Light Switches and Dimmers: The Electrician's Guide to Plate Switches, Dimmers, Fan Isolators, and DP Switches

The switches and dimmer category covers more product variations than almost any other in electrical wiring accessories — 1-way, 2-way, intermediate, 1G to 6G plates, leading-edge and intelligent dimming, pull-cord, fan isolator, 20A DP, 45A DP, fused spur, and more. This guide works through each type in the APM range and explains when and where to use them.

1-Way vs 2-Way vs Intermediate Switching

These terms describe the switching circuit, not the number of switches on a plate:

• 1-way: Single switch controls a light — on or off from one location only. Used in cupboards, lofts, and anywhere a second switching point is not needed.
• 2-way: Two switches control one light — the standard for hallways, stairs, and any room with two doorways. Each switch in a 2-way circuit is a "2-way" switch. The vast majority of domestic light switches sold are 2-way, because they function identically to 1-way when only one switch is installed.
• Intermediate: A third switch inserted in the middle of a 2-way circuit — for three-point switching in long corridors, stairs with landings, and open-plan spaces. Each additional switching point beyond two requires one intermediate switch.

10AX Plate Switches — Standard Range

1 Gang

• Knightsbridge 10AX 1G 2-way Switch — White Curved Edge — £1.21 — the most-used switch in domestic wiring. Keep on stock.
• Knightsbridge 10AX 1G 2-way Switch — White Square Edge — £1.99
• Knightsbridge 10AX 1G 2-way Switch — Brushed Chrome — £6.50
• Knightsbridge 10AX 1G 2-way Switch — Brushed Chrome Screwless — £9.00
• Knightsbridge 10AX 1G 2-way Switch — Brushed Chrome Flat Plate — £8.99
• Knightsbridge 10AX 1G 2-way Switch — Polished Chrome Flat Plate — £8.50
• Knightsbridge 10AX 1G 2-way Switch — Matt White Screwless — £9.00
• Knightsbridge 10AX 1G 2-way Switch — Gunmetal — £8.54
• AXIOM 10A 1G 2-way Switch — £1.50
• CED 1G 10A Flat Moulded 2-way Switch — £1.50
• Thrion 1G 2-way 10AX Switch White — £1.60
• MK 10A 1G 2-way Switch White — £3.45
• MK 1G 1-way Switch White — £3.31

1 Gang Intermediate Switch

• Knightsbridge 10AX 1G Intermediate Switch — White — £2.99
• Knightsbridge 10AX 1G Intermediate Switch — Brushed Chrome — £9.99
• Knightsbridge 10AX 1G Intermediate Switch — Matt White Screwless — £10.99
• MK 10A 1G Single 2-way Screwed Intermediate Switch White — £6.49

2 Gang

• Knightsbridge 10AX 2G 2-way Switch — White Curved Edge — £2.99
• Knightsbridge 10AX 2G 2-way Switch — White Square Edge — £3.99
• Knightsbridge 10AX 2G 2-way Switch — Brushed Chrome Flat Plate — £11.79
• Knightsbridge 10AX 2G 2-way Switch — Brushed Chrome Screwless — £11.52
• Knightsbridge 10AX 2G 2-way Switch — Matt White Screwless — £11.62
• Knightsbridge 10AX 2G 2-way Switch — Matt Black Screwless — £10.99
• Knightsbridge 10AX 2G 2-way Switch — Anthracite Screwless — £11.99
• Knightsbridge 10AX 2G 2-way Switch — Polished Chrome — £10.50
• Thrion 10A 2G 2-way Switch White — £2.60
• MK 10A 3G SP 2-way Plateswitch — £8.99

3, 4, and 6 Gang

• Knightsbridge 10AX 3G 2-way Switch — White — £3.99
• Knightsbridge 10AX 3G 2-way Switch — White Square Edge — £4.99
• Knightsbridge 10AX 3G 2-way Switch — Polished Chrome — £12.99
• Knightsbridge 10AX 3G 2-way Switch — Matt White Screwless — £13.99
• Knightsbridge 10AX 4G 2-way Switch (single plate) — White — £7.10
• Knightsbridge 10AX 4G 2-way Switch — White — £5.99
• Knightsbridge 10AX 4G 2-way Switch — Brushed Chrome — £21.99
• Knightsbridge 10AX 6G 2-way Switch — Curved Edge — £7.99

Dimmer Switches

Dimmer selection depends critically on the lamp type being controlled. Two types are in the range:

Leading Edge Dimmers (40–400W)

Leading edge (or conventional phase-cut) dimmers are designed for resistive loads (incandescent and halogen bulbs) and some inductive loads (low-voltage halogen with magnetic transformers). They are not compatible with most LED drivers — leading edge dimmers can cause LED flicker, buzz, and premature driver failure. Only use these with confirmed resistive loads.

