The counting and communication hardware in our Telraam S2 Outdoor unit is the same as in the standard Telraam S2 sensor, therefore the registration process on telraam.net is the same as it is for the indoor devices. Below we provide guidelines about the physical installation process of the device and its potential power supply components.
Location
The device must have a clear, unobstructed view towards the street. There should be no trees, large bushes, shelters, banners, poles, advertising panels, or other objects blocking a significant part of the view.
WARNING! Always consult with the local authorities regarding the rules and regulations around the usage of public space and infrastructure before starting an installation!
Distance from the road, and height
The optimal installation height equals the horizontal distance between the device and the middle point of the monitored street section, including any footpath, cycle path, and other areas around the vehicular traffic lanes which are meant to be monitored. This will ensure that the device is looking at a 45 degree angle to the middle of the area.
An optimally installed Telraam S2 Outdoor sensor - 45 degree angle to the centre of the counting area, and no road surface in the blindspot
In case this height is unachievable due to the available infrastructure, a height not resulting in a central viewing angle outside of the 30-60 degree range is acceptable.
A device placed too low or too close to the road will result in objects being blocked by each other or not fully being visible in the field of view, while a device placed too high or too far from the road will present a too steep viewing angle for the AI algorithm and the small size of pedestrians and cyclists will result in a decreased counting accuracy for these modes. We do not recommend placing the sensor more than 30 meters away from the furthest sidewalk, or 50 meters from the furthest traffic lane (in case the monitoring of pedestrians at that distance is not required).
The device has a blind spot extending to ~10 degrees from straight downwards, therefore it cannot count objects that are right underneath it. This blindspot distance is approximately 0.5 meters when the device is installed at 3 meters height, and 1.75 meters when installed at 10 meters. This should be taken into account when choosing the distance from the edge of the monitored area.
A minimum height of 3 meters is suggested to prevent vandalism.
The region of interest (ROI) setting upon the registration of the installed Telraam sensor will provide options to fine-tune the monitoring area.
A practical example: if the area of interest (including sidewalk, cycle path, etc.) is 10 meters wide, and your mounting pole is 2 meters from the edge of the monitored area (so 2 + 10 / 2 = 7 meters from the middle of the monitored area), then the optimal height is 7 meters.
This is over the minimum required of 3 meters,
the furthest object will be 2 + 10 = 12 meters from the sensor which is under the required 30 (50) meters,
and at 7 meters the blind spot is 1.23 meters, which is less than the 2 meters from the edge of the monitoring area, meaning that the installation is optimal.
Note: a height of 12 meters would result in a steeper 60 degree downward viewing angle (this is the maximum acceptable height), and 4 meters would result in a shallower 30 degree downward angle (lowest acceptable height).
Mounting the Telraam S2 Outdoor unit
There are two mounting anchors on the backside of the unit's housing. Metal (long term) or plastic (short term) cable ties can be used to lock the unit in place around a mounting pole/structure. Inox cable ties are recommended as the weight of the unit is 1.5 kg. Examples can be found here.
Metal cable ties guided through the mounting anchors and around a pole, ready to be tightened
Power supply
The Telraam S2 Outdoor unit requires DC power. A built-in DC convertor will transform any DC power input between 12-24 V to the appropriate voltage.
WARNING! Do not connect the Telraam S2 Outdoor unit to any power source outside of the 12-24 V range as this might damage the electronics!
Power is supplied through a standard DC 5.5 x 2.1 mm barrel jack connector. Ensure your power supply is compatible with the (female) barrel jack at the end of the cable from the Telraam S2 Outdoor unit. The cable comes pre-mounted with a junction box for a watertight connection.
To connect:
Push the male connector through the nut and rubber gaskets.
Secure the connection inside the junction box.
Firmly tighten the nuts on the junction box to complete the installation.
If no local power source is available, we recommend using an off-the-shelf solar-battery kit for off-grid operation.
