CP3 version 3003
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Example:
A multi-storey car park of five floors with 200 spaces on each floor.
If the system is 100% occupied, 1000 cars will be passing by the main entrance on floor 1. On floor 2 the
number is 800 cars at the entrance and so on, and on floor 5 it is 200 cars. More cars through a DPO
(entrance or exit point) will increase the risk of miscount. A miscount on one floor will affect the accuracy
of available spaces for up to two floors.
If the main entrance DPO is faulty and does not detect cars driving in, only this floor’s display shows a
wrong number of available spaces.
If a car leaves floor 1 to go to floor 2 and the DPO on this floor is defective, the number of available spaces
on floor 1 and 2 will be affected. The reason is that this DPO works as an exit DPO for floor 1 and entrance
DPO for floor 2.
Delineation
If there is no delineation between the entrance and the exit lanes, experience shows that vehicles will
always drive in the middle of the lane, which might cause activation of more than one DPO. If this happens,
the system will count the same vehicle twice and the number of available spaces will be decreased or
increased by two.
However, if there is only one DPO, it is possible to drive in the middle of the lane and still be counted
correctly. Still, this solution has a downside. If two cars pass one another in the DPO area, the system will
count only the first car that activates the sensor. The other car stays undetected. In this situation, it is not
possible to tell if the system will increase or decrease the number of available spaces by one.
Car speed is yet another issue. The sensor’s built-in filter can be used to correct this problem. If filter 1 is
chosen, the sensor will detect cars driving up to 45 km/h. If filter 4 is chosen, cars that drive less than 8
km/h will be detected.
Speed bumps
For safety and correct counting, we recommend speed bumps together with the DPO.
We recommend always driving slow through the counting system to increase the accuracy. Filter 4 and
filter 6 in the counting system represent a speed no more than 8-16 km/h and that is a proper speed.
However, speed bumps will help prevent bumper-to-bumper driving, thereby highly increasing the
accuracy, especially during rush hours.