• Knightsbridge 1G 2-way 40–400W Leading Edge Dimmer — White — £11.99
• Knightsbridge 2G 2-way 40–400W Leading Edge Dimmer — White — £26.99
• Knightsbridge 2G 2-way 40–400W Leading Edge Dimmer — White Square Edge — £19.99
• Knightsbridge 3G 2-way 40–400W Leading Edge Dimmer — White — £36.99
• Knightsbridge 4G 2-way 60–400W Leading Edge Dimmer — Polished Chrome — £49.99

Intelligent Dimmers (10–200W, LED Compatible)

The Knightsbridge "intelligent" range is a trailing-edge dimmer with soft-start electronics. Rated 10–200W resistive and 5–150W LED. These are the correct choice for LED installations — they produce a smooth, flicker-free dimming curve with compatible LED drivers (check the LED lamp manufacturer's dimmer compatibility list before installing). The 5W minimum load means they also work with a single LED bulb in a circuit.

• Knightsbridge 1G 2-way Intelligent Dimmer (LED) — Brushed Chrome Flat Plate — £17.99
• Knightsbridge 1G 2-way Intelligent Dimmer (LED) — Brushed Chrome Screwless — £22.99
• Knightsbridge 1G 2-way Intelligent Dimmer (LED) — Anthracite Screwless — £21.99
• Knightsbridge 1G 2-way Intelligent Dimmer (LED) — Matt White Screwless — £22.99
• Knightsbridge 1G 2-way Intelligent Dimmer (LED) — Polished Brass Flat Plate — £20.99
• Knightsbridge 2G 2-way Intelligent Dimmer (LED) — Matt White — £32.99
• Knightsbridge 2G 2-way Intelligent Dimmer (LED) — Brushed Chrome Flat Plate — £36.50
• Knightsbridge 2G 2-way Intelligent Dimmer (LED) — Anthracite Screwless — £35.99
• Knightsbridge 2G 2-way Intelligent Dimmer (LED) — Polished Chrome — £29.99
• Knightsbridge 3G 2-way Intelligent Dimmer (LED) — Brushed Chrome Screwless — £48.99
• Knightsbridge 3G 2-way Intelligent Dimmer (LED) — Brushed Chrome Flat Plate — £48.99
• Knightsbridge 3G 2-way Intelligent Dimmer (LED) — Polished Chrome — £44.99
• Knightsbridge 4G 2-way Intelligent Dimmer (LED) — Brushed Chrome Flat Plate — £49.99
• Knightsbridge 2G Dimmer Plate with 2 Matching Dimmer Caps — £2.99 — replacement dimmer caps for standard plates.

Pull Cord Switches

Required in bathrooms and shower rooms where a wall switch cannot be positioned within reach of the basin or shower (unless it is outside the room or in zone 3). Pull cords must be of an insulating material — typically plastic.

• Knightsbridge 10AX 2-way Pull Cord Switch — White — £2.17
• Knightsbridge 10AX 2-way Pull Cord Switch — Matt Black — £13.80
• Knightsbridge 10AX 2-way Pull Cord Switch — Polished Chrome — £13.80
• 45A Pull Cord Switch + Neon — £10.40 — for ceiling-mounted isolation of shower or immersion heater.
• Thrion 10A 1-way Pull Cord Switch White — £1.88

Fan Isolator Switches

A fan isolator is a 3-pole switch that isolates all three terminals of an extractor fan — required for safe maintenance access. They are specced at bathroom extract fan points and kitchen extract fan connections.

• Knightsbridge 10AX Fan Isolator Switch — White — £3.50
• Knightsbridge 10A Fan Isolator Module — White — £7.99
• Knightsbridge 10AX Fan Isolator Switch — Brushed Chrome Screwless — £12.99

20A DP Switches

20A double-pole switches are used for immersion heaters (typically 3kW on a 13A circuit, but some 3kW + storage combos need 20A), shower pumps, and dedicated appliance circuits where a local isolator is required. The switch must be DP to fully isolate both live and neutral.

