for a crawl space opening is based on similar requirements for signs at 600.21(E) with a minimum width of 30 in. or the width of the enclosure, whichever is greater.  Enclosure doors or hinged panels must be capable of opening a minimum of 90 degrees.  The height requirement is based on the minimum height required to install the equipment in the limited space, instead of the 6 ½ ft. or height of the equipment required by 110.26(A)(3).

Individual 120-Volt – 20-Ampere Branch Circuit for Dwelling Unit Garage Receptacles

210.11(C)(4) Garage Branch Circuits.  In addition to the number of branch circuits required by other parts of this section, at least one 120-volt, 20-ampere branch circuit shall be installed to supply receptacle outlets in attached garages and in detached garages with electric power.  This circuit shall have no other outlets.

Exception:  This circuit shall be permitted to supply readily accessible outdoor receptacle outlets.

read more…

GFCI Protection for Personnel for Lighting Outlets in Crawl Spaces

210.8(E) Crawl Space Lighting Outlets.  GFCI protection shall be provided for lighting outlets not exceeding 120 volts installed in crawl spaces.

Comment:  GFCI protection for lighting outlets not exceeding 120 volts is now required where lighting outlets are located in crawl spaces, at or below grade level, of dwelling units or non-dwelling units.  At least one lighting outlet containing a switch or controlled by a wall switch shall be installed where a crawl space is used for storage or it contains equipment requiring servicing. (210.70(C))

GFCI Protection for Personnel in Non-Dwelling Unit Unfinished Basements

210.8(B) Other Than Dwelling Units.  All single-phase receptacles rated 150 volts to ground or less, 50 amperes or less and three-phase receptacles rated 150 volts to ground or less, 100 amperes or less installed in the following locations shall have ground-fault circuit-interrupter protection for personnel.

(10) Unfinished portions or areas of the basement not intended as habitable rooms

read more…

Expansion of GFCI Protection for Personnel in Other Than Dwelling Units

210.8(B) Other Than Dwelling Units.  All single-phase receptacles rated 150 volts to ground or less, 50 amperes or less and three-phase receptacles rated 150 volts to ground or less, 100 amperes or less installed in the following locations shall have ground-fault circuit-interrupter protection for personnel.

Comment:  The 2014 NEC only required GFCI protection for personnel for 125-volt, single-phase, 15- and 20-ampere receptacles located in areas where GFCI protection was required.

read more…

Shortest Path Method of Measurement for GFCI Protection at Sinks

210.8 Informational Note No. 2.  For the purposes of this section, when determining distance from receptacles the distance shall be measured as the shortest path the cord of an appliance connected to the receptacle would follow without piercing a floor, wall, ceiling, or fixed barrier, or passing through a door, doorway, or window.

210.8(A)(7).  Sinks – where receptacles are installed within 1.8 m (6 ft.) from the top inside edge of the bowl.

read more…

Shortest Path Method of Measurement for GFCI Protection of Receptacles

210.8 Informational Note No. 2.  For the purposes of this section, when determining distance from receptacles the distance shall be measured as the shortest path the cord of an appliance connected to the receptacle would follow without piercing a floor, wall, ceiling, or fixed barrier, or passing through a door, doorway, or window.

Comment:  A new Informational Note No. 2 now provides clarification on the measurement technique to be utilized when measuring receptacles requiring GFCI protection.

read more…

Identification of Ungrounded Conductors for Existing Installations where a Different Voltage System is Added

210.5(C)(1), Exception.  In existing installations where a voltage system(s) already exists and a different voltage system is being added, it shall be permissible to mark only the new system voltage.  Existing unidentified systems shall not be required to be identified at each termination, connection, and splice point in compliance with 210.5(C)(1)(a) and (b).  Labeling shall be required at each voltage system distribution equipment to identify that only one voltage system has been marked for a new system(s).  The new system label(s) shall include the words “other unidentified systems exist on the premises.”

read more…