LECO Exp

PSS

LECO

TfDDLO

SA

LBC

LBC

LBS

11 kV33 kV

CEB

Service line

T-OffABCFDS

Consumer

MCB

Meter

Chapter 2 LECO Industrial Training Report

2.9 Engineering Division

2.9.1 Introduction

LECO Engineering Division is responsible for planning, designing of distribution system,

carrying out special projects, procurement of goods and training of LECO staff. This division is

supervised by the Head of the Engineering Division Dr.Narendra De Silva. I gained a good

training at this division within one week and I was trained under the Chief System Development

Engineer Mr.C.S.Unagolla.

2.9.2 LECO Network

Since it was the first week of my training in LECO I obtained a basic knowledge about the

LECO Company and its network. The electricity transfer voltage from CEB to LECO network is

11kV. Twenty Nine 33/11kV primary substations supply power to the LECO owned network

comprising of 1017km of 11kV network, 3065 km of 400V network and 6184 distribution

substations s. Schematic of the LECO system is given below.

Department of Electrical Engineering 8University of Moratuwa

PSS – Primary Substation LBS – Load Break Switch LBC – Load Break Cutout DDLO – Drop Down Left Over FDS – Fuse Disconnector Switch ABC – Arial Bundle Conductor MCB – Miniature Circuit Breaker SA – Surge Arrester

Figure 2.2 SCHEMATIC OF LECO SYSTEM


2.9.3 Arial Bundle Conductors (ABC)

LECO uses ABC conductors in their distribution overhead power lines which has 5 insulated

conductors bundled tightly together. In the bundle 3 conductors stand for the three phases, one

for the neutral conductor and the other cable stands for supplying power to street lights. The

main purpose of using these bundle conductors is safety of the public and workers. When the

bundle is connected to the poles the neutral cable is used to hold the whole bundle’s weight.

2.9.4 Geographical Information System ( GIS )

Today LECO is proud of having comprehensively updated GIS mapping system of half meter

accuracy for entire governed area to keep track of the available assets of the company. GPS data

is collected in the field using the GPS antenna and stored with coordinates using a data logger.

Then the collected data will be transferred to a software called “Pathfinder” and subjected to

differential correction and the map will be imported to AUTOCAD Maps. Then the particular

map is linked with the GIS map to update the existing map. This map drawn by the branches is

sent to the head office. Then the final map is prepared at the head office. I was also able to study

the way of preparing some maps at the head office. Section of a GPS / GIS map is provided in

the Annex A11,2,9,4.

2.9.5 Other Training Experiences

When I was there I was able to study the 4 volumes of the Company’s Construction Manuals

which contain concepts and design criteria, general arrangements drawings, equipment selection

charts and equipment drawings. These construction manuals provide a detailed reference to

maintain a standard of constructions. As well as I learned the local and foreign procurement

procedures of the company. When the cost of goods to be bought exceeds Rs 10 million tenders

are been called otherwise quotations are been called. This process also differs according to the

type of the supplier as foreign or local.

In addition to that I learned the procedure of preparing a Load Forecast Report and I studied the

Load Forecast (2010 – 2015) report published by System Development Branch.

Department of Electrical Engineering Page 19University of Moratuwa


2.10 Kalutara Branch Office

2.10.1 Introduction

LECO has been divided to 7 branches according the regions to maintain its operations. A branch

is headed by a Branch Manager is assisted the Branch Engineer, Branch Accountant and

Administrative Officer. Branch Engineer is responsible for the network operations and customer

services while the Branch Construction and Planning engineer is responsible for the asset

management function. The Branch Accountant is responsible for the financial accounting and

the Branch Administration Officer is handling the administration of the branch. I got the chance

to train for one week under the Branch Manager at the Kalutara Branch.

2.10.2 Customer Billing and Revenue Collection

When I was there I learned about the tariff categories of the company, customer billing process

and revenue collection procedures. LECO distributes electricity to nearly 460,000 customer

based on six major tariff categories. The highest energy consumption of the network is also the

Domestic customers which amount to 44% of our total energy sales. Customers’ average

consumption under six tariff categories in year 2008 is given below.

