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2 Surge protective devices (transient voltage surge suppression)

2 Surge protective devices (transient voltage surge suppression)

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APSC FILED Time: 6/10/2015 9:14:01

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IEEE Std

-2011

IEEE Guide for the Protection of Communication Installations from Lightning Effects



equipment it is intended to protect (at least an MCOV rating of 150 V for 120 V service).

Effective response time shall be 5 nanoseconds or less to 8/20 μs waveform.





Suppression shall be line to neutral, line-to-line, line-to-ground, and neutral-to-ground using

discrete components, except delta configurations.



12. Personnel safety considerations

At least the following recommendations should be considered for the safety of personnel:

1.



Personnel should not work on a tower or in the equipment building during an electrical storm.



2.



The use of SPDs with failure indication is recommended and any noted damage to SPD (TVSS)

equipment in the equipment building shall be repaired or replaced immediately prior to any other

work attempted.



3.



Consideration should be given for a minimum of two maintenance personnel working together at

locations prone to lightning strike activity.



13. Equipment building lightning protection system

Consider the following when designing a lightning protection system for the equipment building.

1.



Protect equipment buildings with a traditional lightning protection system using air terminals, etc.,

when they are considered exposed to a direct lightning strike.



2.



Follow NFPA 780 and/or UL 96A [B34] to protect exposed equipment buildings.



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Copyright © 2011 IEEE. All rights reserved.



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IEEE Std

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IEEE Guide for the Protection of Communication Installations from Lightning Effects



Annex A

(informative)

Bibliography

Bibliographical references are resources that provide additional or helpful material but do not need to be

understood or used to implement this guide. Reference to these resources is made for informational use only.

[B1] Anderson, R. B. and Eriksson, A. J., “Lightning Parameters for Engineering Applications,” Electra

No. 69, pp. 65–102, Mar. 1980.

[B2] ATIS 0600321, Electrical Protection for Network-Operator Type Equipment Positions, Aug. 2010. 9

[B3] ATIS 0600334, Electrical Protection of Communications Towers and Associated Structures, Nov. 2008.

[B4] ATIS 0600338,-2004, Electrical Coordination of Primary and Secondary Surge Protection for Use in

Telecommunications Circuits, 2004.

[B5] Block, R. R., The Grounds for Lightning and EMP Protection, 2nd edition. Minden, NV: PolyPhaser

Corp., 1993

[B6] Brashear, K., Lightning and Surge Protection of Modern Electronic Systems, San Antonio, TX: ILD

Technologies, LLC , 2007.

[B7] Cohen, R. L., et al., How to Protect Your House and Its Contents from Lightning. IEEE Guide for

Surge Protection of Equipment Connected to AC Power and Communication Circuits. New York, NY:

IEEE Press, 2005. 10

[B8] DeCarlo, B. A., Rakov, V. A., Jerauld, J. E., Schnetzer, G. H., Schoene, J., Uman, M. A., Rambo, K.

J., Kodali, V., Jordan, D. M., Maxwell, G., Humeniuk, S., and Morgan, M., “Distribution of Currents in the

Lightning Protective System of a Residential Building—Part I: Triggered-Lightning Experiments,” IEEE

Transactions on Power Delivery, vol. 23, no. 4, pp. 2439–2446, Oct. 2008.

[B9] Duckworth, Jr., E. M., “Guide for Protection of Equipment and Personnel from Lightning,” Journal

of Performance of Constructed Facilities, Aug. 2002.

[B10] Duckworth, Jr., E. M. and Duckworth J. S., “GPR-Expert—Ground Potential Rise Protection Using

a High Voltage Interface.” http://gpr-expert.com/. June 15, 1998.

[B11] Frydenlund, M. M., Lightning Protection for People and Property. New York, NY: Van Nostrand

Reinhold, 1993.

[B12] Hart, W. C. and Malone, E. W., Lightning and Lightning Protection. Gainesville, VA: Interference

Control Technologies, Inc., 1988.

[B13] IEC 62305-1-2006, Protection Against Lightning—Part 1: General Principles. 11

[B14] IEC 62305-2-2006, Protection Against Lightning—Part 2: Risk Management.

