N. V. Nederlandsche Apparatenfabriek NEDAP SENSITGW Manual Do Utilizador
SENSIT SYSTEM | MANUAL
Frequently Asked Questions
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Frequently Asked Questions
19 FREQUENTLY ASKED QUESTIONS
GENERAL
W
What types of SENSIT sensors are available and what is the difference?
There are 3 different types of SENSIT sensors available:
1
There are 3 different types of SENSIT sensors available:
1
SENSIT IR - Magnetic and optical sensor suitable to be built-into the floor of
each parking space.
2
SENSIT Flush Mount - Magnetic sensor suitable to be built-into the floor of
each parking space.
3
SENSIT Surface Mount - Magnetic and optical sensor for mounting onto the
floor of a parking space
What is the accuracy of the SENSIT Flush Mount?
The magnetic sensor can achieve an accuracy of 95%.
What is the accuracy of the SENSIT IR and SENSIT Surface Mount?
The combination of the magnetic and optical sensor has an average accuracy of
above 98%.
How scalable is the SENSIT system?
The SENSIT system is quite scalable. The theoretical maximum number of SENSIT
nodes in one network is about 65000. In general, large installation need to be
divided into smaller sub-networks (segments), which makes it better manageable
and easier to understand. Sites that have more than 500 sensors or more than 15
Relay Nodes need segmentation. Please contact your Nedap account manager.
What is the temperature range for the SENSIT and SENSIT
IR
?
The temperature range for both SENSIT as well SENSIT
IR
is -40°C to 85°C [-40 to
185°F]. Temperatures below -30°C [-22°F] might affect accuracy of the magnetic
sensor. The accuracy on the optical sensor remains unchanged.
How does the dual sensor technology principle work ?
The optical sensor is based on IR reflection, using a modulated high power IR LED
transmitter and a sensitive IR diode as receiver. The IR radiation is reflected by the
bottom of a vehicle and captured by the IR diode.
sensor. The accuracy on the optical sensor remains unchanged.
How does the dual sensor technology principle work ?
The optical sensor is based on IR reflection, using a modulated high power IR LED
transmitter and a sensitive IR diode as receiver. The IR radiation is reflected by the
bottom of a vehicle and captured by the IR diode.
The 3D magnetometer senses the variation in the earth magnetic field when a
vehicle stops above the sensor. The magnetic status of the SENSIT sensor switches
to “occupied” if at least one axis (X, Y or Z) measures a deviation of more than
50mGauss compared to the stored calibration vector.
The IR sensor is potentially more accurate but sensitive to dirt, snow and ice. The
triple axis magnetometer however is not influenced by dirt, snow or ice. By default,
the sensor checks its IR sensor and magnetometer status every second.
Both technologies work together to provide reliable and accurate vehicle detection.
There are different modes of operation impacting how the status is calculated.
vehicle stops above the sensor. The magnetic status of the SENSIT sensor switches
to “occupied” if at least one axis (X, Y or Z) measures a deviation of more than
50mGauss compared to the stored calibration vector.
The IR sensor is potentially more accurate but sensitive to dirt, snow and ice. The
triple axis magnetometer however is not influenced by dirt, snow or ice. By default,
the sensor checks its IR sensor and magnetometer status every second.
Both technologies work together to provide reliable and accurate vehicle detection.
There are different modes of operation impacting how the status is calculated.
For each individual sensor, the system tracks the actual status of the IR and magnetic
sensor. Based on this information, the “calculated state” of the sensor (i.e. “free” or
“occupied”) is determined.
How does the energy efficient Wireless SENSIT Network work?
The medium access protocol is based upon time division multiple access (TDMA).
Time is divided into time slots, which (Relay) nodes can use to transfer data without
having to content for the medium or having to deal with energy wasting collisions of
sensor. Based on this information, the “calculated state” of the sensor (i.e. “free” or
“occupied”) is determined.
How does the energy efficient Wireless SENSIT Network work?
The medium access protocol is based upon time division multiple access (TDMA).
Time is divided into time slots, which (Relay) nodes can use to transfer data without
having to content for the medium or having to deal with energy wasting collisions of