Extending light switch cable, 5A or 20A Junction Box?

[ncollins]

I'm replacing the ceiling pullcord light switch in a bathroom with a wall switch outside the bathroom door. The re routed cable doesn't reach so am planning to extend it by using a 5A junction box( small size fits to partition batten). I read somewhere that 20A junction boxes should be used in lighting circuits, is this correct even if it's just a single 10mm switch cable?

Nic

 

[Chri5]

10 mm switch cable , maybe you mean 1.0mm.

Junction boxes can't be hidden away since they could require servicing in the future.

If you check the fuse for the lighting circuit at the board it is likely to be a 6 amp.

http://www.tlc-direct.co.uk/Main_Index/Cable_Accessories_Index/Junction_Boxes/index.html

Your choice, from the link.

 

[Chri5]

10 mm switch cable , maybe you mean 1.0mm.

Junction boxes can't be hidden away since they could require servicing in the future.

If you check the fuse for the lighting circuit at the board it is likely to be a 6 amp.

http://www.tlc-direct.co.uk/Main_Index/Cable_Accessories_Index/Junction_Boxes/index.html

Your choice, from the link.

 

[ncollins]

Yes I did mean 1.0mm! The lighting circuit is on a 10A switch at the CU. I hear what you say about access to junction boxes, I'm just trying to find the neatest most expeditious way of extending the cable to reach the switch. I had considered just using choc box connectors? Unfortunately there's another floor above the bathroom so getting at the junction boxes from above would involve major hassle

 

[riveralt]

Yes I did mean 1.0mm! The lighting circuit is on a 10A switch at the CU. I hear what you say about access to junction boxes, I'm just trying to find the neatest most expeditious way of extending the cable to reach the switch. I had considered just using choc box connectors? Unfortunately there's another floor above the bathroom so getting at the junction boxes from above would involve major hassle

The best option is to extend the cables by crimping, no access issues - but use a proper ratchet crimper rather than the bog standard ones.

 

[ncollins]

Thanks, that looks like the best way to go although I've just been looking at 'maintenance free' junction boxes which look like a viable alternative.

 

[riveralt]

Thanks, that looks like the best way to go although I've just been looking at 'maintenance free' junction boxes which look like a viable alternative.

Yes they are but they are much bigger than a 5 amp jb.
http://www.tlc-direct.co.uk/Products/ASJ804.html?source=froogle
For example is 140mm long 65mm wide
These work on a spring clip that hold the conductor in place once inserted.
Pain in the butt to get out though

 

[ncollins]

Yes that is quite large, Wagobox do a smaller one though and it would save me having to buy a decent crimping tool

 

[riveralt]

Yes that is quite large, Wagobox do a smaller one though and it would save me having to buy a decent crimping tool

The wago pushwire terminal block is smaller but the critical point is that while it holds the conductor it does not support the cable.
Consequently you will need to wrap it in a wago enclosure (JB) and they tend to be around 100mm by 50mm themselves.

 

[ncollins]

Yes, their single box is 108x44x39 so will fit nicely on one of the wooden battens.

 

[ban-all-sheds]

Wago do not claim compliance with BS 5733, nor do their products carry the required Maintenance Free symbol, therefore they do not comply with the Wiring Regulations for use in inaccessible locations.