Problem of the week

[Maplasterelec]

Ok. There should only be 2 3c+e at 1 of the smokes the other could be taken as the feed for the loft light? But as the smokes aren't working correctly but are interlinked, are the using the cpc as a line?

Matt

 

[steptoe]

Cpc used correctly, but the colours are used differently at each smoke.

 

[Maplasterelec]

I assume the live stays the same but it's the neutral and the interlink that swaps over?

 

[Evans Electric]

So one of the lighting 3 core/E has been hooked up into the smokey circuit and visa-versa. ??

I knew it was those Smokies all along!!

Sounds like a right crock up, TBH .

 

[tonyyoung]

Hi,

Whenever i get faults like this my approach maybe unusual but i tend to test the voltage at the fittings and get a good look at how its been wired. ( everyone is different ! ) Then i would disconnect cables and check which one is the feed and which ones are switches. Then it is just a case of making sure correct voltages are present and connect it back up. If it is not that straight forward and things are peculiar because of a loose connection somewhere then i would open up ceiling roses and work my way back to the source.

Tony

 

[markyboy2782]

Hi

I'd be interested in this, currently in training so any extra real life scenario questions would be a big bonus in my eyes.

Thanks

 

[gavindrummond]

So when are we having another problem to work out ?????

 

[sprocketflup]

more importantly, has it been a week yet?

 

[Manator]

more importantly, has it been a week yet?

I think Sunday is the last day, so if anyone has any more ideas please jump in with them.

 

[steptoe]

sorry guys, just in from work,

Im at work tomoz for a while too, then I'll reveal the answer,

I'll post up more hints in a bit,

for now the scenario is that somehow Mr DIY has decided to alter the wiring to the smoke detectors to get his loft light to work, the smoke detectors are connected to both landing light AND hall light.!

 

[Evans Electric]

Watson !!!! Did I not suggest this in post 48 ?

" You did indeed Holmes , shall I hail a cab to take us to this Mr Steptoe's residence?"

" Yes, do that Watson, and bring your service revolver"

 

[springcrocus]

Has anybody asked themselves WHAT voltage is usually applied to the interlink wire in the smokies?

 

[Guy]

With the info we have I admit that I need some colour pencils . I have found this thread to be a good learning tool and am looking forward to Steps summary later. Hope 'problem of the week' continues.

 

[Maplasterelec]

What I would do as never seen this fault before is disconnect all switches lights and smokes, then bell them out to find out what cables go where and hope to find the dodgy feed to the loft light, or find a dodgy jb that feeds it.

Matt

 

[Manator]

With the info we have I admit that I need some colour pencils . I have found this thread to be a good learning tool and am looking forward to Steps summary later. Hope 'problem of the week' continues.

This is a very useful tool, when faced with a problem I also try to draw the circuits it helps to physically see on paper where things do not look right. Using different colours helps to identify each circuit and does not overfill the schematic drawing I have done.

 

[steptoe]

Ive just finished work, need to do some paperwork, then i'll do a summary of my findings, and what I done,

springcrocus, I have no idea, but I think they were fried by this stage anyway, and simply amounted to 2more JBs to investigate.

 

[springcrocus]

The interlink voltage is ELV, usually 9v and this MIGHT be enough to make a lamp glow dimly. Anyway, applying 240v to the interlink will certainly fry them, part of the reason why BS5839 forbids the use of the brown wire for the interlink (see quote below).

I thought that Apprentice87 was on the right track in post 56 when he recognised that only a single lamp glowed dimly. To me, this says high resistance or low voltage so the smokes seemed a likely place to take a gander.

"Clause 16.5 © of BS 5839-6: 2004 states, with regard to the wiring of Grade D and E systems, that

 

[steptoe]

the colour used to identify the phase conductor of a control circuit or extra-low voltage circuit must (excluding brown) be black, red, orange, yellow, violet, grey, white, pink or turquoise

every day is a school day, never knew that applied to smoke detectors,

scoobed my friend,

 

[Zeespark]

+1 for both from Me

AndyGuinness

 

[steptoe]

sorry guys that I havent got back with the solution for this,

everything has just snowballed on me and Im flat right now, literally got home after midnight tonight,

Ill deffo get it up on sunday, unless something mad happens, Im off this sunday,