Terminating unused electric cable

[PBC_1966]

Reminds me of The Two Ronnies optician sketch: "Oh, I only need glasses for reading - And seeing."

 

[Milleniumaire]

Cut a big hole in the edge of the ceiling last night. Terminated the cable in a junction box and pushed it through the hole into the ceiling space above, then filled the hole in.

Job done and a little safer than the previous occupants leaving a live wire sticking out of the wall.

 

[Taylortwocities]

I hope that you remembered this...

all connectors must be accessible if they are the screw type.
You need to get a "Maintenance free" terminal block, and safely terminate the cables there.

 

[bernardgreen]

Since it is a dead end no current will be flowing through the contact areas between conductors. Thus provided the terminals keep Live, Neutral and Earth apart even if the screws loosen over time there is no real need to maintain the termination by checking the screws are tight

 

[ban-all-sheds]

http://images.google.com/images?q=heat+shrink+cap

 

[Milleniumaire]

I hope that you remembered this...all connectors must be accessible if they are the screw type.

Define accessible!

 

[JohnW2]

Define accessible!

It's not formally defined, but is largely down to common sense. In particular, 'within a wall' or 'under floorboards' is not usually regarded as 'accessible'. On the other hand, above a top floor ceiling and accessible via the roof space usually is regarded as 'accessible'.

Kind Regards, John

 

[Taylortwocities]

Unfortunately it is NOT accessible as a false wall has been built around a fire place directly above this point and so this would have to be removed. It is also the other side of the joist, so can't get at it through the floor boards above.

 

[Milleniumaire]

So, if 'under floorboards" is not usually regarded as 'accessible' why are "standard" junction boxes used to connect cables? When would you ever be able to use a "standard" junction box rather than a "maintenance free" terminal block?

In my house ALL cables are "within a wall" or "under floorboards". So does that mean none of them are accessible? I would be interested to know how many people have used these "maintenance free" terminal blocks. Let's face it, they are expensive for what they are:

this

or

this

 

[ban-all-sheds]

So, if 'under floorboards" is not usually regarded as 'accessible' why are "standard" junction boxes used to connect cables?

They are not, any more. Or at least, they should not be.

When would you ever be able to use a "standard" junction box rather than a "maintenance free" terminal block?

When it's accessible.

Or when you have a time machine. Regulations change - what was OK in the past is not OK now.

In my house ALL cables are "within a wall" or "under floorboards". So does that mean none of them are accessible?

Probably.

I would be interested to know how many people have used these "maintenance free" terminal blocks.

All those who have wanted to comply with the Wiring Regulations since 2008.

Let's face it, they are expensive for what they are:

There's no exemption from the regulations because MF JBs are more expensive than non-MF.

 

[JohnW2]

So, if 'under floorboards" is not usually regarded as 'accessible' why are "standard" junction boxes used to connect cables?

Mainly because they were installed prior to the regulations requiring them to be accessible. In some cases of more recent installation because people have ignored (or been unaware of) the current regulations.

When would you ever be able to use a "standard" junction box rather than a "maintenance free" terminal block?

In the past, anywhere. For new JBs, only if they are 'accessible' - as I've said, in an accessible roof space is probably one of the most common situations - or if a JB can been accessed through the hole after removal of a removable downlight.

In my house ALL cables are "within a wall" or "under floorboards". So does that mean none of them are accessible?

Probably - but they were very probably installed at a time when there was no requirement for accessibility, so they are still 'OK'.

I would be interested to know how many people have used these "maintenance free" terminal blocks.

No electrician should have installed any inaccessible JB which was not "maintenance-free" since the regulations changed. Many non-electricians probably are not even aware of the current regulation, so may well be failing to comply with it.

Kind Regards, John

 

[Milleniumaire]

..... in an accessible roof space is probably one of the most common situations - or if a JB can been accessed through the hole after removal of a removable downlight

I was wondering about that, as the electrician that changed all my 12V downlights to 240V used standard junction boxes to replace the transformers and that was only about 4 years ago. But I guess these are accessible through the hole by removing the downlight fitting.

 

[EFLImpudence]

I was wondering about that, as the electrician that changed all my 12V downlights to 240V used standard junction boxes to replace the transformers and that was only about 4 years ago. But I guess these are accessible through the hole by removing the downlight fitting.

They should also not be used there because they have no cable restraint.

 

[JohnW2]

I was wondering about that, as the electrician that changed all my 12V downlights to 240V used standard junction boxes to replace the transformers and that was only about 4 years ago. But I guess these are accessible through the hole by removing the downlight fitting.

They should also not be used there because they have no cable restraint.

Indeed, that is true of 'standard' JBs. However, as you are aware, there are non-'MF' JBs made for that purpose which do have cable restraint. The requirement for restraint has, of course, existed for a lot longer than the requirement for inaccessible JBs to be 'MF'.

Kind Regards, John

 

[Milleniumaire]

The house I'm doing up uses standard junction boxes to connect the ring main to each transformer. Is this okay, because it is the transformer that is wired to the light fitting, or should the JB's have cable restraint? These downlights are in the bedrooms and bathroom and so are accessible through the loft, but I've noticed the loft insulation is simply pulled away from each light. Given they are all fitted with 50W halogens the heat generated does concern me. As a result I was thinking of getting these 12v downlights replaced with 240v LED fittings and had assumed it would be a relatively easy job for an electrician as they could simply remove the transformers and wire each light fitting into the junction box. However, if the junction boxes need to be changed to types that have cable restraints then this is obviously a bigger job.