PAT / ITEE Testing. IEC lead fuses

[JohnW2]

The C13 IEC is rated at 10A. If the cable was 0.75mm I would put a 5A fuse in the plug, if the cable was 1.00mm I would put a 10A in if I had one, or a 5A.

It’s very unlikely any equipment that has a C13 fitted to it would draw anywhere near 5A, the only issue would be if the equipment had a high inrush current which could blow a lower amperage fuse, such as a vacuum cleaner.

I rather doubt that an inrush current would last long enough to blow a BS 1362 (that had adequate rating for the running current), even if that inrush current were appreciably more than the fuse's rating.

 

[plugwash]

It’s very unlikely any equipment that has a C13 fitted to it would draw anywhere near 5A,

I built a workstation and the Intel workstation case came with a 1KW power supply that had a C13 inlet. The power supply was the modern type with a "universal voltage" input, so even at 230V it could potentially draw around 5A and under undervoltage conditions it could draw substantially omre.

In practice that is unlikely, the PSU would have to be maxed out (which would never happen with the hardware in the box) and undervoltage itself is fairly unlikely, but I nevertheless put a sticker on it telling people to use a 1.0mm IEC cord.

Higher chance in an AV environment (a theatre for example) where the use of daisy chaining IEC appliances and the use of IEC splitters are used.

Some lighting dimmers also use IEC outlets. This leads to people making adapter cables. The same is true of some UPS's and datacenter equipment but that is at least likely to be touched less often and thus the adapters less likely to "escape".

Apologies for my cynicism and to generalise, but in my experience PAT testers don't check the fuse, the cable condition or whether the CE mark on something is genuine,

There seems to be a persistent myth about "china export" marks. There may be some correlation between bad typography of the CE mark and bad quaility of the equipment, but there is plenty of dodgy equipment with properly printed CE marks and plenty of perfectly fine equipment with misprinted marks.

and most companies that procure PAT testing services are box ticking and want it done as cheaply and quickly as possible

 

[hllns]

In practice that is unlikely, the PSU would have to be maxed out (which would never happen with the hardware in the box) and undervoltage itself is fairly unlikely, but I nevertheless put a sticker on it telling people to use a 1.0mm IEC cord.

Around 1kW does seem to be the cut-off for some manufacturers fitting C16 inlets rather than C14, 550W PSU for the switch I've checked has C14 fitted, 1050W PSU comes with C16 (that I've never personally seen leads for in 0.75mm), they seem to be designing it so less knowledgeable persons are less likely to get it wrong.

Some lighting dimmers also use IEC outlets. This leads to people making adapter cables. The same is true of some UPS's and datacenter equipment but that is at least likely to be touched less often and thus the adapters less likely to "escape".

UPS and data centre use does bring up the interesting scenario that there may be no lower capacity cartridge fuses at all in the circuit, all that could be protecting your C13 outlet may be a 16A circuit breaker on the UPS/PDU itself.