T t H dToronto HydroSt t Li htiStreet Lighting

ExperienceExperience

Presented August 20, 2009ESA Street Light Symposium

Introduction

•Toronto Hydro Corporation is comprised of two main affiliate companies:two main affiliate companies:

Toronto Hydro-Electric System Limited (THESL)(THESL)-Electrical Distribution Toronto Hydro-Electric System Limited serves 687,000 residential and b hbusiness customers across the city.

Toronto Hydro Energy Services Inc. (THESI)y gy ( )-Energy Services Toronto Hydro Energy Services Inc serves large commercial and industrial customers and manages street lighting.manages street lighting.

Introduction

•Today’s presentation:THESL experience with Street Light ContactTHESL experience with Street Light Contact

Voltage

•Today’s presenters and participants:Mary Byrne Manager Standards & Policy PlanningMary Byrne, Manager, Standards & Policy PlanningThor Hjartarson, Manager, System Reliability PlanningBrad McDonald, Manager, Distribution Grid OperationsBrad McDonald, Manager, Distribution Grid OperationsFrancis Szto, Supervisor, Component ReliabilityDaniel Smart, Standards & MaterialsChristopher Kerr, Component Reliability

C V lContact Voltage I id t dIncidents and ResponseResponse

Standard Streetlight

Pole•Concrete or steel

Handhole•Loc. of pole ground (steel poles)•Potential loc. of inline fuse Inline fuse

Handwell•Loc of connection to supply bus

Inline fuse•Can also be in handhole

•Loc. of connection to supply bus

SupplySupply•From cable chamber, tap box, other handwells, etc.

Handwell Standard

Cast Iron Frame

Sidewalk

HDPE Guard

Sonotube Concrete FormedConcrete Formed

Walls

Duct

Demarcation Point in Handwell

•Supply from cable•Supply to individual street Supply from cable

chamber, tap box, other handwells, etc.O d b LDC

light•Owned by streetlighting company Toronto•Owned by LDC,

Toronto Hydro-Electric System Ltd. (THESL)

company, TorontoHydro Energy Services Inc. (THESI)( )

•Conduits and handwell are

d b THESIowned by THESI

Conductors In Handwell

Bare Copper•ground

Black•live

ground

WhiteWhite•neutral

•Blue/Red -live

•Green –ground

Secondary mains

(TW75)

ground (grounded at

cable chamber)

Whit( )

•White -neutral

Contact Voltage Incidents

•Pre 2004 shocks treated as isolated incidentsincidents

Still the case in many situations and jurisdictions

•2004 → Major incident in New York City•30-year-old Jodi Lane fell on a metal30 year old Jodi Lane fell on a metal service box cover in NYC

•Contact voltage was present on the•Contact voltage was present on the structure

•Fatal shock•Fatal shock

Jodie Lane Incident (cont’d)

•Major consequences:Huge increase in scrutiny from public andHuge increase in scrutiny from public and

regulatorCon Ed (LDC for NYC) given 30 days to prove ( ) g y p

law was not broken•Triggered wide scale awareness of contact

lt ivoltage issuesIEEE working group formed (“Working Group

on Voltages at Publicly and Privately Accessibleon Voltages at Publicly and Privately Accessible Locations”)“Jodi Lane Conference” held yearlyy y

Contact Voltage in Toronto

•Two incidents in early 2007Person shocked hen to ching rail on the•Person shocked when touching rail on the Prince Edward viaduct

Conductor in contact with side of handwellConductor in contact with side of handwellAccumulation of salty waterCrews found marrets used by contractors toCrews found marrets used by contractors to

make splices in nearby handwells, HDPE covers were missing-Issues: Construction not to standard, third party access to TH Streetlight handwell

•Dog shocked in Yorkville around the same gtime

Incidents in Toronto (cont’d)

•Toronto Hydro declared Level III Emergency in February 2009 after:Emergency in February 2009 after:

Dog fatally shocked in Nov 2008Dog fatally shocked in Jan 2009og ata y s oc ed Ja 009Reports of children being shocked

