Best practice literature to be covered in our 11 AM session today are listed below.  These codes and standards ensure safety, reliability, and compliance for underground electrical and telecommunications installations:

2028 National Electrical Safety Code

• National Electrical Code (NEC), NFPA 70
  • Relevance: The NEC, published by the National Fire Protection Association, is the primary standard for safe electrical installations in the U.S. Articles 300 (Wiring Methods), 310 (Conductors for General Wiring), and 230 (Services) cover underground wiring, including burial depths, conduit requirements, and direct-burial cables like Type UF and USE-2. For example, NEC 300.5 specifies minimum cover depths (e.g., 24 inches for direct-burial cables, 18 inches for PVC conduit).
  • Key Aspects: Rules for conductor protection, grounding, GFCI requirements, and conduit types (e.g., Schedule 80 PVC). Adopted by most U.S. jurisdictions with local amendments.

ANSI/TIA-568 Series (Commercial Building Telecommunications Cabling Standards)

• Relevance: Governs low-voltage telecommunications cabling, including underground installations. TIA-568.2-D (Balanced Twisted-Pair) and TIA-568.3-D (Optical Fiber) specify performance requirements for cables like Cat6 and fiber optics, including maximum distances (e.g., 100 meters for twisted-pair).
• Key Aspects: Ensures signal integrity, proper separation from high-voltage lines, and compliance for plenum or direct-burial-rated cables. Voluntary unless mandated by local codes.

IEEE 835 (Standard Power Cable Ampacity Tables)

• Relevance: Provides ampacity ratings for underground power cables, critical for sizing conductors to prevent overheating.
• Key Aspects: Includes data for direct-burial and ducted installations, considering soil thermal resistivity and ambient conditions. Often referenced alongside NEC for high-current applications.

UL 83 (Standard for Thermoplastic-Insulated Wires and Cables)

• Relevance: Underwriters Laboratories standard for wires like THWN-2, commonly used in underground conduits. Ensures cables meet safety and performance criteria for wet locations.
• Key Aspects: Specifies insulation durability, temperature ratings, and suitability for direct burial or conduit use. NEC requires UL-listed cables for compliance.

OSHA 1910.305 (Wiring Methods, Components, and Equipment)

• Relevance: U.S. Occupational Safety and Health Administration standard for workplace electrical safety, including underground installations in industrial settings.
• Key Aspects: Specifies approved wiring methods (e.g., armored cable, conduit) and enclosure requirements for underground cable trays or boxes. Focuses on worker safety during installation and maintenance.

CSA C22.1 (Canadian Electrical Code)

• Relevance: Canada’s equivalent to the NEC, governing underground electrical installations. Similar to NEC but tailored to Canadian conditions and regulations.
• Key Aspects: Defines burial depths, conduit types, and grounding requirements. For example, low-voltage cables (<30V) require 6-inch burial depth, like NEC.

Notes:

• Regional Variations: Always consult local building authorities, as codes like the NEC or AS/NZS 3000 may have amendments. For example, some U.S. states reduce burial depths for GFCI-protected circuits (NEC 300.5).
• Low-Voltage vs. High-Voltage: Standards like TIA-568 and ISO/IEC 11801 focus on low-voltage (e.g., <50V) telecommunications, while NEC and IEC 60364 cover both power and telecom.
• Practical Compliance: Before installation, call 811 (U.S.) or equivalent to locate underground utilities, and obtain permits/inspections as required by local codes.
• Critical Examination: While these standards are authoritative, they can lag behind technological advancements (e.g., new cable types like GameChanger exceeding TIA-568 limits). Over-reliance on minimum requirements may limit performance for cutting-edge applications.

Underground Electrotechnology General Conditions and Standard Details

Related:

1793-2012 – IEEE Guide for Planning and Designing Transition Facilities between Overhead and Underground Transmission Lines

The effect of an underground to overhead transition point on the specification of sheath voltage limiters in underground networks

Channel Characteristics Analysis of Medium Voltage Overhead and Mixed Overhead/Underground Cable Power Network

P81/D4, Jan 2025 – IEEE Draft Guide for Measuring Earth Resistivity, Ground Impedance, and Earth Surface Potentials of a Grounding System

Ampere current flows through copper or aluminum conductor due to the movement of free electrons in response to an applied electric field of varying voltages.   Each copper or aluminum contributes one free electron to the electron sea, creating a vast reservoir of mobile charge carriers. When a potential difference (voltage) is applied across the ends of the conductor, an electric field is established within the conductor. This field exerts a force on the free electrons, causing them to move in the direction of the electric field.  The resulting current flow can be transformed into different forms depending on the nature of the device.

