Do cartridge fuses deteriorate with age?

[G6Tanuki]

That looks like a "Duraplug" power-strip - I recognise the incoming-flex-loop. And yes the live bus-bar-to-fuse clip connection does look to have suffered heating as well as the fuse.

I too don't really trust 'consumer' multi-way power-strips - I've got a couple of professional ones here [Lexor Dis-Boards, or Olson] which are metal-cased, bulky but reliable. They use traditional glass 1.5-inch fuses in decent panel-mount holders, too.

[kellymarie]

I still have several of those durable 4 way sockets mine must be 40 odd years old by now mine lost the shutters over the live parts when they melted after running a 2Kw heater on it along with a big power supply and a light its still going strong but probably wouldn't pass moder health and safety inspection

[paulsherwin]

Originally Posted by Radio Wrangler

That sounds like the fuse wire itself going crystalline.... a bit like a dry solder joint. Its resistance goes up.

Fuse wire does deteriorate over time, made worse by being repeatedly heated. If it's subjected to current very close to its rating it will indeed get very hot and will take a while to blow. BS1362 fuses are really intended to protect against dramatic overcurrents caused by things like short circuits.

As others have said, the BS1363 plug doesn't cope well with prolonged loads close to the 13A rating. I think plug in electric fires were derated somewhat to allow for this at some stage - 3kW or even 3.5kW heaters were quite common in the 60s and 70s, but are never found today.

As a general rule, it's not a good idea to power a high current appliance such as a heater through an extension socket.

[Radio Wrangler]

Originally Posted by paulsherwin

As a general rule, it's not a good idea to power a high current appliance such as a heater through an extension socket.

I have a hefty (2.5mm squared arctic) extension cable and the rubber single 13A socket on the end of it is not of impressive quality. It gets used for high power loads (Welders, big power tools, big tool transformer) - things whose own cables run warm to the touch.

I think next time I replace it I'll either fit an MK masterseal socket with a cable gland, or else I bite the bullet and change everything to 16A connectors.

David

[bionicmerlin]

As most of the plugs these days are made of cheep plastic ,repeatedly plugging and unplugging loosens the fuse contacts. You might get away with a light load but on high power items it will often cause overheating.
Always use a Bakelite plug for high load items making sure the fuse contacts are tight and so are the screws. Andy

[emeritus]

I did wonder if a reason for circa 2kW appliances becoming common was so that the same product could be sold throughout mainland Europe, where 10A - rated sockets are common (reflecting the "condition hot" 10A appliance connector), higher-rated sockets being less common.