•Incidents were unrelated

Overview of Level III Response

•As a result, the decision was made to:Perform a mobile contact voltage scan of thePerform a mobile contact voltage scan of the

entire systemInspect and “make safe” all streetlighting p g g

handwells and handholes•For the duration of the Level III

THESL i d OEB lemergency, THESL received OEB approval to temporarily take ownership of THESI assetsassets

•Purpose was to “make safe”, not necessarily bring up to standardnecessarily bring up to standard

Overview of Level III Response

Identify and di t

1

remediate unsafe areas

+Define defective equipment for

+2

equipment for follow-up work

++Collect condition

data and test

3

new standards

Timeline

•January 30Level III emergency declaredLevel III emergency declared

•January 31 to February 2Began mobilization plans (materialsBegan mobilization plans (materials,

resources, vehicles, media, procedures)Concentrated field work in vicinity of school y

zones•February 3 to February 23

Largest mobilization effort in history of Toronto Hydro (over 1000 people involved)

•February 23•February 23Program completed

What Was Accomplished

Handwells Inspected 11765

Poles Inspected 39821

C ll R i d f P bliCalls Received from Public (re: contact voltage) 268

Individual Pieces ofIndividual Pieces of Material/Equipment

Purchased160000

N b f M U d 1543Number of Maps Used 1543

People Involved 1024

Total Hours Spent 98401

Physical Inspection Findings

140Contact Voltage Distribution

120

80

100

ge

60Vol

tag

20

40

0

Physical Inspection Findings

160

ces

120

ccu

rren

c

80

ltag

e O

c

40

nta

ct V

ol

0

120 50 t 119 11 t 49 1 t 10

Con

120 50 to 119 11 to 49 1 to 10

Voltage Range

Mobile Inspection Findings

•First mobile scan identified 1563 instances of contact voltageof contact voltage

•Second mobile scan identified 177 instances of contact voltageinstances of contact voltage

•Only 15% of locations had voltage in excess of 10 voltsexcess of 10 volts

•More than 60% of contact voltage occurrences were on third party ownedoccurrences were on third party owned and operated assets

Common Sources

•Metallic plates and coversDirect contact with exposed conductor orDirect contact with exposed conductor or

indirectly through another medium (i.e. salt water)

•PolesDirect contact with exposed conductor

•Concrete structures (including sidewalks)Conductive salt water saturates concrete and

a voltage gradient was formed•THESL’s observations are consistent with fi di f th j i di tifindings from other jurisdictions

Communication With ESA

•ESA worked with us to verify repairsAs req’d by O Reg 22/04 THESL provided•As req’d by O.Reg. 22/04, THESL provided ESA with list of locations where contact voltage was foundvoltage was found

•ESA performed follow-up inspections and provided feedback regarding what theyprovided feedback regarding what they found

•THESL is continuing to work with ESA to•THESL is continuing to work with ESA to ensure our infrastructure is safe

Examples of Inspection Findings

120 volts measured

•Split-bolt splice has degraded

Examples of Inspection Findings

Exposed conductor

•PVC tape on split-bolt splice improperly applied

Examples of Inspection Findings

Excavated handwell withhandwell with live conductors

•Handwell with live supply was paved over

Examples of Inspection Findings

Rebar from sidewalk hassidewalk has penetrated the handwell walls

•Damage from civil contractor

Examples of Inspection Findings

Concrete has poured overpoured over into handwell

•Damage from civil contractor

Common Issues

• Aging and degradation of assetsAccelerated by harsh environment includingAccelerated by harsh environment, including water, ice, salt accumulationBrittle and/or cracked cable jackets wereBrittle and/or cracked cable jackets were observed, likely due to repeated hot and cold season cycles

F il dh i• Failure to adhere to construction standards, i.e.

f tt b thi d t t tuse of marretts by third party contractorsfailure to replace guard in handwellsub-standard taped splicessub-standard taped splices

Challenges

• Third party damageEx/ handwells paved over rebar penetratingEx/ handwells paved over, rebar penetrating handwells

