Plugs, sockets, and what each one will carry

Can a 13 A plug run 13 A all day?

On paper, yes. BS 1363 rates the plug and socket at 13 A and doesn't give a lower continuous figure. The 1995 edition's temperature-rise test, as quoted on the IET's forum, ran at 14 A until the temperature stopped climbing, for up to eight hours. The 2016 revision of BS 1363-2 added an optional EV marking, which means extra cyclic sustained-load tests rather than a different design, because people had started charging cars from ordinary sockets and some of the sockets had cooked.

In practice the rating assumes a clean, tight socket, and a show's 13 A outlets are rarely that. An urn, a heater or a kettle rack pulling 13 A for a whole get-in through a socket with a few thousand insertions behind it is where you find the brown plastic. Anything that needs more than about 10 A for hours belongs on a 16 A blue.

A drum is a 13 A lead only when it's unwound. Coiled, the turns heat each other and the label gives a much lower figure (check the drum; there's no standard number). The volt-drop page has the watts a loom dissipates at full current, which is what's heating the middle of the coil.

The round industrial connector is BS EN IEC 60309-2, which replaced BS 4343. Crews call it a commando, after MK's brand, or a Ceeform, after CEE 17, the European spec it grew out of. Three things tell you what one is. The colour says the voltage band. The size says the current: 16, 32, 63 and 125 A bodies are different diameters and don't mate. The earth position, read as an hour on a clock face with the socket's main keyway at six o'clock, says the voltage and frequency again, mechanically.

• IP44 and IP67. IP44 is splash-proof, with a sprung flap on the socket. IP67 has a gasket and a screw collar, and it's only IP67 with the collar done up or the cap on. The pins and keyway are the same, so the two will usually mate, and the pair is then only as sealed as its weaker half. I haven't found a manufacturer statement on mixed pairs either way.
• 63 A and 125 A: switch off first. Interlocked sockets (IEC 60309-4) won't release the plug while the outlet is live, and won't switch on without a plug in. Some 63 and 125 A connectors also carry a pilot contact that drops the load before the main pins part. Pulling one under load without either draws an arc that can weld the contacts and burn whoever is holding the plug.

The "IEC lead" is a family of appliance couplers in IEC 60320-1, every one rated at 250 V and numbered on a single rule: the connector on the cable has an odd number and the inlet on the kit is one higher. A C13 goes into a C14, a C19 into a C20. The connector is always the female half and the inlet the male, because the end that carries power has to be the one with shrouded contacts.

• The kettle lead isn't a C13. A kettle's inlet gets hot, so it's a C16, and the lead is a C15, rated for 120 °C pins against the C13's 70 °C. The C15 has a groove that lets it into a C14 as well; the C16 has a ridge that keeps a C13 out. So the C15 from the urn will run your monitor, and the C13 from the monitor won't go into the urn, which is the right way round.
• That's the rule all the shapes follow. A better connector enters a lesser inlet and never the reverse: hotter into cooler, earthed into unearthed. A C13 fits a C18 (an earthed lead on double-insulated kit is harmless), and a C17 won't fit a C14 (an unearthed lead on kit that needs its earth isn't). The build checks every pair in the table against that rule.
• C7/C8, the figure-8, is unearthed at 2.5 A. There's a polarised version with one flat side, which isn't in the standard, and an ordinary C7 goes into a polarised C8 inlet anyway. Don't rely on it for polarity.
• C19/C20 is the 16 A one, and turns up where a C13's 10 A runs out: big amps, LED processors, servers and rack PDUs.
• Locking. An IEC Lock connector grips the earth pin of any standard C14 or C20 inlet and releases with a red slider, so it needs nothing special on the kit. Volex's V-Lock locks with a pin into a notch in a matching V-Lock inlet, so it only locks into kit fitted with one; in an ordinary inlet it's an ordinary connector.

Neutrik's powerCON is the locking mains connector on most lighting and a fair bit of audio. The blue one is power in, the grey one power out, keyed so you can't mate two supplies. That much has stayed the same since the original. What hasn't is the rating and whether you may unplug it live, and the generations look almost identical.

