Metal Cable tray -

[Loosefix]

Hi,

Wondering what method is best to go from a raised (metal) cable try into a wall chasing?  Do you you run the cable through one of the circular holes and use a grommet?  Or do you just cut the cable tray 'ridge' to exit the cable - this means running cable over jagged cut metal - which seems a bit of a rough way to do it - or am i being to fussy on this?

Advice appreciated...   Have a large cable tray running to a (90 degree) smaller one, that then runs behind kitchen units at low level and will feed various points:  Kitchen sockets, appliance circuit, and cooker!

While i'm asking questions ...   for kitchen sockets and/or appliance sockets always better to use 4mm radial?  

Thanks all, stay healthy! 

 

[Evans Electric]

I presume this is a commercial kitchen .... with cable tray .      What sort of cables are you running ?  

While i'm asking questions ...   for kitchen sockets and/or appliance sockets always better to use 4mm radial?  

Again , if this a commercial kitchen  , you design it accordingly .   If its  the usual domestic kitchen  a dedicated 2.5 ring  usually suffices  with a separate cooker circuit . 

 

[Loosefix]

I presume this is a commercial kitchen .... with cable tray .      What sort of cables are you running ?  

Again , if this a commercial kitchen  , you design it accordingly .   If its  the usual domestic kitchen  a dedicated 2.5 ring  usually suffices  with a separate cooker circuit . 

Its Domestic.  Funny how some sparks swear by 4mm and others perfectly happy with a ring. 

So yeah, cable tray just for convenience - just so happens that the main 'riser' cable tray thats carries Mains and Low voltage for the whole house drops into the kitchen so want to continue with a smaller horizontal one, and tap out with the vertical runs into the wall...   just want to use best method of going from tray into the wall.

 

[Evans Electric]

I never saw metal cable tray used in a house before .      If its twin /E   you'd need to put two cuts in the raised edge of the tray & bend it back , file the saw cuts .  

 

[Murdoch]

Why are you thinking you should use this method?

 

[Doc Hudson]

Its Domestic.  Funny how some sparks swear by 4mm and others perfectly happy with a ring. 

If using 4.0mm, the back-box depth and type of accessories becomes a key issue. Connecting a pair of 4.0mm conductors into some of these modern socket outlet terminals can be a right pain in the rear. And if it is a standard 25mm back-box and the customer has some slim-profile, hidden fixing-screw decorative sockets, the space behind the socket gets even more crowded. The last thing you need is 4.0mm conductors to tuck-away when trying to secure the nice polished chrome, flush plate, socket to the wall.

Doc H. 

 

[Loosefix]

Very Good point Doc! 

The tray is used as the house has a lot of centralised lighting circuits, plus with a divider the tray carries lots of CAT6, spker cables etc.  The reason i thought i'd carry it on is there is a 100mm space behind the kitchen units and its a way of cable managing 5-or 6 T&E's 

Bend it back ... why didn't i think of that! Cheers EE

 

[poni]

you should use a brass bush and lock nut or grommet strip when leaving cable tray.

 

[roys]

In days long gone by we used to use lead on the cut edge to make it a safe edge, not that I think this would be a good idea in a kitchen.

 

[Phoenix]

In days long gone by we used to use lead on the cut edge to make it a safe edge, not that I think this would be a good idea in a kitchen.

Some hot water 'tea' boilers for kitchens were made using a mercury tilt switch on the arm of the float valve to cut the element off when the level dropped too low. I think thats a worse idea than the lead on the edge of teh cable tray

 

[roys]

Some hot water 'tea' boilers for kitchens were made using a mercury tilt switch on the arm of the float valve to cut the element off when the level dropped too low. I think thats a worse idea than the lead on the edge of teh cable tray

Yip that doesn’t sound like the best idea in the world

 

[Evans Electric]

Fine as long as the glass tube is't broken I guess .   

Mercury switches  used in medical theatres  because of the switch arc igniting gasses .      How weird is that stuff ?   

 

[Tony S]

When I first started in this trade we had dozens of mercury switches on the plants. I can’t think of any glass tubes failing, the copper pigtails breaking off or being out of adjustment were the normal culprits.

And yes the canteen Jackson tea urn had mercury switches.