Conduit

[69er]

Hi all

I often use pvc rigid conduit to run my cables on the outside of a house-99% of the time its 10mm earth but occasionally its a new ring. Question is do I have to fit the inspection tees and elbows with the screws facing outwards? I ask because there are no join anywhere in the cables and I think it doesn't look as neat when you see the inspection plates. Is anyone really going to need to open up the inspection plate and look at a piece of cable? Thanks

 

[Lectrician]

If you are talking inspection elbows/tees - I would bin them.

They are fine for running ELV telephones/alarms etc, but are pure madness for real elec.

Use circ boxes with lids. Use gasgets if outside, and make sure you ave a drain hole at the bottom of the conduit system.

You MUST have inspection access, to comply with the recs, between all bends amounting to 180deg. (two 90, or one 90 and two 45 for example). This is assuming you pull your own bends, and are not using manufactured bends for everything - that just looks awfull! . Also, every so often on straight runs (from memory, can't remember the actual distance, but I always go for 3m, your going to use a coupler, so why not a through box!).

2x2.5 T+E isn't really suited to 20mm PVC conduit either.

 

[Lectrician]

Proof readin that, The punctuation and grammer and speeling is ****e.

Sorry, but early drinking.

 

[69er]

Thanks for the reply. I didn't realise that inspection tees etc are that crap. They are all our electrical supplier does - can you recommend a brand/product to use instead? [/quote]Do you mean that between the bends there has to be an inspection point or just at one of the bends? Pull your own bends? Excuse the ignorance The lengths of conduit I use are 3m so I use a straight coupler normally. What advantage is there of using a through box? The size of conduit I use is 25mm. Still too small? Sure I read somewhere that the cable must not take up more than 60% of internal space? Thanks

 

[69er]

Sorry about the quote thing - thought I had figured how to do it but evidently not!

 

[Lectrician]

Pull your own bends, meaning with a bending spring. Similar to bending copper plumbing pipe.

Circular conduit boxes are my prefered method for tees, bends etc.

Through boxes instead of couplers aid pulling in cables and altering at later dates.

25m is ok for 2 x 2.5 T+E. 20mm would be tight, especially on bends.

 

[69er]

Thanks for that. I see what you mean by pulling your own bends - I assume you use metal conduit? As I use pvc I have to use the manufacturers bends etc - I do my best to make sure it looks good. If I use circular through boxes etc I assume I will still have to fit them with the screws showing? I have seen some "speed" fittings for conduit and they don't have any access plates etc?

 

[Adam_151]

You bend pvc conduit with a bending spring , you do metal conduit with a bending machine (would love to someone bend metal conduit by hand, and if they did, they would knacker their kneecaps )

You just put the spring in the pvc conduit, add a gentle heat (not too much or it'll go pear shaped), heard of someone who just rubs it with a cloth a bit to warm it, and then bend it over your knee or re-inforced cable drum, you have to bend it a bit too far becuase it springs back a bit.

Best way to learn is to try it, you'll mess up a few bends (I still haven't got the knack of it - I only use it in a DIY capacity though, so haven't had much practice)

 

[69er]

Didint realise you could bend it etc - will give it a go. Now I know what Lectrician means by neater finish - thanks for the tip!

 

[andy]

Didint realise you could bend it etc - will give it a go. Now I know what Lectrician means by neater finish - thanks for the tip!

make sure to use the spring, or itll go tits up

 

[69er]

I knew that ! Just had visions of spending time trying to bend the pipe and it going **** up! Only got 22mm pipe spring - reckon it will do?

 

[Adam_151]

I knew that ! Just had visions of spending time trying to bend the pipe and it going **** up! Only got 22mm pipe spring - reckon it will do?

Doubt it'll fit in (oh-err ), I got a spring for 20mm PVC conduit for £4 from the local B&Q warehouse store...so its not going to break the bank

 

[dwain dibley]

Proof readin that, The punctuation and grammer and speeling is s***te.

Sorry, but early drinking.

Is that a capital T after a comma? Shurrly not!

 

[andy]

I knew that ! Just had visions of spending time trying to bend the pipe and it going **** up! Only got 22mm pipe spring - reckon it will do?

Doubt it'll fit in (oh-err ), I got a spring for 20mm PVC conduit for £4 from the local B&Q warehouse store...so its not going to break the bank

you tryin to say a 22mm spring will not fit in a 25mm hole?!

do they not teach you kids maths these days?!

 

[Adam_151]

thought he said 20mm