Customer Category Average Consumption (kWh)

Percentage from the total

Domestic 469326 43.97%

Religious 7067 0.6%

General Purpose 278035 26.05%

Industrial 242824 22.75%

Hotels 42420 3.97%

Street Lighting 25595 2.3%

Issuing bills is done by the revenue officers for every 30 days period by visiting the consumers.

If there is any mistake with the revenue officers’ bill calculations it can be detected by the LECO

Billing System and correction will be done by the next month’s bill.


Table 2.3 LECO CUSTOMERS’ AVERAGE CONSUMPTION IN YEAR 2008


To collect the bill payments Private Bill Payment Collection agents were introduced in addition

to the Banks at the early stages. Other than that now various modes of payment facilities such as

internet payment, credit card payments, and automatic bill payment schemes are available to

customers and also system is updated online.

2.10.3 Non Payment Disconnection

If an issued bill is not settled within 14 days a notice of disconnection is sent through the next

month’s bill to the customers. A model of Notice of Disconnection is provided in the Annex

A12,2,10,3. If the customer further fails to settle the payments within 10 days the disconnection

operation is taken into action and 2% of the bill value also will be added to the bill. After settle

all the arrears payments and disconnection processing fees the customer will be able to get the

connection again.

2.10.4 New Connection and Meter Testing

New connection can be obtained from LECO as a permanent supply, temporary supply or

temporary permanent supply by submitting an application to a Customer Service Centre or

Branch along with all the required proof documents. Then after the inspection and Estimation

approval the connection is provided.

Normally Meter Testing duties are done in a case of complains regarding a meter. The customer

should fill a request form and the payments the testing duty is taken into action. When testing a

meter another parallel meter is fixed in the requested place and check whether there is any

difference between two meter readings. If the error is greater than 2.5 % meter is replaced as

well as the request fee is also refunded.


In addition to the above mentioned experiences I was able to obtain a fair knowledge about the

route survey procedure, estimation preparing procedure and job costing procedure which are

carried out when designing a new line. And also I learned how to do construction work and pole

erection when implementing a new line. As well as I obtained a fair knowledge about the duty

which is done by the Administration Division of the Branch.



2.11 System Operation Division

2.11.1 Introduction

The operations division is mainly responsible for carrying out day to day distribution system

operations such as controlling, upgrading and consumer relations in its network. I was appointed

to this division for one week and I trained under the Control Engineer of the Distribution Control

Centre.

2.11.2 Distribution Control Centre ( DCC )

Distribution Control Centre plays an important role to maintain continuous and reliable power

supply by constantly monitoring and controlling the performance of the entire distribution

system. The operational staff involves operation throughout the 24 hours of the day and there is a

mimic board which contains the LECO HV lines’ switch diagram to identify the current situation

easily. Power supply interruption scheduling is another major task carried out by the DCC. Other

than interruption scheduling other functions of the DCC can be listed as follows.

Alternate supply arrangements for customers during supply outage.

Procurement of new equipment to the LECO distribution system.

Monitoring and analysis of the power failures and provide instructions to the field staff to

restore power supply without delay.

Preparation of daily and monthly Outage Reports which contain details of planned

interruptions and power failures based on branches.

Preparation of monthly Consumer Service Calls Reports by obtaining the daily reports of

the consumers’ complaints received to CSC s, Branches and DCC.

A copy of a daily outage report received to the DCC is provided in the Annex A13,2,11,2.

Electricity Supply Outage Report contains some important indices which can be contributed to

maintain the stability of the system and decide the precautions. These indices are calculated

based on the collected details of the planned interruptions and power failures. Details and the

formulas of those indices are provided in the Annex A14,2,11,2.

When I was at the DCC I was able to study and obtain a fair knowledge about the above

mentioned duties.



2.11.3 Interruption Scheduling

Power supply interruptions for routine maintenance work or construction are made by the

Customer Service Superintends through a Request Form which contains all the details such as

feeder name, section, related primary substation, purpose and time regarding the interruption

required. After receiving the Interruption request the Control Engineer and the Senior Controller

analyze the availability and take the final decision as well as fix a date for the particular

interruption. Then the Company informs the ordinary customers about the planned power

interruptions through media and the Bulk Supply customers individually. After that, instructions

are provided through a switching instruction form with a diagram of isolation to the field staff for

switching operations. Then the work permit is issued for the field staff after isolation of high

voltage lines and related terminal equipment, and also reversal of the operation is done after

completion of work and the work permit is cancelled. When the switch operation is done

operator should communicate with DCC.

