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Suntracer pro from Elsner Elektronik records brightness, GPS signal, wind speed and direction, precipitation, temperature, humidity and pressure and thus makes an important contribution to professional building automation. In the RS485 system, a terminal device such as a PLC, PC or a microcontroller reads this data and processes it further.
Light intensity and position of the sun are essential for energy-optimised sun shading control. Suntracer RS485 pro determines the brightness with five sensors that are aligned differently. Regardless of whether the sun is low or high, the highest currently measured brightness value is always output. This results in a realistic light measurement during the course of the day. The position of the sun for precise blind control is calculated in the unit from the received GPS signal.
The outdoor temperature is the basis for heat and frost protection functions. In addition, the perceived temperature is calculated taking into account wind strength and humidity. Humidity is measured and the dew point is calculated, which helps to predict condensation. The air pressure is also recorded.
Rain and snow are detected to protect awnings and for window control. The measuring elements are heated so that dew and fog do not trigger a precipitation message.
The real highlight of the weather station, however, is the measurement of wind speed and wind direction by ultrasound.
The ultrasonic wind measurement method and its advantages
The shape of the Suntracer RS485 pro ensures a turbulence-free air flow. The wind measurement is carried out on two horizontal sections offset by 90°. On each section, two signals are sent in the opposite direction shortly after each other. The speed and direction of flow are determined from the differences in the running time of the two axes.
An advantage of the process is the short reaction time, even with gusts and peak values. Changes of direction or strength are directly visible in the change of the measured value on the data bus. In this way can blinds, awning cloth and other wind-sensitive components be moved quickly into a safe position.
If the wind direction is known in the building control system, the façades exposed to the wind can be specifically protected and costly wind damage avoided. The automatic shading and ventilation continues on the sides of the building facing away from the wind. Similar to the sun protection control, a compass direction profile is designed for the wind alarm and individual façade sections are controlled in a targeted manner. The often conflicting goals of protecting building elements and technology, offering the user comfort and opportunities for co-determination and optimising the building‘s energy efficiency are thus reconciled in the best possible way.
Form follows Function – and convinces in design
The unusual shape of the Suntracer pro got the German Design Award 2020. The filigree, ring-shaped structure of Suntracer RS485 pro is very resistant, as it is reinforced on the inside by stainless steel elements.
In order to capture the weather unadulterated, Suntracer RS485 pro is mounted on a mast on the roof of the building. The supplied mast extension ensures a distance between sensors and surrounding building elements. It can be clamped to a vertical mast or a horizontal pipe or screwed to a beam.
For correct measurement results the ring must be aligned horizontally. A small spirit level, which is included with the device, helps with this.
Info link to Suntracer RS485 on manufacturer homepage: https://www.elsner-elektronik.de/en/rs485-wetterdata/