Heating: When current flows through a resistor, it encounters resistance, which causes the resistor to heat up. This is the principle behind electric heaters, toasters, and incandescent light bulbs.

Mechanical Work: Current flowing through an electric motor creates a magnetic field, which interacts with the magnetic field of the motor’s permanent magnets or electromagnets. This interaction generates a mechanical force, causing the motor to rotate. Thus, electrical energy is converted into mechanical energy; including sound.

Light: In an incandescent light bulb, a filament heats up ( a quantum phenomena) due to the current passing through it. This is an example of electrical energy being converted into light energy; including the chemical energy through light emitting diodes

Today we dwell on how conductors are specified and installed in building premise wiring systems primarily; with some attention to paths designed to carry current flowing through unwanted paths (ground faults, phase imbalance, etc).   In the time we have we will review the present state of the best practice literature developed by the organizations listed below:

International Electrotechnical Commission

60304 Low voltage installations: Protection against electric shock

Institute of Electrical and Electronic Engineers

National Electrical Safety Code

Insulated Cable Engineers Association

International Association of Electrical Inspectors

National Fire Protection Association

National Electrical Code

Code Making Panel 6

Transcript of CMP-6 Proposals for 2026 NEC

Other organizations such as the National Electrical Manufacturers Association, ASTM International, Underwriter Laboratories, also set product and installation standards.  Data center wiring; fiber-optic and low-voltage control wiring is covered in other colloquia (e.g. Infotech and Security) and coordinated with the IEEE Education & Healthcare Facilities Committee.

Use the login credentials at the upper right of our home page.

Related:

2017 National Electrical Code § 110.5

National Electrical Code: 310.15(B) Temperature Correction Factors

Neher-McGrath Calculation: Cable Calculation ampacity and Thermal Analysis

Voltage Drop Calculation Example

ETAP: Cabling Sizing – Cable Thermal Analysis

System Aspects of Electrical Energy

Impedance Grounding for Electric Grid Surviability

Electric Power Availability: Cold Weather Preparedness

Architecture of power systems: Special cases

Outdoor Deicing & Snow Melting

Campus Outdoor Lighting

High Voltage Electric Service

Campus Bulk Electrical Distribution

Statement from NARUC During its Summer 2018 Committee Meetings

IEEE Education & Healthcare Facilities Committee

Draft Proposals for the 2028 National Electrical Safety Code

Representative State Level Service Quality Standards

MI Power Grid

The National Electrical Safety Code® sets the ground rules and guidelines for practical safeguarding of utility workers and the public.

Submit your changes and review proposals by 15 May 2024: https://t.co/kpf4JyhJSY pic.twitter.com/926L1g8Vxj
— IEEE Standards Association | IEEE SA (@IEEESA) April 21, 2024

Relevant Research

PROCESS, PROCEDURES & SCHEDULE

2025-2026 NESC Revision Schedule

Mike Anthony is ID Number 469 | Proposal period closes 11:59 PM US Pacific Time | May 15

Meeting Notes in red

Loss of electric power and internet service happens more frequently and poses at least an equal — if not greater threat — to public safety.  So why does neither the National Electrical Code or the National Electrical Safety Code integrate reliability into their core requirements?  Reliability requirements appear in a network of related documents, either referenced, or incorporated by reference; sometimes automatically, sometimes not.

NESC Main Committee Membership: Page xii

Apart from the IEEE as the accredited standards developer, there are no “pure non-government user-interests” on this committee; although ANSI’s Essential Requirements for balance of interests provides highly nuanced interpretation.  The Classifications on Page xiii represents due diligence on meeting balance of interest requirements.

In our case, we are one of many large universities that usually own district energy plants that both generate and purchase generate electric power (as sometimes provide var support to utilities when necessary; as during the August 2003 North American outage).  For University of Michigan, for example, has about 20 service points at 4.8 – 120 kV.  Its Central Power Plant is the largest cogeneration plant on the DTE system.

Contents: Page xxviii | PDF Page 29

Absence of internet service is at least as much a hazard, and more frequent, than downed wires.   Is there a standards solution?  Consideration of interoperability of internet service power supported on utility poles  should track in the next revision.

No mention of any reliability related IEEE reliability standards in the present edition.  Why is this?

