Street lighting is first of all about safety and proper image of the illuminated places.An important component of street lighting are the control devices, they largely determine the safety and operating costs.
The main task of the control is to turn on the lighting in the evening – when the natural light is too weak and turn it off in the morning – when there is enough light.An additional control task can be to reduce lighting power when conditions allow.
The control system can also provide a range of other information such as information about the current state of lighting, or failure messages.
Standards related to road lighting define quite precisely the situations in which the intensity of road lighting can be reduced, and even more precisely define the levels of light intensity, or rather luminance assigned to specific categories of roads.However, there is no guidance on the levels at which outdoor lighting should be switched on in the evening and switched off in the morning.Lighting managers rely on their own experience in this matter.Determining the control parameters it should be remembered that many accidents, especially in the autumn and winter, occur at dusk, unfortunately these are often accidents involving pedestrians.
When choosing a lighting control system, consider factors such as:the extent of the lighting installation, the number of lighting cabinets, the installed power and the annual energy consumption.Then determine the basic functions that should be performed by the control system.
A properly selected control system should provide benefits in two primary areas, the first being the reduction of energy costs for lighting, and the second being ease of management and maintenance.Estimating savings in energy consumption is relatively simple.Benefits in the area of management and maintenance are difficult to predict.An important step in the decision-making process is to estimate the cost of purchase and subsequent operation of the control system.It is necessary to take into account the possible costs of licenses, connectivity and, above all, future maintenance costs with particular emphasis on the post-warranty period.It is a good idea to do cost accounting for the entire projected life.The purchase costs are one-time costs and can be covered by possible subsidies, while other costs, less visible at the time of purchase, will remain for the entire period of use.It’s good to be aware of this when making purchasing decisions.
Projected operating costs should be compared to the expected performance of the system.
This mode of reasoning must be repeated for each control system considered.
Bringing the offered solutions to a common denominator will enable a rational comparison of them and will allow to choose the optimal solution.