Conduit for earth & PIR

[burntwire]

Hi,
If a socket and lighting circuit are using the conduit as a cpc what code if any would this be on a PIR, I was thinking 2 however at the time of installation I am guessing it was acceptable,

Also if diffusers are missing from lights would this just be a note on installation or a code, do the lamps on fluorescents have to have diffusers in a public place ? or is it just good practice ?

Oh and one more, metal switch plate covers which are old rely on the metal screw for the earth, they have no provision for a cable to be terminated directly. Is this a code ?

Thanks

BW

 

[martinxxxxxx]

Yes the first PIR can be difficult without someone to help with advice. Perhaps you could take a series of photographs and have the whole thing checked by the forum members. You would need to include the schedules as well.

 

[ChrisRogers]

what's wrong with having the conduit as the CPC?

 

[burntwire]

Nothing is wrong with it,

Although it does pose a problem should someone cut it and change it by adding plastic etc could it be a problem ?

This is why I am asking

Sorry cant get any photos for a couple of weeks

 

[burntwire]

It seems I have been a bit lazy, reg 543.2 - 5, says it perfectly fine to use conduit as cpc as long as each point is connected by a seperate protective conductor, I guess the metal switch plates are a code 2 then as this can not be done with no cpc terminal

 

[mfarrow]

Someone could also rip down the consumer unit off the wall and replace it with a big junction box.

Remember though that this is an inspection of the present installation - nobody can predict what idiots will do in the future.

The only thing which would be wrong is if any of the joints are concealed or not accessible for inspection.

 

[flameport]

If a socket and lighting circuit are using the conduit as a cpc what code if any would this be on a PIR,

No code, providing the conduit is in good condition, which is why inspection is so important, not just testing.

Also if diffusers are missing from lights would this just be a note on installation or a code

Probably not required, however in some instances diffusers or covers would be needed, such as over a production line where a broken tube would result in glass particles falling into whatever was being made.

Oh and one more, metal switch plate covers which are old rely on the metal screw for the earth, they have no provision for a cable to be terminated directly. Is this a code ?

No, provided the connection between the faceplate and backbox is satisfactory when the plate is secured.

 

[ban-all-sheds]

If a socket and lighting circuit are using the conduit as a cpc

Do you mean that you've got two circuits in the same conduit, sharing the same conduit as their cpcs?

 

[mfarrow]

No, provided the connection between the faceplate and backbox is satisfactory when the plate is secured.

Unless it's part of the conduit:

543.2.7 Where the protective conductor is formed by conduit, trunking, ducting or the metal sheath and/or armour of a cable, the earthing terminal of each accessory shall be connected by a separate protective conductor to an earthing terminal incorporated in the associated box or other enclosure

Why do you reckon this is? Nothing worse than a Code 4?

 

[burntwire]

no they have seperate conduits

 

[holmslaw]

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[holmslaw]

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[bernardgreen]

The proper test sends a current of 25A? through the conduit, this could cause heating and cable damage at any bad joint.

Which would also mean a voltage drop across the bad joint which could be detected by measuring voltages (relative to the start of the conduit) along the conduit route.

 

[Paul_C]

Do you mean that you've got two circuits in the same conduit, sharing the same conduit as their cpcs?

Nothing wrong with that.

Or with using a single earth conductor for two circuits with a PVC conduit installation, so long as it is sized for the largest protective device.

 

[holmslaw]

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