Severe oddness!

[Reid Malenfant]

I have just noticed something that is now bugging me severely :eyebrows:

This is hifi related, but it's also related to how old your house is & who the heck wired it up :scratch:

I have a total of three Belkin PF40 power conditioners which I was lucky to get at a good price. Having done some investigating it was found that a few of these units were wired up incorrectly & a couple of the little icons on the display may show a fault when there isn't one.....

Well I thought two of the three I purchased were wired incorrectly as the little wiring & earth icons showed a cross in the display, rather than a tick as they should do :rolleyes:

Well now I'm not so sure!

You see I was using these previously on my P600 Power Plant which delivers balanced mains, so the fact that the icons said things were wrong didn't matter. But the P600 died a few days ago & now they are wired to the output of a Power Plant Premier & all of a sudden both the wiring & earth icons have a tick in them :scratch:

The PPP rebuilds the mains so the output is the same as the input only cleaner, it doesn't invert or do daft things. Now as I myself wired in the dedicated spur to this room (so I know it's 100% correct) that can only mean that the socket I originally plugged the PF40s into was wired incorrectly :eek:

I'm going to test that idea out tomorrow, I hope to god I'm wrong, but I think some numpty has got live & neutral about face in the back of the socket in the wall. If that's the case & I think it could be, it means that the fuse in any mains plug that is in that socket will actually be in the neutral lead & won't blow if it's shorted to earth as neutral should be damn near at earth potential.

It also means that with no fuse in the real live lead there is a real potential for causing a fire if real live shorts to earth :eek:

I think I'm going to check every socket in the house tomorrow :rolleyes:


Be safe, if you moved into a house & you are the second owner please get things checked out thoroughly! Your life & the lives of your family could depend on it :exactly:

I have lived here 30 years & might have only just discovered this :doh:

[Marco]

Have you considered that your house could be haunted? :eek:

Marco.

[Reid Malenfant]

:rfl:

It probably is, after all it is about 150 years old & I know at least one person passed away here...

I just don't believe in all that tbh... Once you are dead then that's it imo :eyebrows:

I don't know of a local Ghostbusters either :D

[Roy S]

How often should your house be rewired?

Just had a new consumer unit cos I had an electric shower fitted but not sure of the vintage of the wiring (no bakelite light switches so that's a result)

[Reid Malenfant]

How often should your house be rewired?
I'm not sure if there is any set period, just as long as it's up to the latest specifications & using twin & earth cable in the rings you should be ok.

You should have at least two rings if you live in a house, upstairs & down, each will either have it's own fuse or mechanical circuit breaker in the consumer unit.

All fuses here as it's 30+ years old.

The cable doesn't tend to decay as it's not moved about & PVC is pretty resilient anyway, just look at extension cables on wind up drums :)

[stewart]

get one of these, CP501

http://www.pat-training.co.uk/socket_testers.htm

(just in case you were going to take every socket off the wall)

[Reid Malenfant]

get one of these, CP501

http://www.pat-training.co.uk/socket_testers.htm

(just in case you were going to take every socket off the wall)
Good point & link Stewart :) Nice one if anyone wants to test their own sockets.

I don't need one myself as I'll use a multimeter to check things as I know how to. It just never occured to me that I might need to :rolleyes: Call me a numpty if you like, I guess assumption could well be the mother of all f*ck ups :doh:

[anthonyTD]

hi Mark,
You make a very good point, we all take for granted that our sockets are wired up correctly, its well worth the effort to check them, you can get an inexpensive plug in tester [ some are yellow in colour and just look like a normal plug]that will tell you in an instant if things are correct or not.
Good luck with your investigation Mark, let us know your findings.:)
Anthony,TD...

[Reid Malenfant]

Good luck with your investigation Mark, let us know your findings.:)
Will do :) I actually went to check it earlier with a LEN block but the battery in the multimeter needs recharging :eyebrows:

No rush, I won't be using the socket for a while so a few hours won't make a difference.

