How to use a surge protector
Updated: October 2026
The bar is in your hand, the television is waiting, and the surge lamp is a small green dot you have not looked at yet. How to use a surge protector, in a UK home, is a short sequence: one wall socket, a load you can add up, a lamp you can read, and a stop when the case smells hot. The listings were sorted on the [surge protector comparison](/hub/diy-supplies/surge-protector). Peter F. used maker instructions and UK safety guidance, not a laboratory test, on 15 October 2026. A purchase through our amazon.co.uk links can earn a commission at no extra cost to you.
The bar is in your hand, the television is waiting, and the surge lamp is a small green dot you have not looked at yet.
The bar is in your hand, the television is waiting, and the surge lamp is a small green dot you have not looked at yet. How to use a surge protector, in a UK home, is a short sequence: one wall socket, a load you can add up, a lamp you can read, and a stop when the case smells hot. The listings were sorted on the surge protector comparison. Peter F. used maker instructions and UK safety guidance, not a laboratory test, on 15 October 2026. A purchase through our amazon.co.uk links can earn a commission at no extra cost to you.
Our top picks
| Badge | Product | Indicator | Load | Switching | Note | Price | Offer |
|---|---|---|---|---|---|---|---|
| Best overall |  Masterplug Masterplug 4-gang 2 m surge lead | Power and surge LEDs | 13 A | Unswitched | 9.2 | about £8.70 | View offer |
| Preis-Tipp |  Masterplug Masterplug 3-socket surge adaptor | Surge lamp | 13 A | Per socket | 7.9 | about £8.25 | View offer |
| Alternative |  HANNELORE HANNELORE 7-gang metal surge strip | Not stated | 2,500 W stated | Master switch | 5.7 | about £29.95 | View offer |
On this page
Plug it into the wall, not into another lead
Put the strip into a BS 1363 wall socket, one lead per socket. Electrical Safety First tells you not to plug one extension into another, and not to exceed the current rating. Look at the plug and the cable before you insert them. A cracked moulding, a bent pin, or a nick in the flex is a reason to stop.
Philex’s surge-lead leaflet keeps the same domestic limits: one lead, 220–250 V, no daisy-chain. If the room only works as a chain of bars, a registered electrician should fit more sockets.
Add up the load before you fill the sockets
Every socket on the strip shares the one 13 A fuse in the plug. At 240 V that is 3,120 W on paper. Stay nearer 3,000 W, and stop at any lower figure the maker prints. The HANNELORE metal strip in this comparison tells you not to exceed 2,500 W, so a full row of seven sockets is not an invitation to fill them with heat.
London Fire Brigade says a kettle, a toaster, an iron, or a microwave wants a 13 A fuse of its own, and those appliances should not share one extension. The television, a soundbar, a console, and a phone charger usually fit together, well under 13 A.
Read the surge indicator
A lit surge lamp means the protection the maker describes is still in circuit. A power lamp only means the sockets have mains. They are not the same light on strips that have both, such as the Masterplug SRG4210N, which lists power and surge LEDs. If the sockets still work and the surge lamp is dark, Philex tells you the protection is used up and the lead should be replaced. Masterplug’s manual says the same about a failed surge neon: replace the lead.
There is no fixed life in UK law that says you must swap the strip every three years. A maker may suggest a few years or a change after a bad storm. That is their instruction, not a statute. Whether a joule figure was printed is on the surge protector buying guide.
When you stop and who you call
Unplug the strip, at the wall, if the plastic smells hot, if it buzzes, if it pops, or if you see scorch marks. One reviewer of the SE UKASE tower reported a hot-plastic smell and treated it as a fire risk. That is a reason to send the unit back, not to reset a breaker and try again.
If switching the strip off trips the house RCD, leave it unplugged. One HANNELORE reviewer described that trip repeating. That trip is a fault for a qualified electrician, not a setting on the bar. The same call applies if the wall socket is warm. The set behind a screen is surge protector for a TV.
Common questions
Where do I plug the strip in?
Into one BS 1363 wall socket, and not into another extension. Check the plug pins and the cable first. If the room already depends on a chain of leads, stop adding bars and ask a registered electrician about more sockets. Masterplug’s £1,000 connected-equipment warranty, where the listing states it, is void if leads are daisy-chained.
What should the indicator be doing?
The surge lamp should be lit while the strip is in use. On a lead with two lamps, the power lamp only shows that mains is present. The surge lamp is the one that tracks the protection. If you cannot tell which is which from the leaflet, compare the listing’s wording for power and surge before you rely on a single glowing dot.
The sockets work and the protected light is off. Now what?
Stop treating the strip as surge protection and replace the lead. Philex and Masterplug both say a dead surge indicator with live sockets means the protection is finished. The television coming on does not reverse that. Unplug it and use another strip, or the wall, until the replacement arrives.
Can I plug a kettle or a heater into it?
Put the kettle, heater, toaster, iron, or microwave in the wall socket. They can each demand most or all of a 13 A circuit. Sharing them with a television on one strip is the overload London Fire Brigade warns against. The HANNELORE’s own 2,500 W cap is a further limit on that metal bar, even before you reach 13 A.
Can I plug a second extension into this one?
No. Electrical Safety First forbids daisy-chaining extensions. A second lead does not give you another 13 A. On Masterplug’s surge warranty, daisy-chaining also voids the connected-equipment cover where that warranty applies. If you are short of sockets, the fix is another wall outlet, fitted properly, not a longer chain behind the sofa.
The strip is warm, buzzing, or smells of plastic. Do I reset it?
Unplug it at the wall and leave it out. Do not reset the consumer unit and plug the same unit back in to see if it holds. A pop on first connection, a buzz, or a hot-plastic smell is a failed lead. Return it. If the wall socket itself is hot or marked, that circuit is for a qualified electrician before any new strip goes there.
Switching it off trips the house RCD. Is that a setting?
It is not a setting you should clear and ignore. Unplug the strip. If the RCD trips again when that load is switched, stop using the circuit for the strip and ask a qualified electrician to find the fault. One review of the HANNELORE metal strip described repeated trips. Another strip in the same socket is not the repair.
Related pages
Sources
Public UK sources on surge protective devices, BS 1363 plugs, and extension leads. Listing prices and star counts are from the amazon.co.uk extracts kept for this comparison on 15 October 2026. Prices move.
- IET Wiring Matters, Surge Protective Devices, November 2023 (retrieved 15 October 2026)
- IET consumer guidance on SPDs (retrieved 15 October 2026)
- IET BS 7671 edition checker (retrieved 15 October 2026)
- Electrical Safety First, extension leads (retrieved 15 October 2026)
- Plugs and Sockets etc. (Safety) Regulations 1994 (retrieved 15 October 2026)
- BEAMA extension-lead checklist (retrieved 15 October 2026)
- Masterplug SRG4 sheet (retrieved 15 October 2026)
- Masterplug surge warranty (retrieved 15 October 2026)