1. Visiting from the US? Why not try DIYnot.US instead? Click here to continue to DIYnot.US.
    Dismiss Notice

PIR's

Discussion in 'Electrics UK' started by chillout, 13 Nov 2009.

  1. chillout

    chillout

    Joined:
    10 Jul 2009
    Messages:
    609
    Thanks Received:
    1
    Country:
    United Kingdom
    Ive bought some lanterns, and am thinking of connecting up to a PIR. They range approx 10-15 metres. However my drive is only like 4 as I dont live in a mansion! Would it go off everytime someone walked past?

    Also are there any PIR systems that would work well for lighting at the side of the stairs?
     
  2. Sponsored Links
  3. Lectrician

    Lectrician

    Joined:
    18 Jul 2004
    Messages:
    8,470
    Thanks Received:
    399
    Location:
    Devon
    Country:
    United Kingdom
    Some PIR's have a sensitivity adjustment.

    Some PIR's come with plastic masks to mask certain areas.

    PIR's are far more sensitive to people walking aross the 'beam' than towards it.

    A PIR pointing downwards creates a small 'bubble' which is less sensitive and more localised.

    Personally, I am not keen on PIR's - they tend to operate frequently when they need not, no matter how hard you try to illiminate false triggering.

    All my rear lighting is switched, either inside or out.

    I currently have no front lighting at all, although I want to sort this ASAP as winter is HERE. I am still debating the notorious stress of seeing the lights outside ping on due to wind etc.

    I have, in the past, fitted lighting on drives connected to the electric gates. This then progressed to simply using IR beams (verys stable to false triggering, PITA to install in terms of running cables).

    We have fitted induction loops similar to those used on traffic light priority systems and traffic counters to some sites in the past, more so to trigger the opening of gates and doors for fork trucks and th like, but it does make me wonder weather this would be a good idea for the drive.

    Over engineered? Yup. I'm a spark.
     
  4. chillout

    chillout

    Joined:
    10 Jul 2009
    Messages:
    609
    Thanks Received:
    1
    Country:
    United Kingdom
    Like the sound of the IR beams. Can you recommend any at all?
     
  5. ebee

    ebee

    Joined:
    14 Aug 2005
    Messages:
    1,711
    Thanks Received:
    29
    Location:
    Lancashire
    Country:
    United Kingdom
    Passive infra red is the wrong technology for outside because of false trips.
    You wouldn`t use it for an alarm system.
    However for a lighting system it is often deemed accetable because a few false triggers for lighting is not usually a massive problem if kept to a minimum.
    Previously stated ways of reducing the range are good suggestions.
    Another one is to mount the detector higher up and tilted down.
    Of course this decreases detection sensitivity as well because (taken to extreme) its looking down at the top of your head with your body below it (small target) rather than a full body.
    So compromise is important.

    Active infra red is a transmitter in one pposition facing a receiver in another position. Break the beam an you get a detection. Of course the beam is narrow plus someone might step over it rather than thru it to avoid detection.
    Very false alarm resiliant though.
    Additionally twin or quad beams are often used and all beams must be broken simultaneously to trip thereby giving greater immunity from false trips by leaves falling etc.
    They are expensive though and usually work at Extra Low Voltage (12v, 24v, 50v) rather than Low Voltage (Mains) so you would need an interface such as a relay or contactor.
     
  6. chillout

    chillout

    Joined:
    10 Jul 2009
    Messages:
    609
    Thanks Received:
    1
    Country:
    United Kingdom
    Thats very interesting, sounds like a good idea, but not sure if I can justify the cost as sounds expensive. I may try a PIR and see how that goes, if not I'll look into this pending on the budget!
     
  7. RF Lighting

    RF Lighting

    Joined:
    31 Mar 2006
    Messages:
    19,989
    Thanks Received:
    1,352
    Location:
    Leeds
    Country:
    United Kingdom
    Have a look for clipsal infrascan PIRs.

    I have a couple of these at home. They are adjustable for range and sensitivity, so you should be able to fine tune them to suit your needs.

    Mine seem pretty immune to false activation.
     
  8. DIYnot Local

    DIYnot Local

    Joined:
    3 Sep 2019
    Country:
    United Kingdom

    If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

    Select the supplier or trade you require, enter your location to begin your search.


    Are you a trade or supplier? You can create your listing free at DIYnot Local

     
  9. Sponsored Links
Loading...

Share This Page