[DaveK]

We've been in our house since it was built in 1967. We got it as first reserve when the original intended buyer, a professional house electrician, withdrew at almost the last minute when they found out that the baby they were expecting was actually twins :stalks: and that news pushed their budget one baby too far. I mention this because he'd done a deal with the house builder for a price reduction if he did all the wiring himself so I know the property was properly wired up and in accordance with the regulations as they stood then.
About 4 years ago my wife decided she wanted a completely new kitchen so I ripped out the perfectly good units :steam: and got friends and contacts to do the installation. This involved installing many more power points so a certified sparks was brought in - OUCH!!! :eek: . What he had to do before he could recertify the house was bl**dy incredible and bust my new kitchen budget by over £a few hundred so be warned. What might appear to be a relatively small job to the average guy may cost an arm and a leg just to get the necessary certificate, without which I believe the property is unsaleable.
The laughable thing is that the sparks told me that these regs do not apply to DIY rewiring done by the house owner - they have (had?) a relatively free hand to do what they want with the wiring in their own property - don't make a lot of sense to me.
You have been warned :lol: . The regulations are changed by our friends in Brussels at least once a year so the above may well be out of date now, so check before you start.
Dave.

[MartinT]

These are very cheap and do the job:

http://www.delightful-uk.com/ekmps/shops/kennedyelec/images/socket-tester-electrical-mains-plug-in-polarity-safety-1141-p.jpg

http://www.kenable.co.uk/product_info.php?products_id=2514

[Reid Malenfant]

I have to say, & it does make me wonder, why are all these things to test the mains available unless it was possible to get it wrong ;)

Cheers Martin :)

[Stratmangler]

http://instrotech.com/martindale-classic-check-plug-socket-tester-p-277.html

http://instrotech.com/images/Martindale/MARCP.jpg

[dave2010]

http://www.amazon.co.uk/s/ref=nb_sb_ss_c_1_11?url=search-alias%3Ddiy&field-keywords=socket+tester&sprefix=Socket+test%2Caps%2C455

The one from Kenable already mentioned (msg 11) looks about as cheap and good as any, unless you really want to test for 1001 fault conditions, or you want audible confirmations.

[sq225917]

I bet you've got the fuse in back to front....

[anthonyTD]

I bet you've got the fuse in back to front....

That will be it!:eyebrows::eek::lol:
A...

[Audioman]

These new regs piss me off. As far as I've been told they prevent DIY wiring except fitting a new surface switch/plug to existing installation. I am wondering if you will need a certificate to sell a house now? Frankly I am probably more capable of rewiring than some people who cliam to be professionals. Also in relation to kitchens fitted 'professionaly' they used fitters proporting to be muti-skilled to fit err bodge your wiring and plumbing.

So might be well to get it all tested anyhow. In theory you have to pay someone oodles of cash to fit a new security light frankly a rule I have ignored. Oh well better sign up for that electricians course before I attempt any DIY like plugging in the hi-fi :)

[Reid Malenfant]

Well I tested the socket, then I tested another, then I tested the upstairs ring on a couple of other sockets...

I'm buggered if I know what the hell the earths in these cables are connected to as it sure as hell isn't earth :eek:

I'm going to have to dig a bit deeper & have a good look at the whole installation to see exactly how the thing is wired up earth wise.

I reckon the system must be TN-S (wiki link to a diagram (http://en.wikipedia.org/wiki/File:TN-S-earthing.svg)) & the earth has gone bad, though that's a guess.

A quote from this wiki artical (http://en.wikipedia.org/wiki/Earthing_system)


It is possible to have both TN-S and TN-C-S supplies from the same transformer. For example, the sheaths on some underground cables corrode and stop providing good earth connections, and so homes where "bad earths" are found get converted to TN-C-S.

Which might well be what has happened..


I'll find out at any rate. I don't like measuring about 70V AC from Neutral to Earth, or about 90V AC from Live to Earth :rolleyes:

I still have 240V AC from Live to Neutral though thankfully :eyebrows:


Bugger, this might get expensive :doh:

[MartinT]

Good find, though, Mark. This may well have been what took the P600 out and you need to get to the bottom of it.

