Mounting the PIR Lens
The PIR lens should be mounted to the case you have your board
mounted in. The lens should be centered over the PIR Sensor and be
0.65" from the top. Make sure you mount the lens with the
"ridges" faces towards the PIR sensor. Do not scratch the
lens on either side. Also, do not mount any glass over top of the
PIR lens. Glass will not let infrared heat to pass through to
trigger your PIR sensor. To mount the lens to your case drill a
1" hole centered about the PIR sensor. Glue the PIR lens to the
inside of the case (lens ridges pointed in, smooth side out), and
glue the lens to the case with Marine GOOP (can be purchased at your
local hardware store). Note: we do not recommend using double
sided carpet tape to secure your PIR lens.
PIR Motion Sensors Basic
Overview for Effective Use
All PixController motion control
boards use a PIR motion detection sensor. PIR
stands for Passive InfraRed, which detects warm
targets in motion over ambient background temperature. A stationary
target, or a target not moving can not be detected. The target must
also have a warmer surface temperature than the ambient background
temperature in order to be detected.
The size of the target and the distance of the target from the PIR
sensor will also effect if the target can be detected or not.
Smaller targets such as birds and small mammals may not be detected
especially if they are moving fast or are at a great distance from
the PIR sensor. Larger targets such as medium size and large size
mammals are easily detected within the range of the PIR detection
area (see below). However, if you increase the the sensitivity of
the PIR sensitivity POT you can detect
smaller targets, but you run the risk of a greater chance of false
Sensor Detection Area
As ambient background temperatures rise to near 96ºF, the
difference between the target and ambient background temperature
decreases for warm-blooded targests. The sensitivity of the PIR
sensor declines in this instance. However, as ambient
background temperature decrease the opposite is true and the sensor
PIR becomes more sensitive. Under these
conditions you can adjust the PIR sensitivity
POT to accommodate your detection range needs. The graphics
below show an example of the PIR detection area at around 69ºF.
The PixController PIR sensor is unique in that the target does not
need to be moving from right to left, or left to right. Our sensor
can detect the target in any vector of travel (say up and
down target movement), which is very important if you plan to mount
your sensor in an elevated position for say security reasons. Other
competitive PIR detection electronics will fail in this case.
The red area is the PIR detection area in the above graphic.
Fast Re-Trigger PIR detection electronics
The PixController PIR
detection electronics is unique in that is a very fast recovery after
each PIR detection trigger. Competitive PIR electronics will not be
able to detect the next detection trigger between 5- 20 seconds.
This makes items such as Walk-Test mode
on their system an unusable feature. The the key is that the
PixController PIR circuit used advanced digital detection
electronics, where our competitors use older analog PIR detection electronics.
Our PIR detection electronics recovery time is only 1/2 second! This
is why you will see unique features like continuous recording as
long as the target is present in the PIR detection area for our
video systems. This feature alone is an invaluable tool for building
Universal Board Mounting - PIR Sensor Considerations
Our new PIR sensor
will allow the board to be mounted horizontally or vertically
without needing the PIR sensor to be rotated like you see in other
Our PIR sensor circuit is the most rugged and reliable on the market
today. Triggering occurs when a change in infrared levels is
detected, as when a warm object moves in or out of view of one of
the sensor's "eyes." Our PIR sensor design is quite
resistant to false triggering.
With other boards you need to consider how you mount your board,
either vertically or horizontally. Since our board is unique you can
mount it horizontally, vertically, or upside down without the need to remove the
PIR sensor and rotate it, which can destroy your sensor if you attempt
this by yourself. This is why we chose a special PIR sensor to alleviate
this issue, and a main reason why we consider quality and our
customers first. Also, our sensor can can be mounted in elevated
positions such as from high in a tree. Since our competitors PIR
sensors need the target moving from left to right or right to left
this elevated position will not work.
- Point the sensor away from the rising or
setting sun. In general, North or South works well, but your
local site conditions could dictate otherwise
- Keep the sensor aimed at an area that will not
have intense, direct sunlight warming all or part of the
detection area. Shadows of trees or clouds moving across a
sun-warmed area can cause a momentary temperature drop which
could cause a false event to be recorded. The warmed air rising
from the ground can cause problems too.
- Do not place the sensor
in a location where direct, bright sunlight will fall on the
- Tall, sun-warmed grasses or other vegetation
blowing in a breeze can be detected. Point the sensor away from
dense, sun-warmed vegetation which can trap heat.
- Even in a shaded area, keep the sensor pointed
away from dense shrubs or trees that can retain the days warmth.
A warm evergreen or other dense shrub will hold the days heat.
If the air temperature drops at night - and the still warm shrub
moves in the wind, this movement could be detected.
- If the area is known to have many small birds /
mammals, you will surely get many empty pictures, as these
active, fast animals will often leave the frame before a picture
can be taken. Orient your sensor to your
- Wind (moving air) can
cause false events. The moving air might be warmer or cooler
than the background. Place the sensor in an area sheltered from
strong winds when you use your PIR sensor equipped cameras in a
location prone to high winds.
- Wind can also cause
movement of the tree or other object you have your sensor
mounted to. Make sure to secure your sensor to an object that
will not sway in strong winds. Trees should be a minimum of
10" in diameter.
- Make sure your equipment
is fastened securely. Movement of the equipment can be interpreted
as motion by the sensor.