[B15] IEC 62305-3-2006, Protection Against Lightning—Part 3: Physical Damage to Structures and Life

Hazard.



9

ATIS publications are available from the Alliance for Telecommunications Industry Solutions, 1200 G Street NW, Suite 500,

Washington, DC 20005, USA (http://www.atis.org/).

10

IEEE publications are available from the Institute of Electrical and Electronics Engineers, 445 Hoes Lane, Piscataway, NJ 08855,

USA (http://standards.ieee.org/).

11

IEC publications are available from the Sales Department of the International Electrotechnical Commission, Case Postale 131, 3,

rue de Varembé, CH-1211, Genève 20, Switzerland/Suisse (http://www.iec.ch/). IEC publications are also available in the United

States from the Sales Department, American National Standards Institute, 11 West 42nd Street, 13th Floor, New York, NY 10036,

USA.



21

Copyright © 2011 IEEE. All rights reserved.



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IEEE Guide for the Protection of Communication Installations from Lightning Effects



[B16] IEC 62305-4-2006, Protection Against Lightning—Part 4: Electrical and Electronic Systems Within

Structures.

[B17] IEEE, IEEE Standards Dictionary: Glossary of Terms & Definitions, New York, NY: Institute of

Electrical and Electronics Engineers, 2008. 12

[B18] IEEE Std 80™-2000, IEEE Guide for Safety in AC Substation Grounding.

[B19] IEEE Std 81™-1983, IEEE Guide for Measuring Earth Resistivity, Ground Impedance, and Earth

Surface Potentials of a Ground System.

[B20] IEEE Std 142™-2007, Recommended Practice for Grounding of Industrial and Commercial Power

Systems.

[B21] IEEE Std 1100™-2005, Recommended Practice for Powering and Grounding Electronic Equipment.

[B22] IEEE Std 1428™-2004, IEEE Guide for Installation Methods for Fiber-Optic Cables in Electric

Power Generating Stations and in Industrial Facilities.

[B23] IEEE Std C62.41.1™-2002, Guide on the Surge Environment in Low-Voltage (1000 V and Less)

AC Power Circuits.

[B24] IEEE Std C62.43™-2004, IEEE Guide for the Application of Surge Protectors Used in Low-Voltage

(Equal to or Less Than 1000 V, RMS, or 1200 V, DC) Data, Communications, and Signaling Circuits.

[B25] IEEE Std C62.45™-1992, IEEE Guide on Surge Testing for Equipment Connected to Low-Voltage

AC Power Circuits.

[B26] ITU-T K.11 (01/2009), Principles of Protection Against Overvoltages and Overcurrents. 13

[B27] ITU-T K.36 (05/1996), Selection of Protective Devices.

[B28] Lightning and Insulator Subcommittee of the T&D Committee, “Parameters of Lightning Strokes: A

Review,” IEEE Transactions on Power Delivery, Vol. 20, No. 1, pp. 346–358, Jan. 2005.

[B29] Ma, J. and Dawalabi, F. P., “Modern Computational Methods for the Design and Analysis of Power

System Grounding,” Proceedings of Powercon ’98 International Conference on System Technology, vol. 1,

pp. 122–126, Aug. 1998.

[B30] Motorola14, 15 Communications Enterprise, “The R56 Manual,” Standards and Guidelines for

Communications Sites. Document number 68-81089E50, 2005.

[B31] National Lightning Safety Institute, Lightning Costs and Losses from Attributed Sources.

http://www.lightningsafety.com/nlsi_lls/nlsi_annual_usa_losses.htm, Apr. 2008.

[B32] Rand, K. R., Lightning Protection and Grounding Solutions for Communication Sites. Hayden, ID:

PolyPhaser Corp., 2000.

[B33] Sunde, E. D., Earth Conduction Effects in Transmission Systems. New York, NY: Dover

Publications, Inc., 1968.

[B34] UL 96A, Installation Requirements for Lightning Protection Systems. 16

[B35] UL 1449-2006, Standard for Surge Protective Devices, 3rd edition.

[B36] Uman, M. A. and Rakov, V. A., “A Critical Review of Nonconventional Approaches to Lightning

Protection,” Bulletin of the American Meteorological Society, Vol. 83, pp. 1809–1820, Dec. 2002.

