Armoured Cable (SWA)
Underground Power to Gate and Garden (2026)

What armoured cable is

An armoured cable is built in layers. In the middle are the copper cores, each with its own coloured insulation. Around them is a bedding layer, then a layer of galvanised steel wires wound round the cable, then a tough outer sheath, usually black. The steel layer is the armour: it gives the cable mechanical protection where it is buried, clipped along a wall or run where it could be knocked.

Ordinary house wiring is not built for the ground. Suruhanjaya Tenaga's domestic wiring guideline matches the insulation to the job in its Jadual 8.6: single-insulated conductors in conduit or trunking, double-insulated cable for surface runs on tray or clips, and armoured PVC-insulated conductors for underground cable. That is the short answer to the most common question on this subject: indoor wiring pulled through a garden hose is not an underground cable.

Armoured cable is sold by the number of cores (commonly two, three or four) and the conductor size. Which one a job needs depends on the supply (single-phase or three-phase), the load at the far end and the distance, which is the electrician's calculation, not a shop-counter guess.

Jobs that need power underground

• Autogate. The motor and control box at the gate need a mains supply from the house; quotes usually list the wiring and the cable trench as separate lines, and our autogate repair guide covers faults on the gate side.
• Garden and fence lights. A run of lights along a long garden or a boundary wall.
• Pond and fountain pumps. A pump at the far end of the garden that runs every day.
• Outbuildings. A store, a workshop, a guardhouse or a garden room with its own lights and sockets.
• Outdoor EV charger. A wall box on a pillar or a car porch that is not next to the house wall.
• Outdoor sockets far from the house. A point at the bottom of the garden for tools or a pressure washer.

For a socket close to the house, cable along the wall in conduit is usually simpler; our outdoor power socket guide covers that case. This page is about the runs that cross open ground, a driveway or a lawn.

Armoured cable or cable in conduit?

There are two common ways to get power across the ground, and a third that is better avoided.

A sleeve under a driveway is worth putting in even when the cable is armoured: it lets the cable be replaced without breaking up the paving, and a spare sleeve beside it costs little when the trench is already open.

What the wiring guideline says

• Underground cable is armoured. Jadual 8.6 of the guideline lists armoured PVC-insulated conductors for underground cable.
• RCD protection. The guideline's RCD table, following Regulation 36 of the Electricity Regulations 1994, sets no more than 30 mA for socket-outlet circuits and no more than 10 mA for places likely to be wet, with fence and garden lights, pools and water heater circuits as its examples.
• Outdoor lamps. Lights installed outside a house must be weatherproof and waterproof.
• Its own circuit where the load needs it. Motors above a set size, water heaters and similar loads are connected on their own circuit; a pond pump or a large gate motor is a question for the electrician, not something to spur off the nearest socket.

The guideline is written for registered wiremen and contractors, and new mains wiring outdoors is work for them. Earthing the far end properly is part of the same job; our earthing and earth rod guide explains how earthing is tested.

Cable size and long runs

The further power travels, the more voltage is lost along the cable. On a short run to a porch light this does not matter. On a long run to a pump, a gate motor or an EV charger at the far end of a bungalow lot, a cable that is too thin delivers less voltage than the equipment expects: motors run hot and struggle to start, chargers slow down, and protective devices may trip.

The guideline includes a voltage-drop table for multicore armoured cables (its Lampiran VI) in millivolts per ampere per metre, which is what an electrician uses with the load and the distance to choose a conductor size. The practical points for an owner are simple:

• Tell the electrician what is at the far end now, and what may be added later (a second light circuit, a charger, a socket).
• Measure or estimate the real route, not the straight line: around the porch, along the wall, under the driveway.
• A cable one size larger costs a little more now and far less than digging the trench again.
• Ask for the cable type, number of cores and size to be written on the quote.

Planning the trench and route

1. Mark the route on a sketch of the lot, from the distribution board to the far end, and keep it with the house documents.
2. Keep away from where posts, trees, pergola footings and future extensions will go.
3. Avoid running alongside water and drain pipes in the same trench where the layout allows, and keep clear of the gas pipe if there is one.
4. Lay warning tape in the trench above the cable so the next person who digs knows what is below.
5. Bring the cable up into the building or enclosure through a protected entry, not bare up the face of a wall.
6. Plan it with landscaping or driveway work: the trench is cheapest when the ground is already open.

The guideline does not, in the sections quoted here, give a burial depth for a domestic garden run, so agree the depth and the protection over the cable with the electrician before the trench is dug, and have it written on the quote.

Glands, joints and earthing

Where an armoured cable enters a box, a gland grips the outer sheath and clamps the steel armour. The armour must be terminated in that gland and earthed, otherwise the steel layer is a long piece of unearthed metal wrapped round live conductors. At the far end, the cable goes into a weatherproof isolator, a sealed junction box or the equipment's own enclosure.

• Use glands made for armoured cable and the right size, with a shroud over the outdoor end.
• Avoid buried joints. If a joint cannot be avoided, it should be a proper jointing kit made for underground use, not tape.
• Fit an isolator at the far end so the gate motor, pump or outbuilding can be switched off locally for maintenance.
• Test the circuit after installation: insulation, earth continuity and the RCD trip.

Power to an autogate

An autogate has two electrical halves. The mains supply from the house to the control box is live mains work; the board, the operator, the remotes and the safety devices beyond it are the gate technician's side. Our autogate motor replacement guide explains why that split matters when a motor is changed, and the autogate power cut guide covers the backup battery that keeps the gate working when the supply fails.

When a new gate is installed, the supply cable and any low-voltage cable for sensors and accessories should go in at the same time, in separate runs. Adding a cable after the driveway is finished means breaking it up again.

Common problems with buried supplies

If the house wiring is old, have the board and earthing looked at before adding a long outdoor circuit; our electrical safety inspection guide covers what is checked.

What it costs

Underground power is priced on the route: the distance, whether the trench crosses lawn, tiles or concrete, the cable size, and what is at the far end. These figures are ClickBina's published prices for related work (indicative 2026, Klang Valley).

A long armoured run across a large lot, a sleeve under an existing driveway, or a separate circuit from the board is priced after the route has been walked. For the pond itself, see the koi pond cost guide.

How ClickBina can help

WhatsApp us your job details for a quote: your area, house type, what needs power, the rough distance from the DB box, and what the route crosses (garden, tiles, driveway). ClickBina is an experienced KL & Selangor contractor that coordinates the trenching, reinstatement and finishing around a job like this. We reply within the hour, and the price we agree is a flat price with no hidden charges. For a fault on an existing buried supply, a repair inspection is RM180, deducted from the repair bill if you go ahead.

Sources & methodology

• Suruhanjaya Tenaga — Garis Panduan Pendawaian Elektrik Pepasangan Domestik — Jadual 8.6 (armoured PVC conductors for underground cable), Jadual 7.2 RCD sensitivity (Regulation 36), para 9.1(f)(iii) outdoor lamps, Lampiran VI voltage drop for multicore armoured cables.
• ClickBina outdoor power socket guide — outdoor point, long run and koi pond wiring prices.
• ClickBina autogate cost guide — autogate wiring, control board and ground works prices.
• ClickBina autogate motor replacement and power cut guides — the mains and low-voltage sides of an autogate.

How we estimated prices: every RM figure on this page is quoted unchanged from the ClickBina guides named above; they are indicative Klang Valley ranges for 2026.