lighting wiring

[Steve mcqueen]

Hi

Just about to break into existing lighting circuits x 3 all on 2 way switching in order to add 5 PIR's via a new contactor. Customer now wants to keep existing 2 way switching. Any thoughts please?

Steve

 

[Richard Burns]

Use a relay with CO contacts instead of the contactor or adapt a NO/NC contactor to operate as a 2 way switch?

Depends on the functionality you want.
Do you want the PIR to act as an overall control but once it is on the 2 way switching still operates.
Do you want the 2 way switching to act as a manual override of the PIR
Do you want the 2 way switching to act as a manual off for the lights if the PIR is on.

 

[Steve mcqueen]

Thanks for your reply. They just want to keep the switches in case the room is used for something else in the future. I would have blanked them off and linked them out but they Still want to be able to operate the lights via the switches.

 

[Richard Burns]

For a default of ON then wire the PIR to switch permanent line to the lamp, leave the switches as they are.
If the PIR turns the light on it will be on, the 2 way switching will not be able to turn them off (but would be able to leave them on if the PIR goes off :frown, if the PIR is off then the 2 way switches will work as they did before.

For a default of OFF wire the PIR to switch the switched line to the lamp, leave the switches as they are.
If the PIR is off then the lamp is off, if the PIR is on then the light switches can turn the lamp off.