[stupinder]

http://instrotech.com/martindale-classic-check-plug-socket-tester-p-277.html

http://instrotech.com/images/Martindale/MARCP.jpg
That looks like a good idea for us.
I know the electrics in our place a "special" and we really ought to save up and have the whole place rewired.
Pretty sure that the main house doesn't have earth but what was the catering kitchen does. In the house there are 3 seperate boards (is that what they are called?) - one for upstairs, one for downstairs and one for the commercial kitchen. All the out door buildings are on the main board that comes into an old and leaky building (it's been like that for years) and we've had to build a room within a room to protect it.
Sometimes the whole thing worries/scares me:rolleyes:

[Reid Malenfant]

Good find, though, Mark. This may well have been what took the P600 out and you need to get to the bottom of it.
Possible though I doubt it :) I think it's more likely that it expired due to use, all that heating up to a fairly high temperature & cooling again isn't a recipe for happy power transistors :eyebrows:

We'll see though, I'm off to rip the kitchen to bits to get to the bottom of this problem :uhho:

[synsei]

It might get expensive Mark but it's a necessary evil bud. When you mentioned this yesterday I was thinking along the same lines as Martin. It's a shitty situation to be lumbered with... :(

[Reid Malenfant]

Well I think I have a handle on the problem :) Some monkey wired the house up :mental:

I'm not 100% sure as of yet as I need to get into the fusebox to see the wiring, I don't know why I never noticed this before if truth be known :doh:

There is a wire composed of about 7 strands that must be about 4mm^2 which has no insulation what so ever exiting the fusebox, this runs down somewhere out of sight to below where the main SWA cable is visible (nicely insulated up take note :rolleyes:). I'm assuming this is running to some form of earthing stake, though I could be wrong. I mean it might just be buried in the concrete floor for all I know :bog:

From what I gather it should actually be clamped to the steel armour of the dirty great big SWA cable that feeds the house :eyebrows: But of course it isn't :steam:

To find out what's going on in the fusebox I'll have to shut the whole house down for a while, I'll do that tomorrow morning...


Oh what fun :no:

[synsei]

Well, at least it has turned out to be something fairly simple, you can put your wallet away now... :lol:

[MartinT]

Yep - a good clamp to the armour should do it, but make sure that it really leads to earth and use a proper clamp with a safety tag so that it passes future inspection.

As a side benefit, you will find that the system sounds better with a good earth :)

[Reid Malenfant]

Not so I don't think, I can't just go connecting to the armour of the SWA cable - well certainly not that I know of anyway.

As I say, I'll take a look at the wiring in the fusebox to determine what that wire is supposedly meant to be doing.

I have a feeling that I'll need to get an electrician to connect a 16 or 25mm^2 earth cable to the fusebox & then to either the SWA armour or a dirty great big earth stake.

Either way I reckon the wallet is going to take a hit. Better than me taking one with a crappy earthing system :lol:

[Reid Malenfant]

As a side benefit, you will find that the system sounds better with a good earth :)
Yes & I don't even need to imagine that benefit! Knowing what I know it's immediately obvious :)

[MartinT]

Not so I don't think, I can't just go connecting to the armour of the SWA cable - well certainly not that I know of anyway.

As I say, I'll take a look at the wiring in the fusebox to determine what that wire is supposedly meant to be doing.

Oh yes, of course. I thought you had already established that. Be safe and use an electrician :)

[anthonyTD]

hi Mark,
if you have the newer type armoured cable coming in, your earth should be connected to the outer screen somewhere, i have this type now, but i still have the earth rod connected to the consumer unit too.
Hope you get to the bottom of it soon, be safe.:)
Anthony,TD...

[Reid Malenfant]

Cheers Anthony, I'm sure it'll all be sorted out very quickly indeed :D


Just think of the improvement I'll get in rejection of RF & other shite on the hifi :lol:

[Mark Grant]

When you get the earth working as it should your screened power cables might have more effect, not much point in screening if it's not connected to earth :)

It might be like an upgrade just by connecting the earth.:)

[Mark Grant]

http://instrotech.com/martindale-classic-check-plug-socket-tester-p-277.html

http://instrotech.com/images/Martindale/MARCP.jpg

They are good and every electrician has one but they don't show all faults especially Neutral and Earth are reversed.

