Smart Building – Smart Control

Many smart buildings use motion and light sensors to reduce energy consumption of the buildings lighting. Understanding the pitfalls in design and installation leads to lower installation costs and lower energy consumption.


The introduction of a sensor into every luminaire can have a positive effect on the total cost of installation and help reduce the buildings energy consumption.

Common Motion Sensor Issues


Achieving accurate detection

The placement of motion sensors in room is important, however due to cost (limiting the number of sensors used), installation (the cost of installing more than one sensor) or placement of the sensors, the way the sensors operate may be undesirable.

False Detection

Installation too close to a doorway can trigger a false detection as people walk past. This results in unoccupied rooms being turned on, effectively wasting power. Additionally, the lights will remain on until the idle time has expired because of the false trigger.


Late Detection

In some cases, obstructions on the ceiling grid caused by air-conditioning vents, smoke detectors, speakers or other lighting, means the placement of the sensor is not ideal. This can lead to an installation where the occupant is detected well after they have entered the room.

The Solution – One Sensor per Fitting

Sensor per Fitting

As the lighting is installed in a uniform grid arrangement the placement of the sensors is reasonably guaranteed and would typically be located above workspaces. Where previously an employee siting in a corner or a person behind furniture, large monitors and plants would not have been detected, a sensor per fitting arrangement helps to ensure movement detection at all workspaces.

Common Light Sensor Issues


Daylight harvesting

Modern buildings utilise daylight harvesting to save energy, using light level sensors to detect the lighting level and dynamically reduce the artificially lighting levels to maintain a desired lux level. The effectiveness of daylight harvesting depends on the arrangement and setup of the light level sensors.


The placement of the light level sensors and the control of the lighting are often met with cost issues. To save costs installers use a minimal number of light level sensors, and control groups, leading to a poor outcome, as changes to the environment close to the sensor can affect light fittings placed further down the row in a room.

Too dark/light

If an occupant closes a blind next to the sensor, the lighting further down the building has its brightness increased, reducing the energy saving benefits. Even more problematic is when an occupant seated away from the sensor closes their blind, the sensor does not detect any change leaving the light levels too low in some areas.

Dependant placement

The light level sensors position is quite often dictated by where the motion sensor is installed, close to doors and workstations, as they normally are contained in the same product. The result is that the sensors are often installed in the centre of an area and not directly under the lights needing control.

The Solution – One Sensor per Fitting

A sensor per fitting

An installation where a light level sensor is installed into every luminaire is an ideal solution. When controlled together in a group, all light level sensors must be satisfied before the light levels are reduced, which ensures the light levels do not drop below the desired minimum. If an installer is looking for the best energy savings, individual control on a per fitting basis allows for every light fitting to achieve their optimal light levels without over lighting other areas.

However, having a light level sensor in every luminaire using traditional control methods can be problematic due to bandwidth constraints on a DALI line, which most control systems are not able to properly deal with and therefore a better solution is required.

The better Solution – Zencontrol Smart driver

To solve all the above issues, zencontrol has developed a smart driver built on IEC62386 V2 and other smart technologies. zencontrol has perfected “sensor per-fitting” technology with its Smart driver. Its an LED driver for connected luminaires designed to make the most out of leading technologies in control, automation and connectivity.

Developed as a factory fitted, standardized, plug & play driver, it’s a IEC62386 V2 compliant solution that offers a lower overall cost of installation, reduced purchase price and lower commissioning cost linked to each individual light fitting and sensor, now operating as a single unit.

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