2.11.4 Meter Test Lab

During that week I was able to visit the meter test lab of LECO situated in Ekala. The major

functions of that lab are bulk and retail meter testing, meter repairing and commissioning. At

there I was able to observe how to repair the meters which had been sent to the lab due to their

malfunction. Almost all the defected meters of LECO are sent to this place to repair. After

undergoing repair at the test lab the meters are being tested for accuracy. Newly manufactured

meters are also commissioned in the test lab to check their accuracy. Test lab consists of a test

bench which can be used to test 10 meters at the same time.


When I was there I experienced how to test

and commission the repaired and new

meters before using in the field.

Figure 2.3 METER TEST BENCH


2.12 Kalutara Customer Service Center

2.12.1 Introduction

Each branch area of LECO has been further divided into three or four Customer Service Centers

(CSC) with an approximately 20,000 customers for each center. Each customer service center is

equipped with 24 hour maintenance team with the set of equipment such as fleet of vehicles,

hydraulic platform trucks, digger cranes and other associated heavy duty equipment which has

facilities to attend any breakdown call within 20 to 30 minutes of time. The customer service

centers are located in such a manner that the breakdown maintenance teams can attend any fault

within 30 minutes. This entire breakdown maintenance operation is centrally monitored through

the Company’s control centre through a LECO owned radio communication network. Apart from

those, planned construction work, new connections, disconnections, reconnections, service line

estimations, pole shifting, service line shifting and meter shifting are also carried out by CSCs. In

addition to that supervision of the revenue officers, who issue the bills, is also done by the CSCs.

According to my schedule I was appointed to Kalutara Customer Service Center of LECO for

one week training. At there I was trained under the Customer Service Superintend of the CSC

Mr.Senaratne. When I was there I was able to involve breakdown repairs and maintenance work

and I obtained many experiences.

2.12.2 Replacing a pole

During that week I got the chance to involve a duty of replacing a pole which has been damaged

due to fall of a tree on the line.


I went there with the maintenance

gang. I could see that the pole had been

cracked from its ground level. First of

all the wire bundle was detached from

the pole. Then the cracked pole was

removed using the crane. After that the

new pole was planted.

Figure 2.4 REMOVING THE DAMAGED POLE


2.12.3 Shifting a meter and a service line


After planting the new pole I was able to

observe the way of attaching the wire bundle to

the pole using clamps. The bundle was

connected to the pole using the neutral wire.

Next day I went with the technicians to do a duty

of customer requested meter shifting. Shifting the

service wire also included to this duty. At there I

was able to observe and study the way of

connecting the load wire and the service wire to

the meter.

When shifting the service wire we could identify

that the length of the service wire is not adequate

to shift to the place where the meter was shifted.

Therefore service wire was extended by

applying a joint. The 2 wires of the service

line were extended by connecting

additional wires. Two LV line connectors

were used to apply the joint and the

connection was tightened using a

Climping tool.

Figure 2.5 ATTACHING THE BUNDLE TO THE POLE

Figure 2.6 SHIFTING A METER

Figure 2.7 APPLYING A JOINT USING CLIMPING TOOL


2.12.4 Repairing a broken service line

2.12.5 Breakdown Registry

CSC maintains a registry to record the customer complains. Each of such complain is recorded

with the details such as time of receiving the complain, mode of receiving the complain, type of

the fault, name and address of the complainer, repairing completing time and etc. The records of

this registry are sent to the DCC monthly.


Apart from the above mentioned experiences I was able to involve another service wire shifting

duty. The wire was shifted to another pole since the line was crossed over another land.


When I was there I got the chance to go with

the breakdown to repair a broken service line.

But the service wire was connected by applying

a temporary joint since the service wire is very

old and had been recommended to replace.

When applying this temporary joint only the

phase wire joint was insulated.

In addition to that I went with the technicians to give

a new domestic connection. And I observed the

procedure of installing the meter box and the meter.

As well as I observed the way of connecting the

service wire to the existing bundle conductor using

T-Off connectors.

Figure 2.8 TEMPORARY JOINT

Figure 2.9 T-OFF CONNECTOR

LECO Exp

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