CP3 version 3003
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Anarchist drivers
Driving across the DPO and diagonally activate the sensors, is another problem we have experienced in the
Carpark systems. Such behaviour is no problem in systems with only one DPO. If, however, there is more
than one DPO, the counting system will not accept this as a valid signal and the car will not be detected.
A counting system with many DPOs, no delineation and perhaps parked cars on the lanes beside the
sensors will never be a reliable and accurate system. Resetting the system more often, perhaps every day,
will be necessary. And, of course, resetting is possible with the MZC. A built-in scheduler can reset the
system at a specific time selected by the system administrator. An appropriate time could be during the
night-time when there are no or only few cars in the carpark system. Inaccuracies are unavoidable, but if
the system is reset every 24 hours, the inaccuracy will not increase (if there are no parked cars when the
system is reset). The automatic reset will always show maximum available spaces. Besides that, the
counting system has a built-in offset. This function makes it possible to reset the system when cars are
parked in the system. If the parking has 1000 spaces in total and there are 45 cars parked at the time when
the installer performs a reset, it is possible to select 45 as an offset in the automatic reset function. This
function is also described in the software installation manual.
Sensor mounting
The sensor must always be mounted to point directly towards an even and hard surface. The surface must
not be sand, rubble or grass. For instance, concrete or asphalt can reflect an ultrasonic signal of acceptable
quality back to the sensor. Make sure that water, snow or objects do not disturb the signal, since faulty
activations may be a result.
The sensor must be mounted on a solid surface protected against shocks. Any movement of the sensor may
cause faulty activations resulting in miscounts. Therefore, the sensor should be mounted directly in the
ceiling. However, if the ceiling is more than 2.5 m from the floor, it will be necessary to lower the sensor to
the required level using conduits or rail mounting. Of course the mounting must be completely robust and
shock-free.