Section 2: Definitions of Special Terms | PDF Page 46

In the 2023 Handbook, the term “reliability” shows up 34 times.

availability (from Bob Arno’s IEEE 3006-series and IEEE 493 Gold Book revision)

reliability (Bob Arno)

utility (PDF Page 57)

communication | PDF Page 47

list of terms defined in the 2023 National Electrical Code that are new and relevant to this revision: (Article 100 NEC)

Bonding jumper, system and supply

Survivability of communication network signaling

Fiber optic cable mounted on common poles with a medium voltage overhead line standardizing procedure

municipal broadband network, digital subscriber line, surveillance cameras

wireless communication system

010. Purpose | PDF Page 40

Looks like improvement since last edition.  Suggest explicit Informational Note, as in the NEC, using “reliability” and referring to other agencies.  “Abnormal events” could be tighter and refer to other standards for abnormal, steady-state events.   The clarification of purpose is welcomed although a great deal remains uncovered by other best practice literature; though that can be repaired in this edition.

Legacy of shared circuit path standards. Should provisions be made for municipal surveillance, traffic and vehicle control infrastructure.  What would that look like?

011. Scope | Covered PDF Page 40

3. Utility facilities and functions of utilities that either (a) generate energy by conversion from
some other form of energy such as, but not limited to, fossil fuel, chemical, electrochemical,
nuclear, solar, mechanical, wind or hydraulic or communication signals, or accept energy or
communication signals from another entity, or (b) provide that energy or communication
signals through a delivery point to another entity.

5. Utility facilities and functions on the line side of the service point supplied by underground or
overhead conductors maintained and/or installed under exclusive control of utilities located on
public or private property in accordance with legally established easements or rights-of-way,
contracts, other agreements (written or by conditions of service), or as authorized by a
regulating or controlling body.
NOTE: Agreements to locate utility facilities on property may be required where easements are either
(a) not obtainable (such as locating utility facilities on existing rights-of-way of railroads or other entities,
military bases, federal lands, Native American reservations, lands controlled by a port authority, or other
governmental agency), or (b) not necessary (such as locating facilities necessary for requested service to a
site).

012. General Rules | Covered PDF Page 42

For all particulars not specified, but within the scope of these rules, as stated in Rule 011A, design,
construction, operation, and maintenance should be done in accordance with accepted good practice
for the given local conditions known at the time by those responsible for the communication or
supply lines and equipment

General purpose clause could use some work since no definition of “accepted good practice”.  Refer to IEEE bibliography.

Section 2: Definition of special terms | PDF Page 46

Recommendations elsewhere should track here.

 The word “installation” appears 256 times and is generally understood in context by experts.  Suggest borrow from NEC to clarify our concern for including co-linear/communication circuits. 

conduit.  exclusive control, lines, photovoltaic, NEC interactive. qualified

Section 3: Reference

NFPA 70®, National Electrical Code® (NEC®). [Rules 011B4 NOTE, 099C NOTE 1, and 127

IEEE Std 4™-1995, IEEE Standard Techniques for High-Voltage Testing. [Table 410-2 and Table 410-3]
IEEE Std 516™-2009, IEEE Guide for Maintenance Methods on Energized Power-Lines. [Rules 441A4
NOTE 2, 446B1, and 446D3 NOTE, and Table 441-5, Footnote 4]
IEEE Std 1427™-2006, IEEE Guide for Recommended Electrical Clearances and Insulation Levels in
Air-Insulated Electrical Power Substations. [Rule 124A1 NOTE, Table 124-1, 176 NOTE, and 177 NOTE]
IEEE Std 1584™-2002, IEEE Guide for Performing Arc Flash Hazard Calculations. [Table 410-1,
Footnotes 1, 3, 6, and 14]
IEEE Std C62.82.1™-2010, IEEE Standard for Insulation Coordination—Definitions, Principles, and Rules.
[Table 124-1 Footnote 5]

Add references to Gold Book, 1386, etc. IEC since multinationals conform.

Safety Rules for the Installation and Maintenance of Overhead Electric Supply and Communication Line | PDF Page 111

Has anyone confirmed that these tables match NEC Table 495.24 lately?  If it helps: there were no meaningful changes in the 2023 NEC in Article 495, the high voltage article

Section 11. Protective arrangements in electric supply stations | PDF Page 77

A safety sign shall be displayed on or beside the door or gate at each entrance. For fenced or
walled electric supply stations without roofs, a safety sign shall be displayed on each exterior
side of the fenced or wall enclosure. Where the station is entirely enclosed by walls and roof, a
safety sign is required only at ground level entrances. Where entrance is gained through
sequential doors, the safety sign should be located at the inner door position.  (A clarification but no change.  See Standards Michigan 2017 proposals)

Recommend that all oil-filled cans be removed and services upgraded through energy regulations with new kVA ratings

Section 12: Installation and maintenance of equipment

093. Grounding conductor and means of connection

Fences
The grounding conductor for fences required to be effectively grounded by other parts of this
Code shall meet the requirements of Rule 093C5 or shall be steel wire not smaller than Stl WG
No. 5.

