iScout® System User’s Manual
23
© McQ Inc 2008
4 iScout® Deployment Guidance
The iScout® sensor can be deployed in a variety of settings depending on the monitoring
scenario. Some deployment options include:
1.
Direct burial in the ground.
2.
Setting the unit on the ground.
3.
Placing the sensor on a stake that is in the ground.
4.
Locating the unit in a building or a structure.
The iScout sensor can be deployed using the four settings above, but certain modes will not work
in certain positions. It is recommended that when using the seismic sensor, the unit be buried
using a cable antenna or the stalk antenna sticking out of the ground. If the sensor is not buried, it
is highly likely that false alarms will occur frequently. When using the PIR sensor, it is
recommended that the sensor be positioned off the ground on a provided stake or on surrounding
objects. Attempt to remove all objects that could move in front of the beam and trigger the PIR
transducer. The acoustic transducer should be used above ground as well and in the same
direction as projected blasts. When the unit is buried, the provided lens cover should be used to
cover the PIR window to prevent scratches and the rubber stopper should be placed in the
acoustic hole to prevent dirt from clogging it. The magnetic transducer in the sensor can be used
above ground or buried. The transducer in the unit can function without having to be raised.
4.1
Using the PIR Sensor
The PIR sensor is a pencil beam that detects a change in the temperature against a relatively
stable background thermal level. Sudden changes caused by a target against the stable
background cause a detection to be reported.
Ideally, the sensor should be set to stare at an unchanging background to optimize its detection
performance. Examples of stable backgrounds include the inside of a building looking across the
room at a wall, outside looking at a dense forest slightly below the foliage concentration
(minimizing effects of blowing limbs or leaves), in a valley looking at the wall of a hill or
mountain, etc.
Placing the sensor on the ground to do a PIR detection increases the possibility of picking up
nuisance alarms due to ground cover that may be in the near vicinity of the PIR lens and subject
to movement due to wind. If the sensor is to be deployed on the surface, then the unit should be
stabilized to prevent it from moving due to wind, and any nearby vegetation that may be directly
in the view of the PIR lens should be removed. Placing a sensor on a stake that has already been
driven into the ground helps reduce nuisance alarms that may be generated due to wind effects.
It is now important to ensure that the sensor base is securely attached to the stake to prevent it
from rocking about the inset screw. Additionally, it is important that the stake be firmly driven
into the ground and secured prior to attaching the sensor to it.
CAUTION: The sensor should never be attached to the stake prior to the stake being
pushed or driven into the ground. Significant case damage can occur if the sensor is used
to “push” the stake down into the ground.