• Ownership of assetsOwnership of assetsContact voltage can be detected on third party owned assets, including transit and

ffi l BIA d li h dtraffic poles, BIA owned streetlights and handwells, control cabinets, conduit and other attachmentsWho is responsible?Need a process for communication and

l tiresolution

Challenges cont’d

•Safety by designHow do you ensure the design is as safe as isHow do you ensure the design is as safe as is

reasonably possible?Are you using the correct equipment/materials y g q p /

for the job?-Cables, conductors, connection hardware, civil

t t i it t tistructures, circuit protection•Installation practices

How do you ensure installations are as perHow do you ensure installations are as per standard?How can you minimize the margin for error?y g

Challenges cont’d

•Third party accessNeed to control third party accessNeed to control third party accessPhysical barriers-i e penta-head bolts-i.e. penta-head boltsDesigning infrastructure such that third

parties have no reason to enter your p yinfrastructureEngagement and Communication of proper t d d ti d th i t fstandards, practices and the importance of

public safety

Challenges cont’d

•Data and recordsNo data was available on handwellsNo data was available on handwellsMany non-standard installations due to

amalgamation (i.e. different cables, g ( ,connectors, connection hardware etc.)Locating infrastructure was difficult due to

snow and icesnow and iceData was recorded with PDA’s and/or paper

forms and entered into our GIS systemyAs a result of the inspections, we now have

records for each handwell and streetlight pole

M i F dMoving Forward With O A tWith Our Asset Management PlanManagement Plan

Streetlight Asset Plan

• Level III Emergency Follow Up• Level III Emergency Follow UpImmediate

• Level III Emergency Follow Up• Level III Emergency Follow Up

Near

• Asset Transition• Inspection Methods & Data Collection• Asset Transition• Inspection Methods & Data CollectionNear

Future

H d Miti ti & St d di tiH d Miti ti & St d di ti

Long Term

• Hazard Mitigation & Standardization• Proactive Asset Replacement Strategy• Hazard Mitigation & Standardization• Proactive Asset Replacement Strategy

Level III Emergency Follow Up

•Plans to complete follow up actions from Level III emergency contact voltage inspection are in placeemergency contact voltage inspection are in place

•Where permanent fixes were not possible during the Level III emergency our 2010 EDR filingthe Level III emergency, our 2010 EDR filing proposes to:

Replace hand well lids with non conductive onesGuard handwells from unauthorized accessRepair deteriorated wiring in handwells and on the poleReplace poles that are no longer feasible to repairRevisit “no access” locations to verify there has been no

unauthorized access & contact voltage is not presentunauthorized access & contact voltage is not present

Asset Transition

•Street lighting is not currently part of THESL asset basebase

We are currently pursuing the acquisition of street lighting assets from our affiliate (THESI)

•Once complete, we will incorporate the streetlight assets into our existing asset database

Including asset condition assessments and work done resulting from Level III emergency

Maintenance Program Development

•After incorporation into our asset database, we will verify that the maintenance program forverify that the maintenance program for streetlights:

Provides efficient and adequate inspectionsq pDefines a maintenance cycle, using Reliability Centred

Maintenance methodology, for the inspection of street light assetslight assets

•We must ensure that current asset conditions are taken into accounttaken into account

Older assets are inspected more frequently and more comprehensively

Inspection Methods

•Manual detection and/or measurement using a hand held devicehand held device

Used by most utilities who are required to have a detection/testing program

•Mobile detection from Power Survey Companyy p yUsed on a one-time basis by some utilities, Con Ed on

a regular basis

Manual Detection

•Field worker manually tests structures usingtests structures using either:

Voltage detector to gidentify the presence of contact voltageMulti meter to measureMulti meter to measure

any voltage present with shunt resistorCombination of both

Manual Detection

•Need to be consistent when testing and measuring voltagesmeasuring voltages

Dedicated training required for field personnel to ensure accuracy and consistency of results

•Must use approved equipment and proceduresGround reference for measurements, shunt resistor?

