Double switch wiring help needed (Hallway and NEW PIR light)

[rick85]

Hi all,

When we moved in I had an electrician make provision for an outdoor light to be installed in the future. This was done by changing the existing hall light single switch to a 2 gang.

I finally got round to installing the light outside and connecting to the new switch however I am unsure of the circuit and hope someone could please advise. I intend to connect firstly from the switch into a stand alone PIR which then connects to 240V/12V transformer controlling 3no. halogen lights.

It seems the spark has installed a 3core + earth cable between the switch and the hall ceiling rose. He has also ran the same type of cable (3 core plus earth) to the outside location for the new light. However none of the wires in this cable have yet been connected to the switch. (SEE PHOTO)

Untitled

• rick85
• 3 Jan 2011
• 1

I have shown how I think the circuit might be completed, however I am unsure??

- I cant understand where the live is taken from for the new outdoor PIR?

- Should the brown wire (the one that is not connected in photo) be left redundant (i.e. in terminal block)?

Should the two neutral (grey) wires be connected together in terminal block?

and finally is the disconnected black wire to be used as the switched live for the new PIR

Any help/advice would be appreciated.

Thank you

Rick85

 

[flameport]

Both grey wires connect together in the terminal block.

Black and Brown connect to the unused side of the switch, one wire in each terminal

You then need a short piece of wire to link the two switch terminals which have brown wires in them.

At the light:
Grey = neutral
Brown - permanent live
Black = switched live.

 

[rick85]

Thank you flameport.

Do you really need both a switched live and permanent live at the PIR?

I haven't got the PIR yet (will pick it up from shops tomorrow) however I assumed that it would only require a switched live feed and neutral return. ie. the PIR operates when the switch closes the circuit?

hope i make sense in what i'm saying?

Rick

 

[flameport]

Most sensors don't require a permanent and switched live, however as the 3 core cable is already there it may as well be wired in that way.
This leaves the option available for a different type of light/sensor which could be fitted in the future.