Fuses

The degaussing coils created quite a surge at switch on,

some fuses were screw-in and therefore round.

Or a mushy grey for quite a few people :-(

and the fun came if you had a German made appliance. Red for earth ......

Its not panto season yet.

No, you can have line to line fault currents (and line to neutral is also "live to live" if one is being a pedant)

and "Fault Current" is not, So why use Fault if you mean Fault Current?

There were screws top and the bottom. The idea was to loop the fusewire round one screw and tighten it, then to do the same with the other screw. Before you say it, yes sometimes the fusewire would break when you tightened the second screw so it was best to leave a suitable amount of slack to allow for this.

Not that long ago. The cables in my flat (not flexes) are mostly in these colours with a warning sticker at the consumer unit saying two colour systems are in use.

No - fan heaters are fitted with 13 amp fuses. Generally each element is 1 Kilowatt.

That's because of the surge when you switch on. Same applies to anything with a motor, such as a vacuum cleaner. You can't just go by the rating plate.

For fixed wiring in a domestic house the colours of red, green and black last for far longer than for cables for appliances....... think the former must have been early 2000s and the latter late 70's/early 80's?

fixed wiring colours changed with the 17th Edition of the Wiring Regs 2008. Flexes in the 15th Edition - 1981

The regs only apply two cases.

A LN or LE short which is a "fault current". This means there is a fault.

Or an overload current. This means an MCB or fuse has been run at more than it's rated value for an extended period of time before tripping/blowing. This is not classed as a fault as the circuit is acting as required.

You would never expect an overload on a lighting circuit but when the CH packs in at an office and everyone fetches a fan heater in and trips the ring circuit then that circuit is behaving as it was designed to do.

Only if it is the real thing. And even them there is very little difference.

And the age of your mother's milkman:-)

Is the counterfeit risk inversely related to amperage then?

I suspect he is talking about when the colours used in *flexes* were red, black, and solid green.

Pretty much. I finally dug out my fairly new copy of the Oxford Dictionary of Electronics and Electrical Engineering, which defines fault current as: "A current that may flow through a circuit or device as a result of a fault, such as a defect in the insulation. The current may take the form of a short circuit, electrical surge, current to earth etc."

I could be pedantic and take issue with the exact wording and the use of the catch-all "etc"., but who am I (a mere 40th generation Angle) to question such a source?

And looking increasingly like they'll forever be renters, will never know what the inside of a DIY store looks like either. Have you noticed all the punters in those places are the wrong side of 50 nowadays?

Perhaps some new guidelines: fit a 10A fuse only for heating appliances; 2A for everything else.