brightspark
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here's some info on the characteristics of a cartridge fuse http://www.pat-testing-training.net/articles/fuse-operation-characteristics.php
That’s really interesting.here's some info on the characteristics of a cartridge fuse http://www.pat-testing-training.net/articles/fuse-operation-characteristics.php
I've seen that a few times PAT sticker on a plug with the card still there and I have no idea how many I have removed from cards from plugs in newly built racks.It also highlights the reason why the card with the wiring instructions should always be removed from the plug before use.
Thats an old wives tail.I remember being told by an old guy that fuses "age" and as they get older the current required for them to blow increases so much so that a really old fuse will happily pass double it's rated current without blowing.
Is this true or an "old wives tale" because I've never found anything on the internet about fuses "ageing" ?
they get weaker as get older especialy if there run close to there limit . the copper anneals and is discoloured it looses the tin coating and u can tellI remember being told by an old guy that fuses "age" and as they get older the current required for them to blow increases so much so that a really old fuse will happily pass double it's rated current without blowing.
Is this true or an "old wives tale" because I've never found anything on the internet about fuses "ageing" ?
I think it's more that an older fuse will have lasted longer as it has a wider tolerance than a fuse with a narrow tolerance that is likely to blow sooner.I remember being told by an old guy that fuses "age" and as they get older the current required for them to blow increases so much so that a really old fuse will happily pass double it's rated current without blowing.
Is this true or an "old wives tale" because I've never found anything on the internet about fuses "ageing" ?
Not that I would EVER trust a company to PAT test anything after I visited my Son's school to look at one of their computers and found the desk was without power. I looked underneath to see a 13 amp plug in the extention strip and wondered where it went to. I followed it to the next desk where there was another 13 amp plug on the end of the wire by the side of another plug strip! BOTH plugs had a PAT test label for that very day!
The children had been using these leads to daisy chain the desks which meant that they were handling LIVE plugs and they had been made by the 'IT teacher'.
I showed the headmistress and she nearly fainted when I explained the danger AND the fact that a company thought it was ok to label them safe.
Needless to say I also told her not to pay the company and to have a word with the teacher, the word was DISMISSAL for gross negligence.
I always do my own PAT testing, ALWAYS.
I also often wonder how some of the 13 amp plugs I see, ever pass safety tests. Self tappers securing the covers which can come away and expose the terminals and fuse pins that move so much that it spreads the connectors and causes overheating. Only ever use a top quality plug like an MK.
they get weaker as get older especially if there run close to there limit . the copper anneals and is discoloured it looses the tin coating and u can tell
I always assumed this was common knowledge. .....
It might be common knowledge to you but to someone else it'll be a complete mystery, I happen to be good at welding & sheet metal work for example but I'm hopeless in the kitchen, but to someone who's good at cooking they'll wonder why I can't get all the bits of a meal to finish at the same time because to them that is basic knowledge.... I'm sure there is stuff you aren't good at.I always assumed this was common knowledge. .....
what else would you expect them to test ?Unless things have changed all they could really test on a computer was the power lead.
Yep. Think I posted this before, but in a previous job I was horrified to discover that the admin folks had let the electrician into the server room (around twenty 42U racks with 32A PDUs in each) unsupervised.PAT testing is a joke. Unless things have changed all they could really test on a computer was the power lead.
And yes I love mk plugs - I have a large collection of them!