The layout behind the switches and sockets: what a wireman plans and why each circuit is separate.
A Malaysian home's wiring runs from the TNB meter to a main switch and earth-leakage protection in the DB box, then splits into final circuits: lighting and fan circuits in thinner cable, socket circuits in ring or radial form, and a dedicated circuit for each aircon, water heater and cooker. The Suruhanjaya Tenaga guideline sets the minimum cable sizes and how much floor area a socket circuit may serve. Wiring is fixed electrical work for a registered wireman, not DIY. A new wiring point is listed at RM120 – RM250 (indicative 2026, Klang Valley). A site visit is RM150, waived if you go ahead.
Every home installation follows the same path. TNB's cable arrives at the cut-out and meter, which belong to the supplier. From there the owner's installation begins: a main switch, earth-leakage protection (RCCBs), and a row of breakers (MCBs), each feeding one final circuit that runs out to lights, sockets or a fixed appliance. The whole arrangement is laid out in the Suruhanjaya Tenaga (ST) domestic wiring guideline, whose stated purpose is to be a concise guide for competent persons, electrical contractors and consulting engineers doing wiring work.
This page explains the layout so you can understand a quotation or a renovation drawing. It is not a set of instructions: connecting, altering and testing circuits is work for a registered wireman.
The ST guideline sets the minimum copper conductor size for each kind of final circuit:
| Circuit | Minimum conductor (ST) | What it feeds |
|---|---|---|
| Lighting and fan circuits | 1.5 mm² | Ceiling lights, downlights, fans, light switches |
| 13A socket outlet circuits | 2.5 mm² | General sockets in rooms, kitchen and hall |
| Special power circuits | 4–6 mm² | Air-conditioners, water heaters, cookers, motors and pumps |
A typical terrace or condo has a few lighting circuits split by floor or zone, several socket circuits, and one dedicated circuit per aircon and per water heater. The DB box size guide shows how those circuits translate into ways on the board.
A lighting circuit runs from its breaker to the first light point, then on from point to point around the zone. At each light, a switch cable drops down the wall to the switch. The ST guideline's example drawings show the basic arrangements: one light point controlled by one one-way switch, two points on one switch, two points on two separate switches, one point controlled from two places with two-way switches, and three points with two-way and intermediate switches.
That is why moving a light is rarely "just extending a wire": the new position needs its own feed from the loop and its own switch cable. The light switch types guide explains one-way, two-way and intermediate switching in more detail.
Sockets are wired either as a ring, where the cable leaves the breaker, visits each socket and returns to the breaker, or as a radial, which runs out and ends at the last socket. The ST guideline limits the floor area each type may serve for general socket circuits in homes:
| Circuit type | Breaker rating (A) | Minimum copper conductor | Largest floor area served |
|---|---|---|---|
| Ring | 30 or 32 A | 2.5 mm² | 100 m² |
| Radial | 30 or 32 A | 4.0 mm² | 75 m² |
| Radial | 20 A | 2.5 mm² | 50 m² |
In practice this means a larger home has several socket circuits, split by floor or zone, rather than one circuit for the whole house. Where sockets should go, and how near the sink or hob they may sit, is covered in the socket placement rules guide.
High, long-running loads each get their own circuit from the board, in the larger special-power cable. Each split aircon has one; an oven or induction hob has one. The electric water heater circuit is treated with extra care: the ST guideline says it must be permanently connected to a 20A or 32A breaker or fuse with an RCD of not more than 10mA. A dedicated appliance circuit is listed from RM400 in the power points guide.
Every circuit carries a protective (earth) conductor alongside the live and neutral, bonding metal parts of fittings and appliances back to the main earth. It is what lets an RCCB detect a fault and cut the supply. The colours of live, neutral and earth follow a standard code; the wiring colour code guide explains the current colours and the old ones still found in older houses.
The ST example layouts group circuits under two RCCBs after the main switch: socket circuits under a 30mA device, where people handle appliances, and lighting, fan and aircon circuits under a 100mA device. The water heater has its own 10mA protection. Grouping like this means a leaking kettle trips the sockets, not the lights, so you are not left in the dark while finding the fault.
During a renovation, the routes are set at first fix, before plaster and ceilings close. The first fix and second fix guide explains that order and what to check before the walls are closed.
Getting the layout wrong does not usually fail on day one. It fails years later as an overloaded socket circuit, a heater without the right protection, or an earth that was never connected. Wiring must be done, tested and certified by a competent person registered with ST, who measures insulation, continuity, polarity and earth before the installation is energised. The electrician services guide explains the wireman grades and what the paperwork should show. For older homes with original wiring, the house rewiring cost guide lists the signs that a rewire is due.
These are the published ClickBina indicative ranges (2026, Klang Valley):
| Job | Indicative price | Source |
|---|---|---|
| New wiring point / lighting circuit | RM120 – RM250 per point | Home lighting design guide |
| Concealed (chased-in) socket | RM200 – RM400 | Power points guide |
| Dedicated appliance circuit | from RM400 | Power points guide |
| Rewire a kitchen with dedicated circuits | RM2,000 – RM5,000 | First fix and second fix guide |
| Partial rewiring / add points (per area or per circuit) | from RM1,500 | House rewiring cost guide |
| Full rewire, single-storey terrace house | RM8,000 – RM15,000 | House rewiring cost guide |
WhatsApp us your job details for a quote — we reply within the hour.
💬 WhatsApp for a quotePrices depend on the number of points, how far they are from the board, concealed or surface wiring, and whether walls and ceilings are already open for a renovation.
WhatsApp us your job details for a quote: the property type, and whether you need new points, a partial or full rewire, or wiring as part of a renovation. ClickBina is an experienced KL & Selangor contractor for whole-house refurbishment and trade coordination, so the wiring routes are planned with the walls, ceilings, carpentry and paint that follow. We reply within the hour, and the price agreed is a flat price with no hidden charges. A site visit is RM150, waived if you go ahead.
Methodology: technical figures follow the ST guideline; prices are ClickBina indicative 2026 Klang Valley ranges from the guide named beside each.
WhatsApp us your job details for a quote — we reply within the hour.
💬 WhatsApp for a quoteTell us what you need — we reply within the hour.