have a look here near the bottom of the page.
http://martindale-electric.co.uk/martindale-classic-check-plug-240v-socket-tester-p-277.html


Note: Like all other standard socket testers, the Martindale CP501 will not detect common earth and neutral or earth neutral reversal

One of the more advanced testers that gives a guide to earth resistance would be good although they costs a bit.

http://martindale-electric.co.uk/martindale-ez150-socket-tester-with-earth-loop-measurement-p-285.html

http://martindale-electric.co.uk/images/Martindale/MAREZ150.jpg

[Reid Malenfant]

It might be like an upgrade just by connecting the earth.:)
Yes, I'm expecting things to be a bit different :)


Give it a few days & I should know the results, in which case I'll report back :cool:

PS, postal service is bag o'shite of late, no sign of those cables yet unfortunately... I had a delivery this morning that was posted on Tuesday :rolleyes:

[Barry]

They are good and every electrician has one but they don't show all faults especially Neutral and Earth are reversed.

have a look here near the bottom of the page.
http://martindale-electric.co.uk/martindale-classic-check-plug-240v-socket-tester-p-277.html



One of the more advanced testers that gives a guide to earth resistance would be good although they costs a bit.

http://martindale-electric.co.uk/martindale-ez150-socket-tester-with-earth-loop-measurement-p-285.html

http://martindale-electric.co.uk/images/Martindale/MAREZ150.jpg

Just use a multimeter!

[Reid Malenfant]

Just use a multimeter!
Well yes as that is exactly what I did as I own a few :)

Not everyone does though, so I can see the relevance of posting links to these things so others that don't & also don't know how to use one could test their own system just by plugging those testers into a socket :)

If I hadn't noticed a few things I would have been none the wiser about effectively not having an earth :eek: It only piqued my interest because I instantly had a feeling things needed looking into.

I really consider myself quite lucky actually that I did notice :eyebrows:

[Barry]

Well yes as that is exactly what I did as I own a few :)

Not everyone does though, so I can see the relevance of posting links to these things so others that don't & also don't know how to use one could test their own system just by plugging those testers into a socket :)

If I hadn't noticed a few things I would have been none the wiser about effectively not having an earth :eek: It only piqued my interest because I instantly had a feeling things needed looking into.

I really consider myself quite lucky actually that I did notice :eyebrows:

Agreed - but if you haven't done the wiring yourself and have checked that the connections are correct, then I suppose arming yourself with one of the connection/earth testers is not going to help much, as you will not know what to do if the tester reports a fault situation.

Not that a multimeter will tell you everything.

It will tell you of:


The phase/neutral polarity
The phase-neutral voltage
The phase-neutral DC offset
The neutral-earth potential difference
The neutral-earth loop resistance


It will not tell you the mains source impedance (unless you know exactly what you are doing!)

As has been pointed out elsewhere - treat the mains supply with the utmost of respect. Power stations can supply Gigawatts of power, and by the time it reaches your dwelling, there is at least half a Megawatt of power that can be pushed through your body if you are careless!

Regards

[Reid Malenfant]

Agreed - but if you haven't done the wiring yourself and have checked that the connections are correct, then I suppose arming yourself with one of the connection/earth testers is not going to help much, as you will not know what to do if the tester reports a fault situation.
I don't know too many people that would have a clue how to spot something wrong with their mains AC supply.

I also don't know how many people check or get their mains supply checked regularly? :scratch:

I can't think of anyone & indeed I didn't until I saw something odd that maybe only I would recognise or someone else that knows enough.


I guess I'd expect anyone to call a competant electrician if they find a fault, but at least they can check for themselves a whole lot of things which cover a whole aspect of being safe :)

[f1eng]

How often should your house be rewired?

Just had a new consumer unit cos I had an electric shower fitted but not sure of the vintage of the wiring (no bakelite light switches so that's a result)

The electricity board suggested every 25 years, probably very conservative. My house was re-wired 31 years ago when we bought it to replace round pin sockets. We are going to rewire this year or next to have more sockets and CAT6 throughout.

When I rewired a cottage in Wiltshire years ago some of the cable was still cotton insulated conductors in a lead earthing sheath...