Home | CSR |

Home > Business > For Housing Developers & Electrical Contractors > TNB Electricity System

TNB Electricity System

VoltagesVoltages

The transmission voltage networks are 500kV, 275kV and 132kV, whilst the distribution voltages11kV and 400/230 volts. However, in the case of certain parts of Johor & Perak the distribution voalso include 22kV and 6.6kV.

Supply FrequencySupply Frequency

The supply frequency is 50Hz ± 1%.

Earthing SystemEarthing System

High Voltage and Extra High Voltage

3 phase configurationSolidly earthed or impedance earthedOverhead lines and underground cable are used extensively for high and extra high voltag

Low Voltage 400/230V

3 phase 4 wire systemNeutral point solidly earthed mixture of overhead lines, underground cables and aerial insuMixture of overhead lines, underground cables and aerial insulated cables

Short Circuit RatingsShort Circuit Ratings

As a guide, the maximum fault levels for the various voltage systems are as follows. All equipmebe installed and connected to TNB supply must comply with the stated short circuit ratings:

System Short circuit rating for 3s

500 kV 50 kA

275 kV 40 kA

132 kV 31.5 kA

66 kV 20 kA

33 kV 25 kA

22 kV 20 kA

11 kV 20 kA

6.6 kV 20 kA

Business

Energy Savings at Work

Power Quality

Tenaga Link

Malaysian Grid Code

Meter Replacement

Programme

For Commercial

For Industrial

For Housing Developers &

Electrical Contractors

TNB Electricity System

SLA Between TNB and Housing

Developers

How to Register as a TNB

Electrical Contractor

Discounts, Rebates & Offers

Charges and Penalties

Residential Customers Business Customers Investors Suppliers About TNB

Terms & Conditions | Staff Webmail | Electric Eyes | Sitemap© 2014 Tenaga Nasional Berhad (200866-W). All Rights Reserved

Follow us on:

400/230 V 31.5 kA

Act, Regulation and CodeAct, Regulation and Code

The electricity supply and installation practice in Peninsular Malaysia are governed by the followin

Electricity Supply Act 1990 - Act 4471. Licensee Supply Regulations 19902. Electricity Regulations, 19943. Occupational, Safety & Health Act 19944. Malaysian Standard MS IEC 60364 Electrical Installation of Buildings5.

Supply Voltage OptionsSupply Voltage Options

Supply may be provided at any of the declared voltages:

275 kV, 132 kV, 33 kV, 22 kV*, 11 kV, 6.6 kV* and 400/ 230 V.

Generally, supplies to domestic premises are given at single phase 2-wire or three phase 4-wire. actual supply voltage provided depends on the magnitude of the individual applicant’s load requi

Low Voltage

Single-phase, two-wire, 240 V, up to 12 kVA maximum demand1. Three-phase, four-wire, 415 V, up to 45 kVA maximum demand2. Three-phase, four-wire, C.T. metered, 400/230 V, up to 1000 kVA maximum demand3.

Medium Voltage & High Voltage

Three-phase, three-wire and 11 kV for load of 1,000 kVA maximum demand and above1. Three-phase, three-wire, 22 kV or 33 kV for load of 5,000 kVA maximum demand and abo2. Three-phase, three-wire, 66 kV, 132 kV and 275 kV for exceptionally large load of above 2demand

3.

It should be noted that voltages other than the above classifcations couldn’t be provided by TNB.consumers can make their own transformation arrangements where necessary.