• The newer blue is rated lower than the old one. The original was 20 A under EN 61984, a connector standard, and its datasheet says it "must not be connected or disconnected under load or live". The XX series that replaced it is certified as an appliance coupler under EN 60320-1, at 16 A. That standard is what lets Neutrik claim circuit-breaking capability, and the claim only holds when both the cable connector and the chassis connector are XX.
• So a mixed chain is the worse of both. An original cable into an XX inlet, or the reverse, gives you 16 A (the XX half's rating) and no breaking capacity (the original half's). Treat any chain you haven't checked end to end as that. The part number is the giveaway: XX parts have XX in it.
• TRUE1 is a separate family. It's the weatherproof one, 16 A with breaking capacity and IP65 mated (IP65/IP67 on the current part), and it doesn't mate with blue or grey; the adaptor leads that exist are the evidence. It uses one connector in two genders rather than two keyings, and the female cable connector is the live end. TRUE1 TOP replaced the first TRUE1 and the two are fully compatible; NAC3F-TRUE1-S is now replacing TRUE1 TOP.
• The 32 A powerCON is a bigger body, so it doesn't mate with the 16 or 20 A parts. Neutrik describe it as non-standardised and without breaking capacity, and it takes 2.5 to 6 mm² conductors.

Generator feeds and main distros use single-pole connectors, one per conductor, five for a three-phase supply with neutral. In the UK that's Powerlock, developed by Litton Veam in the mid-1990s and now an ITT Cannon brand, with compatible parts from other makers. It comes in 400 A and 660 A versions, for up to 1000 V AC. A 400 A three-phase set is 277 kVA, which is 277 kW only at unity power factor. Generators are rated in kVA, and why that number is bigger than the one your kit adds up to is on the power factor and generators page.

• The genders are backwards on purpose. The source has the male pin, shrouded so a finger won't reach it, and the load end has the female. That's the reverse of most power connectors and it's why a dead-looking pin on a Powerlock tail is still not something to hold.
• Colour and keying are separate. The insulators follow the local wiring colours, and each conductor is also keyed mechanically, so a European blue neutral won't mate with a North American blue phase.
• Sequencing. Sequential mating panels make earth and neutral before the phases and break them after. Neither the colours nor the caps do that; the panel does.
• Camlock is the American cousin: single-pole, around 400 A, a twist cam to lock it, without Powerlock's finger-proof shrouds and sequencing. It's not interchangeable, and a hire company's Camlock tails won't go into a UK Powerlock distro.
• Socapex is the other multi-circuit connector you'll meet, six 230 V circuits on one 19-pin plug. Its pinout and what length costs you are on the multipin looms page.

• BS 7909:2023+A1:2024, Temporary electrical systems for entertainment and related purposes, is the code of practice for the management, design, setting up and operation of a show's power. It replaced BS 7909:2011. It's the usual way an event shows it has met the wiring regulations, and it expects a named person responsible for the system and someone competent to design and sign it off.
• BS 7671:2018+A4:2026, the wiring regulations, has two Part 7 sections that apply. Section 711 covers temporary installations for exhibitions, shows and stands. Section 740 covers temporary installations for structures, amusement devices and booths at fairgrounds, amusement parks and circuses. Amendment 4 was published on 15 April 2026 and Amendment 3 withdrawn six months later. I haven't read A4's text of either section.
• RCDs. Socket-outlets up to 32 A get additional protection by a 30 mA RCD under the general rules, and the exhibitions section extends 30 mA protection to every final circuit for lighting and socket-outlets up to 32 A, emergency lighting excepted (that's IEC 60364-7-711's wording, which section 711 is based on). An RCD protects people from earth faults. It does nothing for an overloaded plug, which is the breaker's and the fuse's job.

