Failed PAT

[SUNRAY]

Earlier today I assisted with some PATing, In the MD's office we found this

plugged into a 4way extention lead, under a pile of blankets AKA dogs bed.

Then this

feeding an ancient metal anglepoise lamp.

Despite the building being only 6 years old he reckons it's worked perfectly for 50 years and doesn't understand why it's failed PAT, however he was aware of the tingle when he touched the lamp.

We offered to remove/dispose for him...

 

[Harry Bloomfield]

feeding an ancient metal anglepoise lamp.

Not seen one of those for 60 years

The plug used a sort of brass split pin to clamp the wires, as you screwed the cover down, it tightened the split pin onto the wires. Clever idea, no tools needed.

 

[SUNRAY]

Not seen one of those for 60 years

The plug used a sort of brass split pin to clamp the wires, as you screwed the cover down, it tightened the split pin onto the wires. Clever idea, no tools needed.

For the befit of the tape; the evidence:

I agree in principle they are a clever idea but in operation I remember them being horrific.
There is no form of cord grip and the copper often fatigued against the edge of the brass, also some pins had very square edges and if overtightened cut into the copper.

 

[Jackrae]

For the befit of the tape; the evicence:
View attachment 249307

There is no form of cord grip ..........

There is a 'form' of cord grip but in the case you show it hasn't been used. There's a pair of bakelite 'hooks' that the individual wires should be routed
through which are intended to take the strain off the wire terminations. Maybe not very effective but in the grand scheme of things at that time, better than nothing.

Remember the 3-way B22 adapters that were very useful for permitting you to iron clothes by the light of a 100watt bulb whilst listening to Workers Playtime on the "wireless" at the same time? Some of the 'better' ones even had switches on them !!

 

[SUNRAY]

There is a 'form' of cord grip but in the case you show it hasn't been used. There's a pair of bakelite 'hooks' that the individual wires should be routed
through which are intended to take the strain off the wire terminations. Maybe not very effective but in the grand scheme of things at that time, better than nothing.

Remember the 3-way B22 adapters that were very useful for permitting you to iron clothes by the light of a 100watt bulb whilst listening to Workers Playtime on the "wireless" at the same time? Some of the 'better' ones even had switches on them !!

Wrist well and truly slapped on your behalf.

It is many years since I've seen these and I remembered them as no cord grip, I don't know if they were all like this or different variations. However I do remember the wires pulling out and getting shocks off the exposed copper on more than one occasion.

 

[BS3036]

Remember the 3-way B22 adapters that were very useful for permitting you to iron clothes by the light of a 100watt bulb whilst listening to Workers Playtime on the "wireless" at the same time? Some of the 'better' ones even had switches on them !!

All of these, and similar monstrosities are available in USA diy stores. I have some shocking photos somewhere on my phone.

 

[plugwash]

Even today ceiling roses and pendant lampholders use hooks on the individual wires rather than a grip on the outer sheath to retain the flex.

 

[Sureitsoff?]

Even today ceiling roses and pendant lampholders use hooks on the individual wires rather than a grip on the outer sheath to retain the flex.

some have collet type cable grips, but at this precise moment I cant think of the manufacturer (but crabtree seems to ring a bell)
found it https://www.tlc-direct.co.uk/Products/CB5855.html

 

[JohnW2]

Even today ceiling roses and pendant lampholders use hooks on the individual wires rather than a grip on the outer sheath to retain the flex.

They do, but a combination of the design, friction and some degree of 'digging into the insulation' seems to be remarkably good at preventing the conductor being 'pulled out' (apologies for poor quality photo). ...

I seem to recall that some older designs had a lump of plastic in the vicinity of the outlet hole, such that the cable sheath was gripped (between it and the cover) when one screwed the cover on, but I haven't seen that design recently.

Kind Regards, John

 

[Harry Bloomfield]

There is no form of cord grip and the copper often fatigued against the edge of the brass, also some pins had very square edges and if overtightened cut into the copper.

There is/was a sort of hook cast into the Bakelite, which forms the cord grip, but it only gripped the cores, not the outer plastic/rubber/cotton or what ever. Who ever fitted that plug, didn't bother with the cord grips.

Back in the day, those plugs were very common.

 

[SUNRAY]

There is/was a sort of hook cast into the Bakelite, which forms the cord grip, but it only gripped the cores, not the outer plastic/rubber/cotton or what ever. Who ever fitted that plug, didn't bother with the cord grips.

Back in the day, those plugs were very common.

Jackrae has pointed this out, I'll freely admit I didn't look/notice when I took the pic. I haven't handled one for years but recall the wires pulling out to be a regular problem, more to do with the copper failing than anything else.

 

[ericmark]

Is an extension lead an appliance? OK testing and testing of in service electricial equipment but again is an extension lead equipment.

 

[crystal ball]

Is an extension lead an appliance? OK testing and testing of in service electricial equipment but again is an extension lead equipment.

Pretty sure they are dealt with at length in the COP

 

[SUNRAY]

Is an extension lead an appliance? OK testing and testing of in service electricial equipment but again is an extension lead equipment.

I'd say yes it is an appliance, when I go out on a job the extention leads are as important as the power tools or amplifiers etc and I do a form of PAT every time I use some my extention leads; IR, resistance and visual.

 

[conny]

Is an extension lead an appliance? OK testing and testing of in service electricial equipment but again is an extension lead equipment.

I would not class it as an appliance per se but as it is portable, and most PAT kits come with the equipment for testing them, then I would certainly class them as part of the 'equipment' for test.