(14/6/2010-25/06/2010)

This unit is related with planning unit.Contruction unit will construct what already planned by planning unit.The flowchart of that process are given below

(1/6/2010-11/6/2010) Planning

For all distribution capital projects financed via CAPEX, working paper has to be prepared and approved before implementation :

a)capital work authorizationform(CWA/BKKM)

b)Minor cost cost sheet(Mwcs/lkkk)

-for project cost les than RM 50 000

-does not involved MV network expansion/ change

-normally associated with service extension

A complete BKKM comprises of

a) Standard schedule of TNB

b) detail project description

c) location plan and As-fitted site plan

d) system schematic diagram complete with new proposalfor all MV expansion

e) Approved copy of MV technical proposal

f) Copy of supply application letter and initial load data submitted by consultant

g) copy of endorsed connection charge calculation letter

(18/5/2010-25/5/2010) Meter

At the commercial affair, it responsible to the costumer account where all of the information of the billing accounts were organized and updated here. Also cut off electricity for non pay user were also done here, where team will respond to unpaid bill even though warning notice had been delivered. In the service and meter section the responsibility were installing new meter or upgrade the system. The job scope was to estimate, making cost sheet, services and install meter.

The metering section is responsible for the installation and replacing of meters, which gauge the electricity use by either the Ordinary Power Consumer (OPC) or the Large Power Consumer (LPC)

(6/5/2010-17/5/2010) services

Services are lines that tap off from mains (overhead or 5 foot way) to feed one consumer or group of consumer. A 5 foot way main is a cables or PVC cables which run along the eaves or wall of terrace houses or 5 foot way of shop houses. 7.5 meter poles are used, however if clearance are insufficient 9 meter poles may be used if there is insufficient ground clearance at the services cross the road and when the length of services exceed the maximum permissible length of the conductor used. In situation such as road crossing and telephone line crossing, where clearance cannot be obtained by using standard height poles, an extended pole support mat be used. Services are connected to 5 foot way mains using junction boxes. Junction boxes can be used up to a maximum size of 19/1.53. Connection of services to consumer meter board, the phase conductor is terminated at cut outs and neutral is terminated at neutral link. There are two sizes of cut outs 60 amp (for conductor sizes 7/2.14 mm) and 100 amp (for conductor sizes 19/1.53 mm and 19/2.14 mm)

Material used for the service installation
1. Dead end clamp
2. ‘J-Hook’
3. Bolt and nut
4. ‘Pendakap D’
5. Insulated piercing connector ( IPC )
6. Wonpiece insulator
7. Suspension clamp
8. Chasing
9. Neutral link
10. 30A and 60A cut out fuse for single-phase and three-phase
11. Material and equipment that related with service installation.

(27/4/2010-5/5/2010) SAVR -(Low Voltage Overhead System )

The SAVR are responsible to fix the end connections from the TNB Distribution supply cables to the consumer’s meter. This section basically receives the electrical fixing infrastructure.

Basically, this section handles, maintains and repairs the Low Voltage (LV) fixings in the area so:

1. The supply is stable and safe for use.

2. Preventing supply disruptions and faults on the fixings

3. Maximizes the lifespan of the fixings.

This is done via a routine maintenance schedule such as:

1. Patrolling and making visual checks on the span of overhead cables

2. Cleaning/cutting tree trunks which are in the way of overhead cables every three months

3. Numbering/renumbering poles that carry overhead cables

4. Monitoring/Taking load readings from low voltage users

5. Redistributing and splitting the supply from overloaded energy suppliers

6. Tightening contacts on the SAVR fixings

7. Changing old wooden and steel poles with newer concrete poles.

8. Changing old bare aluminum cables with ABC cables for locations that are problematic for the bare cables.

Other jobs include doing operations, switching, isolating and commissioning SAVR fixings to repair faults and maintenance purposes. If needed, this section can request for additional equipment from the Bachok Open Store yard, where most of the stuff is stored and sent back to be scrapped.

(15/4/2010-26/4/2010)

1)A fault is defined as any defects, weakness, inconsistency or non-homogeneity that affects the performance of a cable

2)CAUSES OF CABLE FAULT

There are many reasons why fault occurs. The more common faults are due to the following:

1. Damaged accidentally by external mechanical means.
2. Damage caused as a result of mishandling the cable during initial laying.
3. Poor workmanship in cable jointing.
4. Manufacturer's defects
5. Natural causes due to aging of cable, and
6. Damage caused by movement of soil & erosion.

3)TYPES OF CABLE FAULT

In general fault can be divided into series & shunt types.

1.Series (Open Circuit) Fault

- A fault involving the failure of continuity in either the conductors or cable sheath.

2.Shunt (Short Circuit) Fault

- A fault involving the failure of insulation in the conductor(s).

(5/4/2010-14/4/2010) substation

In the electrical distribution network, a sub-station has many components such as circuit breaker, transformer, and switches, fuses which must be housed properly to ensure continuous and reliable service. According to construction of sub-station, several factors need to be taken for the construction such as location and load demand

There have 4 types of sub-stations in electrical distributions network

Indoor substation

Outdoor substation

Pole-mounted substation (H-pole)

Compact substation

Components in substation

Switchgears – not available in H-pole.

Ring Main Unit – located in PPU only.

Transformers

Protections

Protection Relays and Vacuum Circuit breaker (VCB) – located in PPU only.

Transformer Fuses

Isolating Switch – Located in H-Pole only

Pin Insulator – Located in H-Pole only

Low Voltage Fuses – Located in H-Pole only

Lightning Arresters – Located in H-Pole only

Earthling

Underground Cables

PILC

XLPE

Distribution Boards

Low Voltage Distribution board (LVDB)

Feeder Pillar

Substation work

I. Visual Inspection

Done once per 3 months

Done by seeing, hearing, smelling and feeling the substation and its equipment to see if there is anything wrong with the particular substation

If there were any defect, report to Authorized Person (AP) for corrective maintenance.

II. Routine Maintenance

Done once every 6 months

Take substation data, load reading

Work including cleaning and repairing inside and outside substation such as cut grass, throw rubbish, repairing broken gate and take LV current

Data reading at LVDB.

III. Preventive Maintenance

Done once every 18 months

Full maintenance from top to bottom, involving all of the equipment inside and outside the substation

Done by either the Substation Team or an outside contractor

Among the list of things to do include servicing the LV distribution board (LVDB), servicing the switchgears and servicing the transformers