• A 16 A blue feeding 13 A sockets with no fuse or breaker between. The 16 A breaker upstream lets anything up to 16 A through, so the 13 A socket (or the four of them on a home-made splitter) is protected by nothing between 13 and 16 A. Splitters with a 13 A fuse or MCB in them exist and cost very little more.
• A 13 A plug feeding a 16 A blue socket. The plug fuse does protect it, so this one is safer than it looks, but the socket now offers 2,990 W while looking like 3,680. Plug a 16 A load in and the plug runs over its rating until the fuse decides, which at a bit over double can take minutes. Label it.
• A powerCON chain counted by the fixture, not the first link. See the table above, then check the manual.
• A 16 A chain hung off a 32 A outlet through an adaptor with no 16 A protection. Same problem as the 13 A splitter, one size up.
• Old and new powerCON in one chain, then unplugged live because "powerCON can do that now". The XX half can; the original half can't, and the arc pits the contacts of both.
• A coiled drum at full load. If the thermal cut-out trips, the coil is overheating: unwind the drum fully or use a bigger cable.
• A male-to-male lead, usually made up to back-feed a strip or a PDU. Its free end has live, bare pins. Take it out of service and cut it up.

Put in a load, per unit, and how many of them share the connector. It works out the current per phase and lists every connector on that supply with the headroom left. Amber is above 80 %, a common planning margin for loads that run all show; BS 7671 doesn't set a flat figure, the designer does. Power factor turns watts into amps: at 0.8 the same watts draw a quarter more current, and the power factor page has why.

• Neutrik datasheets, downloaded from neutrik.com on 3 November 2026: NAC3FCA and NAC3MPA-1 (the original powerCON, 20 A to EN 61984, the no-breaking-capacity warning), NAC3FXXA-W-S and NAC3MPXXA (powerCON XX, 16 A to EN 60320-1, breaking capability only with XX parts), NAC3FX-W, NAC3FX-W-TOP and NAC3F-TRUE1-S (TRUE1, its successors and their compatibility), and NAC3FC-HC (32 A).
• MENNEKES, Protective conductor contact clock position and plug colours, reproducing IEC 60309-2:2023 table 210, for the earth positions. The voltage-band colours are from the summary of IEC 60309 on Wikipedia, which agrees with the manufacturer catalogues I checked. IEC 60309 itself is paywalled and I haven't read it.
• BS 1363 and BS 1362, worked from summaries (Wikipedia's BS 1363 article for the fuse ratings, colours and BS 1362 pre-arcing times, BSI's catalogue for the current editions). BEAMA's fuse-to-cord pairing and the 14 A temperature-rise test are as quoted on the IET Engineering Communities forum, not read from the standards.
• BS 7671 Table 4F3A, flexible cords, as reproduced in cable makers' catalogues; the IET's announcement of Amendment 4 (15 January 2026); and IEC 60364-7-711 for the 30 mA wording.
• BS 7909:2023+A1:2024, BSI catalogue entry, for the edition and scope.
• Powerlock: Wikipedia's article and the ITT Veam material it cites, for the ratings, history, reversed genders, keying and sequencing.
• Van Damme's TRUE1 cable listing and LEX Products' grey-to-TRUE1 adaptor, for TRUE1 not mating with blue/grey powerCON.
• IEC 60320: Schurter's appliance-coupler knowledge pages and white paper for the ratings and pin-temperature classes, and Wikipedia's IEC 60320 article for which connector enters which inlet, the polarised C7 and the 2-2 interconnection sheets. IEC Lock from UK distributors' listings (Canford and others); V-Lock from Volex and Schurter. UK lead fusing from retailers' listings and the IET forum. The standard itself is paywalled and I haven't read it.

Assembled 3 November 2026 with AI assistance. The arithmetic is checked at build time (the kilowatts, the fuse-to-cord pairing against Table 4F3A, the colour of every IEC 60309 row against its voltage band, the clock positions within each pin count, and the powerCON ratings) and those checks catch a transcription error but can't catch a wrong source. The Neutrik figures are read from current datasheets; the British and IEC standards are paywalled and are worked from reproductions, so check anything you're relying on against your own copy. None of this is a design. A temporary installation needs designing, inspecting and signing off by a competent person under BS 7909.

Companion pages: cable voltage drop for what a long feed loses and how hot it gets, multipin looms for Socapex, power factor and generators for kVA, kW and sizing the thing at the end of the Powerlock, and LED processor and power lines for how many panels go on a 16 A circuit.