Outside lights with PIR and manual overide

bud · Sep 19, 2015

Hi , I am a newbie trainee and would like to understand something please. I am working with someone else, replacing outside pir lighting. The property has 3 outside lights front, and 3 at the rear. They are currently the half lantern style PIR slave units. the front ones have a manual overide switch inside the property like a light switch. The owner is therefore able to switch the front lights on when wanted. At the rear, it is a little more complicated, the switch for manual override has never been satisfactory since it was installed 5 years ago. Also two of the rear lights will sometimes spontaneously come on and stay on for 48 hrs or so then go off again. The owner wants the lights replaced and hopes to update them to a stainless steel more modern looking light. The rear lights havent been touched yet. The front supply to each light has 2 live 1 neutral and 1 earth wire. The lights the owner supplied, although PIR are incompatable with this as having different internal fittings. We are having some difficulty obtaining any lights that have a manual overide and PIR. The ones bought were about £30 each. Can someone please explain the wiring to me ? and if they know where we could obtain suitable inexpensive lighting? Would separate PIR sensors with manual overide be any good in this case? The property needs the 3 lights because of the angle of cover. Forgive me for sounding so green!:smile5:. Thanks for your guidence in advance.

HappyHippyDad · Sep 20, 2015

I generally use the £10 PIR from screwfix. It has good reviews and I have fitted plenty without issue. This has 4 terminals in it for the earth, neutral, live in and live out. In otherwords you can wire it with 4 core flex so that one of the cores is used as a manual overide on a seperate switch. I would have thought all stand alone PIR's must have seperate terminals for the live in and live out so all could be wired to have a manual overide switch.

As for light fittings with in built PIR's, you would have to open up the fitting to check first to see if the live terminal going straight to the light from the sensor is accessible. If it isn't then that light could not be wired with a manual overide, however it may already have a manual overide function built into it (sometimes by switching on/off/on quickly), you would need to check the manufacturers instructions for this.

sampenfold · Sep 26, 2015

I 2 have fittings with built in PIR's at home, they are both switched on/off from one switch. The switch is usually left on, so therefore operating by the sensor. If I want to turn them on before I walk outside for example, I simply turn the switch off and then on again. The light will remain on for the set time on the fitting.

Every fitting with a PIR that I have ever installed has functioned this way.

Richard Burns · Sep 26, 2015

PIR lights come in a variety of wiring arrangements.
The sort of stainless steel lanterns that you are looking for tend to have very integrated wiring that do not permit an additional load to be connected or manual override to be wired in, but often have an electronic override function.
If you only have three terminals in the light fitting and no access to any other internal wiring then you would have to rely on the manual override function if this is part of the lights control system. Usually turn on and off quickly.

If you have access to the internal wiring then it is possible that you may be able to splice into the feed to the lamp itself to give a manual override. However be aware that some sensors do not like a live load on the output and can fail, also if you do do this then you have probably invalidated any guarantee.

If the lights have the capacity to take an additional light fitting and have four terminals then this is easy and manual override can be installed directly to the fourth terminal.
Using a separate PIR sensor is probably the easiest method (though the lights should not have their own sensor) and gives you maximum flexibility to add and remove lights and have manual override and linked operations.

This diagram shows the methods I have mentioned in reverse order to my description, with the separate sensor first at the top showing one common method of wiring using three core T&E cable (or four core flex) and the four terminal on the lower left, thee terminal with a splice into the wiring in the middle and the three terminal with no modifications on the right.

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