• Knightsbridge 20A DP Switch — White — £3.30
• Knightsbridge 20A DP Switch with Neon — White — £3.71
• Knightsbridge 20A 1G DP Switch with Neon — White Square Edge — £4.49
• Knightsbridge 20A 1G DP Switch with Neon — Brushed Chrome — £11.99
• Knightsbridge 20A 1G DP Switch with Neon + Flex Outlet — Brushed Chrome — £9.99
• Knightsbridge 20AX 2G SP 2-way Switch IP66 Weatherproof Black — £14.99 — outdoor/garage circuits.

45A DP Switches — Cooker and Shower Isolators

45A DP switches are used as the local isolator for electric cookers, hobs, and electric showers (8–10kW typically). The switch must be positioned to be accessible without reaching across or behind the appliance.

• Knightsbridge 45A DP Switch (2G size) — Red Rocker — £8.69
• Knightsbridge 45A DP Switch with Neon (1G size) — White Rocker — £7.99
• Knightsbridge 45A DP Switch with Neon (2G size) — Brushed Chrome — £15.99

Fused Spurs and Connection Units

A fused spur (or fused connection unit, FCU) provides a switched and fused connection point for fixed appliances — extractor fans, bathroom shaver units, towel rails, wall heaters, and any fixed load that doesn't have its own plug. The internal fuse (typically 3A or 13A) provides overcurrent protection for the appliance flex.

• Knightsbridge 13A Fused Spur Unit — White — £2.99
• Knightsbridge 13A Switched Fused Spur Unit — White — £3.99
• Knightsbridge 13A Switched Fused Spur Unit with Neon — White — £4.34
• Knightsbridge 13A Switched Fused Spur Unit with Neon — White — £4.99
• Knightsbridge 13A Switched Fused Spur Unit with Neon — Polished Chrome — £11.99
• Knightsbridge 13A Switched Fused Spur Unit — Matt Black Screwless — £12.99
• Knightsbridge 13A Switched Fused Spur Unit with Flex Outlet — White — £4.50
• Knightsbridge 13A Switched Fused Spur Unit with Neon — Matt Black Screwless — £14.99
• Knightsbridge 13A Switched Fused Spur Unit with Neon — Polished Chrome — £11.99
• AXIOM 13A Fused Spur Switched with Neon — £2.99
• MK 1G 13A Switched Fused Connection Unit — £11.49
• MK 13A Switch Connection Unit White — £12.99
• MK 13A 1G DP Switched Fused with Neon — £14.99
• MK 1G 13A Connection Unit with Flex Outlet — £8.99
• Thrion 13A Switched Spur Fused Connection Unit with Neon — £5.23

Specialist Switches

Architrave Switches

Narrow profile for fitting to door architraves where there is insufficient space for a standard back box — such as in tight corridor doorways.

• Knightsbridge 10AX 1G 2-way Architrave Switch — £1.80

Kinetic (No-Battery Wireless) Switches

Kinetic switches generate power from the pressing action — no battery, no wiring needed for the switch itself. Used where a switch position cannot be wired conventionally — across a room, on an island unit, or as an additional switching point in a refit without chasing.

• Konect 2 Gang Kinetic Push Switch — Matt White — £21.99
• Konect 2 Gang Kinetic Push Switch — Matt Black — £24.99

Time Delay Switch

Pneumatic time-lag switches provide a timed-off function without electronics — for stairwell lighting, WC fan circuits, and anywhere a light or fan needs to run on for a set period after the switch is released.

• Elkay Pneumatic Time Lag / Time Delay Switch — £22.50

Inline Cord Switches

• Knightsbridge 6A DP Inline Cord Switch — White — £2.49
• Knightsbridge 6A DP Inline Cord Switch — Black — £2.99
• Knightsbridge 5A On/Off Inline Cord Torpedo Table Light Switch — Black — £3.99

Dimmer Type Quick Reference

All switches in stock at our Acton trade counter. For project quantities — a flat, an office fit-out, or a housing development schedule — call ahead and we'll pull the order ready for collection.

APM Plumbing & Electrical | 24 Western Avenue, Acton, London W3 7TZ | 020 8702 8080 | apmi.uk