•Some structures will need to be tested at night when they are energized (i.e. streetlight poles)

Manual Detection

•Many utilities specify the HD Electric LV-S-5 handheld voltage detectorg

•5 to 600 VAC

•LED indicates presence•LED indicates presence of voltage

•Cost is ~$700•Cost is ~$700•Similar product available from Extech Fluke Tripletfrom Extech, Fluke, Triplet, Salisbury

•Measure w/ multimeter if voltage present along withMeasure w/ multimeter if voltage present along with shunt resistor

Manual Detection

•AdvantagesEquipment is widely available from multiple vendorsEquipment is widely available from multiple vendors

and relatively inexpensiveThe technology used is mature and equally effective

for both overhead & underground distribution

•DisadvantagesSlow and time consuming processSusceptible to human error

Mobile Detection

Power Survey Company SVD2000

Mobile Detection

•Electric field sensor array attached to a truck which monitors electric field strengthwhich monitors electric field strength

Detects contact voltage as low as 4.5VTruck moves up to 30km/h range of ~9mTruck moves up to 30km/h, range of 9m

•Operator console processes signalsAudible alarm is sounded when voltage detectedAudible alarm is sounded when voltage detectedOperator directed to “hot spots”

•Our 2010 EDR filing proposes a “ContactOur 2010 EDR filing proposes a Contact Voltage Scan” program to provide quarterly scans of the city (630 km2)y ( )

Mobile Detection

•AdvantagesComprehensiveComprehensiveRelatively fast

•DisadvantagesTechnology offered by only one companyTechnology offered by only one companyCan be expensive in comparison to manual detection

Data Collection

Mobile Computing InitiativeP id h dh ld PDA t f i l•Provide handheld PDA to crews performing pole inspectionsEnables real time database pdate of asset•Enables real time database update of asset conditions

•Allows for more robust data collection (ie GPS•Allows for more robust data collection (ie. GPS coordinates, pictures)

•Will help increase response times to high risk•Will help increase response times to high risk issues

Mitigation Strategies

•Prioritization of follow up work based on maintenance inspection data in accordance withmaintenance inspection data, in accordance with our standards

•THESL asset condition tools (Asset ConditionTHESL asset condition tools (Asset Condition Assessment / Health Index Calculator) will help prioritize work from highest potential hazard to lowest. Possible recommendations may include:

Replacement of entire hand well with composite oneUtili i hi h lit l t i l iUtilizing higher quality electrical wireIncreasing electrical insulation of the pole structureInstalling electrical circuit protection and isolationInstalling electrical circuit protection and isolation

THESL Mitigation Strategies

•THESL has included in our 2010 EDR filing:

Replacing 1,000 “high risk” handwells with non-handwells with nonconductive ones

Replacement of 8,000Replacement of 8,000 handwell covers with non-conductive covers

Grounding 2,000 handwellframes where replacement is not possible

Other Mitigation Strategies

•Application of insulating paint to metallic polesNew York Department of Transportation tried thisNew York Department of Transportation tried this

methodUsed “Insul-X” paint rated up to 20VUsed as temporary stop-gap measure

•Some problems were encountered with durability over time

Isolation Transformers

•All grounds are removed on the neutralTransformer electrically isolates SL circuitTransformer electrically isolates SL circuit

•Ground fault can occur without creating a hazardI th i t f il• Increases the margin to failure

•Accepted method already in place by other tilitiutilities

•DisadvantagesNot enough space in current hand wellsRequires more frequent patrolling for detection of

potential ground faultspotential ground faults

In Conclusion

We at Toronto H dro are dedicated to ens ring o r• We at Toronto Hydro are dedicated to ensuring our assets do not pose safety risks to the public

• We are working together with the ESA to mitigate any outstanding issues resulting from the Level III emergencyoutstanding issues resulting from the Level III emergency

W ti l i i t d d d• We are actively improving our own standards and processes to help mitigate sources of contact voltage

THANK YOU !

Questions?Questions?