D. Guarding and protection | PDF Page 67

124. Guarding live parts| PDF Page 85

Propose roofs required for exterior installations

Part 2. Safety Rules for the Installation and Maintenance of Overhead Electric Supply and Communication Line | Page 72

Section 22. Relations between various classes of lines and equipment | Page 80

222. Joint use of structures | Page 82

Where the practice of joint use is mutually agreed upon by the affected utilities, facilities shall be subject to the appropriate grade of construction specified in Section 24. Joint use of structures should be
considered for circuits along highways, roads, streets, and alleys. The choice between joint use of structures and separate lines shall be determined through cooperative consideration with other joint
users of all the factors involved, including the character of circuits, worker safety, the total number and weight of conductors, tree conditions, number and location of branches and service drops, structure
conflicts, availability of right-of-way, etc.

Reliability considerations for sustaining internet service when power supply is absent. 

Par2 Section 20 Safety Rules for the Installation and Maintenance of Overhead Electric Supply and Communication Line | PDF Page 111

Has anyone confirmed that these tables match NEC Table 495.24 lately?

Part 3. Safety Rules for the Installation and Maintenance of Underground Electric Supply and Communication Lines | Page 220

Renewable energy for internet access

311. Installation and maintenance

A. Persons responsible for underground facilities shall be able to indicate the location of their facilities.
B. Reasonable advance notice should be given to owners or operators of other proximate facilities that
may be adversely affected by new construction or changes in existing facilities.
C. For emergency installations, supply and communication cables may be laid directly on grade if the
cables do not unreasonably obstruct pedestrian or vehicular traffic and either:

1. The cables are covered, enclosed, or otherwise protected, or
2. The locations of the cables are conspicuous.
Supply cables operating above 600 V shall meet either Rule 230C or 350B.
NOTE: See Rules 014B2 and 230A2d.

Part 4. Work Rules for the Operation of Electric Supply and Communications Lines and Equipment | PDF Page 289

When and why was the term “Work” added to the title of this section?   

Core text for the definition of wireless communication system reliability

Appendix E Bibliography| PDF Page 355

Index | PDF Page 398

The word “reliability” appears only three times.  Should it track in the NESC or should it track in individual state requirements.  So neither the NEC nor the NESC couples closely with power and communication reliability; despite the enormity and speed of research.

Public input on the 2029 Revision will be received until April 9th. Over the next weeks and months — typically meeting twice a day every Tuesday — we will pull forward our previous proposals and draft original proposals relevant to the education and healthcare electrotechnical infrastructure of educational settlements.  Link to Proposed Reorganization.

2029 National Electrical Code Panel 1

2029 National Electrical Code Panel 3

Photo at 2723 State Street Office*

Mike was part of the National Electrical Code Quarter Century Club but was at another conference and not able to receive the award at the June conference.  University of Michigan support began in 1993.  IEEE support began in 2014.

*New Office (a short walk across the street) starting October 1: 455 East Eisenhower, Ann Arbor, MI 48108

Current Issues and Recent Research

Today we examine Second Draft transcripts of the Special Equipment Chapter 6 (CMP-12) and product inspection, testing and certification listings that appear Annex A (CMP-1).

Once every eighteen months we spend a week drilling into the National Electrical Code by submitting new proposals or comments on proposed revisions.  Today we review the actions taken by the technical committees on the First Draft.   Responses to committee actions will be received until August 26th.

2026 National Electrical Code Workspace

Premise Wiring

Interconnected Electric Power Production Sources “Microgrids”

National Electrical Definitions

Kitchen Wiring

Solarvoltaic PV Systems

Hospital Plug Load

Data Center Wiring

Electrical Inspector Professional Qualifications

Critical Operations Power Systems

Arenas, Lecture Halls & Theaters

Appliances

Emergency and Standby Power Systems

Luminaires, Lampholders, and Lamps

Electric Vehicle Power Transfer System

Art, Design & Fashion Studios

Wiring for Luminaires in High Ceiling Occupancies