General questions
What is infrared?
Infrared is a type of radiation with a wavelength that is longer than visible light. It cannot be seen, but it can be detected. We can sense it – as heat. Even objects that we think of as being very cold, such as an ice cube, emit infrared.
Do Irisys people counters emit infrared?
No, they merely detect naturally occurring infrared given off by people as heat.
Do Irisys people counters use passive or active infrared?
Irisys people counters detect naturally occurring infrared, and are therefore passive infrared technology.
What is the difference between passive and active infrared?
Active infrared is when infrared light is emitted and then detected when it bounces back off a surface. Passive infrared is the infrared given off naturally from the surface of a material.
So called ‘beam break’ counters use active infrared, Irisys people counters use passive infrared.
Technical product-specific questions
What is the widest door I can count through?
This depends on the height of the counter mounting. The maximum size of a counter's field of view is approximately 4.25m at maximum recommended height and 4.5m at maximum allowed mounting height. It is possible to connect up to 8 counters together in order to cover much wider entrances.
What is the highest I can mount the people counter?
Depending on the ceiling height, there are versions of the counter available which can be mounted up to a recommended and maximum height. For 20 degrees we recommend 14.5m and the maximum allowed is 15.5m. If it makes installation easier, you can always mount the counter lower down using a bracket off a wall rather than accessing a very high ceiling.
What is the lowest height I can mount the people counter?
The absolute lowest height that an Irisys people counter will operate is 2.2m. We recommend mounting the counter higher than 2.5m if possible.