third party antenna mounting on lattice steel and monopole...

SEPTEMBER 4 - 6, 2019

Third Party Antenna Mounting on Lattice Steel and Monopole Towers

Sergio Arambula – Southern California EdisonJeffery Collins, P.E. – Southern California Edison


AgendaIntroductionAntenna TechnologySCE Assets and InfrastructureAntenna Project OverviewStructural AnalysisSite ConstructionIndustry Practices ConclusionQuestions


Antenna Technology Created in 1997 Wireless Carriers

T-Mobile (MetroPCS/Cingular) AT&T Verizon Clearwire Sprint (Nextel)

Macro Site Equipment Antennas Radios (RRUs) Surge Protectors Diplexers/Combiners

1997

2019


Antenna Technology 850 total macro sites 1997-2010

60 macro sites per year 2013-Present

170 macro sites per year 90% MODS, 10% new builds

2018 280 total macro sites 400 macro sites for 2019

Future Forecast Growth and expansion New Technologies, New

Communities


Southern California Edison’s Assets

SCE services the following: 15 million people 5,000 large businesses 280,000 small businesses 180 incorporated cities 15 counties 50,000 square miles

SCE Assets: 12,600 miles of transmission lines

91,300 miles of distribution lines

20,000 bulk power structures


Antenna Project Overview

Edison Carrier Solutions (ECS) Site Walks Scheduled Zoning Drawings Published and Presented Responsible Engineer Analyzes Rejection, Approval, or Approval with MOD Steel Order Ends Project Life Cycle


Structural Analysis – Manuals/Software

ASCE MOP 74 – Guidelines for Electrical Transmission Line Structural Loading – latest version

General Order 95 – Overhead Electrical Line Construction – latest version

ANSI/TIA-222 – Structural Standard for Antenna Supporting Structures and Antennas – latest version

SCE Wind Maps – SCE created wind loading zones

Power Line Systems software: PLS-CADD, PLS-Tower, and PLS-Pole –latest release


Structural Analysis: PLS-CADD LiDar data for all major bulk 220kV and 500kV T/L In-situ Loads Used LiDar data vs. PLS-CADD Lite vs. Google Earth Data


Structural Analysis: PLS-CADD

Weather Condition Wire Temp (°F)

Wind Prss./Vel. (psf)/(MPH)

Radial Ice (in.)

Ice Den. (lbs./ft3)

Wire Wind Ht. Adjust Model

Wire Gust Response Factor

GO-95 Light 25 8.0/55.9017 0 0 None None

GO- 95 Heavy 0 6.0/48.4258 0.5 57 None None

NESC Extreme Wind (CA)* 60 18.496/85 0 0 NESC 2012 NESC 2012

ASCE-74 Extreme Wind* 45 18.496/85 0 0 ASCE 74-2009 ASCE 74-2009

Insulator Swing** 25 8.0/55.9017 0 0 None None

*: Or, SCE line specific criteria based on meteorological study.**: Weather case for insulator swing check (compare swing before (creep) and after (initial).

Weather Criteria


Structural Analysis: PLS-CADD

Weather Condition Over Load Factors

Tower Wind Area Factor

Structure Wind Model

GO-95 Light 1.5 1.5 Wind on FaceGO- 95 Heavy 1.5 1.5 Wind on FaceNESC Extreme Wind (CA)*

1.0 1.0 NESC 2012

ASCE-74 Extreme Wind* 1.0*** 1.0 ASCE 74-2009FGO-95 Grade A Crossing**

1.0 1.5 Wind on Face

Lattice Tower Loading Criteria

*: Or, SCE line specific criteria based on meteorological study.**: For crossing of limited access highways, exclude this criteria for tower not originallydesigned for GO 95 crossing. Use 1/3 total conductor phases broken.***: Towers less than 25 years services use OLF = 1.25


Structural Analysis: TIA-222 Calculations


Structural Analysis: PLS-Tower

Advance Tower Analysis and Design System (ATADS) previously used

Most common towers used on SCE’s bulk power system are designed using PLS-Tower

Responsible engineer checks model for modifications, adds clip angles


Structural Analysis: A-Frame/Monopoles

Antennas mounted on both monopoles and A-Frames are not welded to the structure itself but are chained by mounting kits provided and specially designed by our vendors.


Site Construction

One to Three Weeks to Complete for MODsUp to 5 Months to Construct New Sites 4 to 6 Weeks to Receive Steel Material Certified Electrical Workers Install Reinforcements Field Crews Install Cell Sites Final Project Approval Granted By RF Engineers Final Site Approval Granted by City Engineers


A B C D

E F G H


Industry Practices SCE mounts directly onto towers Antenna installations are always below

energized conductors SCE standards requires a certified

electrical worker if mounts are near or above the conductors

SCE requires workers to work from safe distances based on voltage levels

Installations are done from cranes Some utilities will mount antennas above

the conductors with the use of a steel mast

Outages must be taken for the installation to occur

Lineman and certified workers will climb the tower itself and hoist equipment

Some utilities have eliminated installation of antennas on higher voltages


Conclusion

Antenna Technology SCE Infrastructure Antenna Project Process Structural Analysis Site Construction Industry Practices


Questions?


Thank you !

Sergio Arambula – Southern California EdisonJeffery Collins, P.E. – Southern California Edison

third party antenna mounting on lattice steel and monopole...

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