4-way extension with trunked flex

joolsmy · Jul 7, 2017

I was chatting with a PAT tester who mentioned that he would fail 4-way extensions where the flex had been trunked and the client was using them with appliances drawing 13 amps. His reasoning was that the trunked flex should be de-rated. Would you agree with this?

westward10 · Jul 7, 2017

What do you mean by trunked.

westward10 · Jul 7, 2017

Most four way extension lead ends have instructions for connecting to a 13A plug top. I will always note this on an EICR if they are hard wired to the mains supply.

[ElectriciansForums.net] 4-way extension with trunked flex

Squid · Jul 7, 2017

westward10 said:
What do you mean by trunked.

Cable run in trunking from socket to final location I'd assume.

westward10 · Jul 7, 2017

I misread your first post, a four way extension should be wired using 1.25 flex (13A) or 1.5 flex (16A). If it is contained within trunking he maybe theoretically correct depending on the cable csa but personally I think he is pushing the boundaries a bit far.

Pete999 · Jul 7, 2017

joolsmy said:
I was chatting with a PAT tester who mentioned that he would fail 4-way extensions where the flex had been trunked and the client was using them with appliances drawing 13 amps. His reasoning was that the trunked flex should be de-rated. Would you agree with this?

This PATester bit simple is he? what idiot is running an extension lead in trunking, wait a sec has someone hard wired this 4 way extension?

joolsmy · Jul 7, 2017

By trunking I think he meant a plastic u-shaped channel with a snap-on lid. I assume a 13 amp plug would be in use and the "trunking" added to provide some extra protection to the 1.25 flex.

Pete999 · Jul 7, 2017

joolsmy said:
I was chatting with a PAT tester who mentioned that he would fail 4-way extensions where the flex had been trunked and the client was using them with appliances drawing 13 amps. His reasoning was that the trunked flex should be de-rated. Would you agree with this?

Might want to derate the OCPD in the plug top, feeding the 4 way extension, if he is that much of a Jobsworth.

Squid · Jul 7, 2017

Pete999 said:
This PATester bit simple is he? what idiot is running an extension lead in trunking, wait a sec has someone hard wired this 4 way extension?

You'll be surprised as trunking gets used as "cable management" in some offices......

westward10 · Jul 7, 2017

I have seen this but it isn't that common and I wouldn't worry too much as long as the correct fuse is fitted at the plug top. Extension leads in offices are rarely going to achieve their maximum rating.