North San Jose ProjectNorth San Jose Project

North San Jose ProjectNorth San Jose Project Work began on this project in 1999, completed Work began on this project in 1999, completed

in 2001in 2001 The transmission line installed called the The transmission line installed called the

Nortech-Trimble 115 kV line is 4.6 miles long Nortech-Trimble 115 kV line is 4.6 miles long and runs between PG&E’s Trimble Substation and runs between PG&E’s Trimble Substation and a new PG&E Substation called Nortech and a new PG&E Substation called Nortech Substation.Substation.

The conductor is 795 kcmil ACSS/Condor (54/7) The conductor is 795 kcmil ACSS/Condor (54/7) This project added new distribution capacity in This project added new distribution capacity in

the North San Jose area to remedy the area the North San Jose area to remedy the area deficiency caused by increased new constructiondeficiency caused by increased new construction

Why Horizontal Vee Why Horizontal Vee Insulators Were Chosen?Insulators Were Chosen?

Benefits of using a post insulator (no Benefits of using a post insulator (no insulator swing from wind) with longer insulator swing from wind) with longer span lengthsspan lengths

No insulator swing means less right of No insulator swing means less right of way had to be acquired for the way had to be acquired for the transmission linetransmission line

During construction, area land costs were During construction, area land costs were $1Million/acre$1Million/acre

Swivel post insulators used also provide Swivel post insulators used also provide tension relief between uneven spanstension relief between uneven spans

Construction Issues with Construction Issues with Horizontal Vee InsulatorsHorizontal Vee Insulators

Swivel post provided benefits noted Swivel post provided benefits noted previously but created a temporary previously but created a temporary problem for Constructionproblem for Construction

Insulator assemblies provided by Sediver Insulator assemblies provided by Sediver (MacLean Power Systems) had a pin (MacLean Power Systems) had a pin which prevented swinging of the swivel which prevented swinging of the swivel post during installation of stringing post during installation of stringing blocks and during conductor pullingblocks and during conductor pulling

Disadvantage listed by some Disadvantage listed by some manufacturers include concerns over pins manufacturers include concerns over pins not being removed during clipping and not being removed during clipping and prior to the line being placed into serviceprior to the line being placed into service

Other thoughtsOther thoughts

Line crews prefer removable pins on Line crews prefer removable pins on the swivel post type insulatorsthe swivel post type insulators

If pins are not present, crews can If pins are not present, crews can improvise methods to keep the improvise methods to keep the insulator assembly from swinging insulator assembly from swinging during conductor installationduring conductor installation

Pins, if provided, need to be removed Pins, if provided, need to be removed prior to line being placed into prior to line being placed into serviceservice

North San Jose ProjectNorth San Jose Project

Existing conductor Existing conductor transferred to new transferred to new steel poles to be steel poles to be used as a sock lineused as a sock line

Travelers installed Travelers installed in preparation for in preparation for sock line for new sock line for new second circuitsecond circuit

North San Jose ProjectNorth San Jose Project

Top and remove Top and remove wood polewood pole

Note existing dual Note existing dual OPGW fiber optic OPGW fiber optic system will system will remain on wood remain on wood poles to be poles to be transferred after transferred after 115 kV T/Line is 115 kV T/Line is builtbuilt

North San Jose ProjectNorth San Jose Project

Dot com boom Dot com boom occurred during the occurred during the permitting processpermitting process

Horizontal Vee Horizontal Vee insulators reduced insulators reduced the number of the number of structures, while structures, while reducing right of reducing right of way needs for new way needs for new T/LineT/Line

Project had permitting challenges due to its location Project had permitting challenges due to its location in close proximity to high tech building campusesin close proximity to high tech building campuses

Route was selected and permitting process began Route was selected and permitting process began prior to the existence of many of the office buildingsprior to the existence of many of the office buildings

North San Jose ProjectNorth San Jose Project

Steel pole Steel pole prior to prior to installation of installation of insulator insulator assemblyassembly

Close up view of horizontal vee with swivel post Close up view of horizontal vee with swivel post insulatorsinsulators

Sediver assembly used pins to limit insulator Sediver assembly used pins to limit insulator movement during stringingmovement during stringing

Pins were removed after clipping was completedPins were removed after clipping was completed

Line in serviceLine in service Close up view of swivel postsClose up view of swivel posts

North San Jose Project

North San Jose ProjectNorth San Jose Project

Questions/CommentsQuestions/Comments