Plug top on 1.5 t&e

dacons · Jun 1, 2016

So was sent to move some sockets today on a big office display anyway I spotted all the display light strips on extension leads made up of a 13amp plug top some had lower fuses others didn't but the plug top where on 1.5 t&e so I've now been asked to do a report on this and other bits so before a trawl the regs is there a reg that anyone knows that applies to this.

Risteard · Jun 1, 2016

Plug tops are not within the remit of BS 7671, but the arrangement is prohibited. BS 1363 is the relevant Standard.

Richard Burns · Jun 1, 2016

A BS 1363 plug is designed to accept a flexible cable, because they are liable to be moved about and so the cable must be able to handle the movement.
A twin and earth cable is not deigned for frequent movement and the conductors are likely to crack if they are continually moved.
As said it will not come under BS7671 but it is an inappropriate choice of cable for the external influences to which it will be subjected and it is not a cable for which the plug is designed.
The fuses being different is just laziness but in this case the fusing will not generally be relevant unless the wrong fuse has been fitted to a plug, e.g. if a 10A extension lead has a 13A fuse.

dacons · Jun 1, 2016

Ok cool also what about a plug on a flex that feeds a socket in a wall so flex unclipped down a mdf wall cavity into a metal clad back box to feed a flush socket the flex is 1.5 and about 5m long

Richard Burns · Jun 1, 2016

Poor practice but just about acceptable, the weight of the unsupported cable will be pulling on the plug and unless the cable grip is very firm could cause strain on the plug terminations and the cable to become loose, also the weight of the cable could pull the plug partially from the socket and cause a poor connection.

Adam W · Jun 1, 2016

There used to be a photograph in the II&TEE code of practice which expressly forbid putting a plug on a bit of T&E.

If the two things you've mentioned are both in the same office it may be worth them getting you to do a full EICR to see what other corners have been cut. As Richard says running a fixed socket in flex and plugging it in somewhere is just about technically acceptable although nobody who calls them self an electrician would do it - it's something inexperienced DIYers do.

Marvo · Jun 1, 2016

T&E has solid cores, the termination points in plug tops are designed for stranded. T&E is designed as an installation cable, solid conductor cores are likely to break if it's used as a trailing lead, also it's likely it's bending radius limitations will be exceeded. I'd say it would be much safer the other way around ie if stranded cable was used for installation (assuming it was ferruled/lugged at terminations) rather than T&E used as trailing cables.