Main powered smoke alarm - 25mm junction box

[benjiman]

ive just got some mains powered smokes from screwfix. In the instruction they say they should be mounted to any standard juction box with a minimum depth of 25mm.

Im not sure what they mean by this. Anyone help?

Do they mean a terminal/connector block? Or is there some kinda of special junction box that i have to buy?

 

[Qedelec]

Cut a hole to accomodate a circular dryline box in the ceiling and attach the sensor plate to that, it has 50mm centres.
The box also satisfies the regs concerning enclosing all connections.

 

[benjiman]

Cheers mate, where do i get a dryline box? Does screwfix sell them?

I guess doing the connections into a terminal block and shoving the connections back into the hole is a big NO NO?

 

[Qedelec]

Yes screwfix do stock them and using connector block wrapped up with tape is not acceptable, all connections must be enclosed, Chocbox is doing a roaring trade.

 

[slippyr4]

round dry lining box

 

[benjiman]

Thanks alot guys, will get a few of those.

So the connector block and conections go into the dry line box then yeh?

http://www.screwfix.com/app/sfd/cat/pro.jsp?cId=100096&ts=41662&id=12442

This one doesnt have the dimentions. But i guess the screw on the baseplate will most likely line up right?

Edit just found out the difference between chocbloc and connectro block. I thought they were the same!

So will enclose in chocbloc,

 

[benjiman]

Ok i just realised that both a chocbox and a circular drylining box are not going to work for my smokes.

what if i enclose the connections in a chocbox and then shove this back into the hole. Then attach base plate of smokey to the ceiling with the wall plugs provided.

Does this comply with regs? All connections will be securerd. But i cant see how i can use a drylining box. Unless im not picking up on the idea?

 

[slippyr4]

The drylining box counts as the enclosure. So you can use either:

- drylining box + chocolate block

- chocbox + chocolate block


Mine were done the first way. the base plate of the smoke alarm fits over the top of the drylining box. It is not fixed to the drylining box- the screws are into the plasterboard surrounding the drylining box.

 

[benjiman]

Oh i see!! thanks alot mate, much appreciated.