12

IEEE publications are available from the Institute of Electrical and Electronics Engineers, 445 Hoes Lane, Piscataway, NJ 08854,

USA (http://standards.ieee.org/).

13

ITU-T publications are available from the International Telecommunications Union, Place des Nations, CH-1211, Geneva 20,

Switzerland/Suisse (http://www.itu.int/).

14

Motorola is a registered trademark of Motorola Inc.

15

The following information is given for the convenience of users of this standard and does not constitute an endorsement by the IEEE

of these products. Equivalent products may be used if they can be shown to lead to the same results.

16

UL standards are available from Global Engineering Documents, 15 Inverness Way East, Englewood, CO 80112, USA

(http://global.ihs.com/).



22

Copyright © 2011 IEEE. All rights reserved.



TM

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IEEE Std

-2011

IEEE Guide for the Protection of Communication Installations from Lightning Effects



Annex B

(informative)

Lightning protection guide checklist for risk management



B.1 Key considerations for the application of this Guide





Use current division and current blocking to control the dissipation of lightning strike current on

an antenna tower grounding system through multiple paths.







Separate the antenna tower from the equipment building by a minimum of 9 m (30 feet).







Use only a single point grounding system for the equipment building.







Use a bulkhead panel/waveguide hatch for all coaxial cable entry into the equipment building.







Coordinate the location of the (1) bulkhead panel bond, (2) power and telecommunications entry

bond, (3) bond between antenna and equipment building, at the single point ground connection,

and (4) building master ground bar.







Use ac power surge protection at main power entry and critical secondary panels.



B.2 How to use this Guide

Use the NFPA 780 risk assessment guidelines to determine the lightning risk to the structure. Additionally,

in order to determine the potential for equipment damage or destruction and personnel injury or death from

a lightning strike, perform the following risk evaluation. Count the number of items from the list below that

describe conditions at your location:





Lightning damage has occurred here before.







Personnel are located here and use the equipment at this location.







This location is associated with an antenna tower that is within 15 m (50 feet).







This location is in an area of the country that has 30 or more thunderstorm days per year.







This location uses ac power, and does not have surge protected power panels.







This location uses wire-line telecommunication services which have not been isolated using optical

isolation or isolation transformers.







All equipment in this location is not bonded together at one single point on the building grounding

system.







This location has coaxial cables that come directly into the building without going through a

bulkhead panel/waveguide hatch.







The associated antenna tower at this location does not have a grounding system made up of at least

60 m (200 feet) of buried bare ground conducting wire with multiple paths (minimum of 5, each 12

m [40 feet] in length) away from tower base.







This location has coaxial cables that enter at ceiling height (4.5 m to 6 m [15 to 20 feet] above

ground level), and all equipment grounding is done at floor level or below.



23

Copyright © 2011 IEEE. All rights reserved.



TM

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IEEE Std

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IEEE Guide for the Protection of Communication Installations from Lightning Effects



The number of items above that apply indicates your equipment and personnel risk:



Number of Items

2 or fewer

3 to 5

6 to 8

9 or more



Equipment and Personnel Risk

Low

Moderate

Severe

Critical



24

Copyright © 2011 IEEE. All rights reserved.



TM

APSC FILED Time: 6/10/2015 9:14:01

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IEEE Std

-2011

IEEE Guide for the Protection of Communication Installations from Lightning Effects



Annex C

(informative)

Basic concepts for lightning protection of structures

This informative annex presents basic concepts for the electrical protection recommendations associated

with the protection of structures housing communication equipment from the effects of lightning.

Protection of towers are excluded from this annex.

Lightning is a natural phenomenon that causes millions of dollars in damages to communication equipment

each year due to high-voltage surges and transients.

There is no practical effective way to protect structures housing communication equipment from direct

lightning strikes. However these structures may be protected by observing the following items:

1)



Capture the lightning strike.



2)



Conduct current to ground (earth).



3)



Dissipate current into ground.



4)



Bond all grounding conductors.



5)



Protect from surges on incoming ac power line and on telecommunications (data/signal line).



A systematic approach includes grounding and bonding, lightning and surge protection to safeguard and

protect the structures and the equipment inside them.

