Recent content by steveb

522.5.3 may be from the 17th however 522-05-03 existed in the 16th Edition Regualtion 522-05-03 from the 16th Editition states "Materials liable to cause mutual or individual deteriation or hazardous degradation shall not be placed in contact with each other."

Many thanks for the reply peca27. I guess I was a bit naive in expecting the full package. I'll get back to the builder and fingers crossed, calculations will match installation. Once again many thanks for taking the time to give such a comprehensive response. All the best Steve

In early September 06 we decided to have two ground floor rooms knocked into one . I decided to enlist the services of a local builder who was a member of the federation of master builder. I looked through yellow pages and found a builder who was a member and he carried out the work in...

You can do as secure says using 2.5mm sq provided adequate mechanical protection is provided, otherwise 4mm sq.

No you should not carry out 3 and 4 of your proposal. Ideally you need to identify where the cable supplying the wall light is fed from and disconnect at source rendering the whole cable dead. If you cannot achieve this I would personally terminate the end of the cable into a flush...

It could be a loose connection, however something else to keep in mind is that the contacts within the switch itself deterioate with age and can eventually cause the insulation and the condutor to heat up and cause subsequent damage to the cable at the point of connection. It is possible...

I agree, but I'm not sure if further derating of cable is necessary in this particular example. I would have thought that if insulation derating value is applied then this will be sufficient :?:

Yes Mandate my house is included in those 1000's. When I looked at the loading compared with cable size there was sufficient capacity in the cable to allow for derating. This probably applies to many dwellings. If the cable was fully loaded then there is a potential problem with over heating...

Gangs is the number of switches. eg in your passage you may have a 2 gang switch, one gang controlling your passage light and the other gang controlling your landing light. Ways - your landing switch is usually controlled from the passage switch and the landing switch, this is known as 2 way...

The Surveyor is partly correct. If you install cables in thermal insulation you need to derate the cable. eg if a cable is capable of carrying 10amps you have to derate the cable when designing the circuit and only load the cable with say 5amps. Im not sure of the exact derating factors but the...

I had a similar problem in my house. The light fittings on my particular circuit were basic ceiling roses with flex to lamp holder. What happened in my case was that the heat off the lamp had caused the flex insulation within the lamp holder to crumble, leaving bare wires which subsequently...

The 45amp mcb quoted is for the older types of Wylex consumer units. It is designed as an upgrade from the old rewirable type of fuses and is not suitable for the NN range of consumer unit. The NN consumer unit requires NB type mcb's. I'm pretty sure these are only available up to 40amps