The good people at Danlers have some great guides related to PIR occupancy switches, where to use them, what does all the technical jargon mean, and so on.
Today we were looking at the "PIR occupancy switch specifications" section and we found it inspiring. What is a PIR switch? What does it mean "adjustable time lag"? What's an adjustable photocell? These and some other questions are dealt with below.
What is a PIR detector?A PIR is a passive infra-red quad person detector. It is a sensor that measures via infra red the light radiating from objects or beings in its field of view / area of sight.
What is the Adjustable Time Lag?The PIR detectors have an adjustable time lag adjustable in nine steps, with the following approximate values: 10 sec, 20sec, 40sec, 1.25min, 2.5mins, 5mins, 10mins, 20mins, 40mins.
What is an Adjustable Photocell?A photocell is "inhibit on", which means that it will "inhibit the lights" from switching on when someone enters an area with plenty of ambient light.
Also, if the photocell detects that someone already is in an area and the lights are switched on, it will allow the lights to remain on (regardless of any increase in the light level).
This feature is for avoiding any nuisance like switching off the lights when people are still in the room or there's a meeting going on in that venue.
The photocell detects a range of 100-111lux (and photocell inactive) falling on the working plane.
What Load do Danlers PIR Switches Take?
What is the maximum load that the Danlers PIR switches can take? All the Danlers PIR occupancy detectors can switch up to 1500W 6Amp at 230V of resistive, transformer, or fluorescent loads, up to 500W 2Amp of low energy lighting loads (like the compact fluorescent and the LED lights), or up to 250W 1Amp of fans / metal halide lamps.
Of course, a few PIR switches can be wired in parallel in order to control the same load.
The Initial Start-up ModeWhen a PIR switch is set up and the mains supply is connected to the PIR occupancy switch for the first time, it goes through something called "Start-up mode".
The switch is turned on for 1min, then switches off and enters its "Operating Mode". Please note that if a manual wall switch is feeding the PIR occupancy switch, it will go through the start-up mode each time the wall switch is switched ON.
But if you wire the manual wall switch in the alternative position, the supply to the PIR occupancy switch will be uninterrupted and it will remain in "operating mode" (it won't go through "start-up mode" each time the wall switch is ON).
Do you have any questions concerning the Danlers Occupancy Switches and PIR detectors? Please leave a comment below, or contact Danlers via their website.
You can purchase Danlers occupancy detectors and time lag switches via the Lighting PIR section on our website.