Surface mount sockets

[Dave Plowman (News)]

Great fun. Can be done easily DIY with care and no special tools. Just takes longer. Think it's in the FAQ, how to.

[Dave Plowman (News)]

My guess is any wholesaler who stocks it will cut it. It's true the seals and glands are expensive at about 3 quid a go - but then so is say chrome plated copper pipe, and people will pay for that where it can be seen. And plenty of sockets cost a great deal.

With care, you can terminate it without special tools - it just takes longer. And is quite fun.

My view is a competent DIYer who works with copper pipe and has reasonable understanding of electrics will be fine with it. Getting it might be the biggest problem. IMHO, the end result done neatly looks better than any alternative over brick or old wood, etc. After a short while copper blends into them so well.

[Dave Osborne]

Just to be clear on this point, you absolutely *must* megger each piece of pyro/micc after you have potted it but before it is terminated. It is

*not* suitable for DIY if you don't have access to a 500V insulation tester.

[js.b1]

Ebay is probably the best bet for Pyro or MICC...

- Glands can be had cheaply

- Cable can be had by the metre (3 core 1.5mm is =A33.25) or offcut (21m is =A359)

QVSdirect had cut-length, glands etc a few months back but nothing now.

I would suggest a visual pilot.

1) Stick the light and socket on the wall with double sided tape - photograph from within the room somewhere re "context" & print off in colour. 2) Buy 8mm copper tube, stick the 8mm copper tube to the wall leading to each wiring accessory - photograph from within the room somewhere re "context" & print off in colour.

Leave the pictures on the coffee table for a day and you will then decide which you prefer. You may like it, but then go off it. It is like the kitchen sockets with 2G+1G+2G all jammed against one another, or spaced apart, there is an aesthetics issue which is best sorted out before you start fixing things to wall.

[Dave Plowman (News)]

With respect, bollocks. I'm assuming you're using new cable - not something stored in the rain for years. There simply is no need in practice if you work carefully.

BTW, what do you consider the difference between 'potting' and 'terminated'?

[dennis]

Potting is stripping, putting the resin in, and putting the end on.

Terminating is connecting it up.

[Tim Watts]

No, I agree with Dave O. PVC if new and visibly undamaged can reasonably be assumed to have good insulation.

You cannot assume that, in particular, a piece of pyro bought from ebay, or an offcut from the wholesaler, hasn't been subjected to damp.

Also, as a DIYer, I wouldn't feel happy unless I could megger the thing

3 months down the line. Potting is possible to get wrong, letting in moisture later.

Noone said you couldn't DIY a tester for this purpose - it is after all only a 500V DC test. Given pyro can cope with 1000V tests, the simplest (and slightly dangerous, but not if you're careful) tester would be a mains driven voltage doubler (couple of diodes and capacitors), limiting resistor and an micro-ammeter.

Cheers

Tim

[Dave Plowman (News)]

Pyro doesn't use resin.

[Dave Plowman (News)]

Water damaged pyro is pretty obvious to the experienced - the MI isn't a powder anymore. It also progresses through the cable pretty slowly - so normal stripping will sort most.

And an ordinary decent DVM will show clearly if you have this condition.

As regards water getting in later - take care making the termination and it won't. Unless the cable gets badly damaged - which is a different matter.

[Dave Osborne]

What Tim says. Although I would advocate the use of a 16th approved (i.e. minimum 1mA test current) 500V insulation tester.

With an off-cut of pyro of unknown provenance (or known to have been hanging around for a while), you need to Megger it before you pot it. If it doesn't Megger before you pot it, there's no point in potting it at all. You can try alternately cutting each end back until it Meggers and/or you can put it in the oven for a couple of hours to suck the moisture out of the ends. When the offcut Megger's OK, then you can install it and pot it, then (because you can f*sk-up potting quite easily, particularly if you don't have the right tools), you need to Megger it again (before terminating the ends to the rest of the installation) to be completely confident you've potted it properly. This way when you come to do a final Megger of the work done, you can be sure that if it fails, it will not be due to moisture in the pyro or a badly-potted pyro-end, it will be something else. This discipline can save an awful lot of heartache, time and cost later.

DaveyOz

[Dave Plowman (News)]

I think you're making a meal out of it. Of course some thick sparkie who doesn't give a toss can f**k it up - in the same way as so many of them don't tighten terminal screws properly. But with care a competent DIYer should be ok by following the instructions in the FAQ. I've made many thousands of terminations without problems. And although I do have the special tools I have on occasion made new ones without. I'd also say through experience that you have no more need to megger the circuit than a PVC TW&E one. If you take care. A DVM will show up any likely fault. Of course if you have a megger then use it. But taking care is a better way.

[Dave Osborne]

I thought you were an ex-BBC Film sound engineer? In what context have you "made many thousands of [pyro/micc] terminations"? You are in a very small minority if you have. Pray tell.

[Tim Watts]

You may ask why test any new installation?

[dennis]

What's the putty if not resin?

[Dave Plowman (News)]

You thought wrong.

Commercial greenhouses. The BBC pay was so poor I had a second job.

[Dave Plowman (News)]

I'd ask how many times faults are found.

[Dave Plowman (News)]

Putty. Resin sets.

[Tim Watts]

In my personal experience, once in the last 2 years. Broken neutral in a ring. Would never have noticed if I hadn't followed the standard testing regime.

So, categorically, I say, without any hestistation, new work *should* be tested. Perhaps *inside* a house with all new components and T+E, one could skip the IR test (I've never seen that anything than offscale), but there, continuity and RCD tests are very wise.

You may argue that in the case above, a simple multimeter would have been good enough for the end-end ring test that would indicate a broken conductor. Yes it would. Even the diagnostic search was done with a binary search rather than trying to be clever with conductor resistances.

But, what if the RCD was out of spec? That does happen and it's rather harder to test those. Pyro, especially if it is terminated for the first time by an inexperienced person, AFAIC *must* be tested, if if the test is gerry rigged. Pyro has a known failure case (mositure) that is considerably more likely to occur compared to leakage in a T+E installation.

With respect, I don't care if *you've* done thousands of pyro terminations - that means you have a feel for what's right. Newbies don't. I wouldn't either, so they and I ought to be testing the stuff. And IMHO *we* (uk.d-i-y) ought to be promoting good practises :) Not saying "bollocks" to someone who is doing so...

Cheers

Tim

[Bob Eager]

You'll be an expert on potting then! .-)

I'll get me coat...

[Dave Plowman (News)]

You'd have found that with any continuity testing device - like a two quid DVM.

I'm very much *not* against testing. Just pointing out that for a small DIY job you don't need to rush out and get a megger as suggested.

IMHO the vast majority of likely faults on a simple installation will be shown up with a DVM. And relying on expensive test equipment to guard against poor workmanship is the wrong way round. For example, if you changed a plug, would you feel it necessary to have that device PAT (tested)? It's the same sort of thing.

Damp pyro will show up on a DVM. I've checked this. Have you? However, it's nothing like as common as some suggest. If bought from a reputable seller, just terminating it will remove any ingress of moisture. Stored outside or in damp conditions for a considerable time would be a different matter.

And what would be the result of leaking pyro? A fire? Explosion? Do you have your own installation regularly tested for faults that may develop after installation? Seems to me these are equally as likely as installation ones.

I dislike someone saying 'you mustn't do this' unless there is a very good safety reason. With pyro in particular there isn't.

Basically, I'm saying don't let the pros who are terrified by pyro put you off having a go DIY wise if it's what you want. Just practice first and take care. As it says in the FAQ.