The first item involves capturing the lightning strike at the strike point. In order to accomplish this capture,

the structure must have a dedicated lightning protection system that includes air terminals at key locations.

The second item involves directing the lightning current to ground (earth) via the down conductors. The

down conductors are cables designed to conduct safely the lightning current to earth.

The third item deals with dissipating the lightning current into the structure’s low impedance grounding

system. A low resistance grounding system is not sufficient since the lightning surges are impulses of very

short time duration.

The fourth item deals with the electrical bonding of all the separate equipment grounding points

(telecommunications, electrical, and metal objects) to create one equipotential ground plane. During a

lightning strike the equipotential ground plane will ensure that all the equipment will rise to the same

potential, as the ground potential goes up, thus minimizing equipment damages.

The fifth item involves the electrical protection of all the entry points (ac power line and

telecommunications) to the facility. This involves placing SPD on all outside lines that come into the

structure. These lines, whether aerial (overhead) or underground, can bring the lightning surges into the

structure unless properly protected.



25

Copyright © 2011 IEEE. All rights reserved.



TM

APSC FILED Time: 6/10/2015 9:14:01

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IEEE Std

-2011

IEEE Guide for the Protection of Communication Installations from Lightning Effects



Annex D

(informative)

Power-line isolation: theory and application



D.1 LGPR and equipotential planes

The ideal prevention of LGPR is provided by an equipotential plane. This ideal can be approximated within

shelters and cabinets that are configured with a single point ground.

However, the ac power line provides a reference to lower potential ground during a LGPR event.

The safety ground between the shelter or cabinet and the power neutral ground presents a high inductance

relative to the rise time of the LGPR wave form. Vertical grounds characteristic of most shelters and all

cabinets also react inductively to the mid-range frequencies of lightning. (See DeCarlo et al. [B8] for

additional information.)

Consequently, the bi-directional conductivity of grounding and the signal cable or antenna SPDs create a

secondary fault path on the power circuits between the shelter or cabinet and the power neutral ground.

Refer to 5.2.2 and Figure 5.

Enhanced radial grounding at a tower site will mitigate the LGPR severity, but creating an equipotential

plane between the shelter and power-neutral grounds is not feasible. Blocking the fault current through the

ac service by preemptive disconnection of the ac power is the only certain protection for this fault path.



D.2 LGPR detection and isolation activation

The ground strike discharge radiates high voltage through the earth’s surface, referred to as lightning

ground potential rise (LGPR). The severity and range of earth-bound LGPR is determined by the lightning

current characteristics and soil resistivity.

The LGPR radiated by approaching lightning storms is detectable several miles distant by a grounded

dipole or flat-plate detector. The detection sensitivity is adjustable to limit the detection range to

threatening conditions.

The detector controls a contactor in series with the ac service. The response time of the contactor activation

must be less than 20 ms to preempt threats posed by near-proximity strikes.



D.3 Back-up power and rectifier implications

Continuous operation is maintained by standby power systems (battery plant and generator if present) until

ac power is automatically restored after the threat has passed.

The disconnection period is selectable. Subsequent lightning threats during the disconnection period refresh

the count-down timer.

To minimize generator cycling, the disconnection period may be extended, the isolation timing can be

coordinated with the automatic transfer switch (ATS), and generator timers and the contactor may be

installed on the load side of the generator.

26

Copyright © 2011 IEEE. All rights reserved.



TM

APSC FILED Time: 6/10/2015 9:14:01

AM:1692

Recvd

6/10/2015 9:10:59 AM: Docket 14-069-C-Doc. 109

IEEE Std

-2011

IEEE Guide for the Protection of Communication Installations from Lightning Effects



Re-connection of the ac service should be timed at the 0 voltage cross-over to mitigate power recovery

transients and in-rush current.



D.4 Power line transient protection

Direct or near-proximity strikes to power lines induce severe transients that may overwhelm protective

systems. Detection of LGPR radiated by approaching lightning storms allows preemptive disconnection of

the ac service, effectively isolating the site equipment from lightning induced power-line transients.

AC power is automatically re-connected after the power stabilizes within selective power quality

thresholds.



27

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