Professional Weather Data Collection with Suntracer KNX pro

The weather station for the KNX building bus system records all relevant weather data for building control, including temperature, brightness, precipitation, wind speed, wind direction, humidity and pressure.

Temperature (risk of frost), precipitation (moisture) and wind in particular are elementary for the protection of shades and furnishings. The corresponding alarm functions can be configured directly in the KNX application of Suntracer KNX pro so that shades are retracted timely and windows are closed.

The wind measurement is a special highlight. It is also responsible for the unusual shape of the weather station. Two ultrasonic measuring sections measure both wind speed and wind direction. If the wind direction is known in the KNX system, the facades exposed to the wind can be specifically protected and costly wind damage can be avoided. In the meanwhile, the automatic shading and ventilation is continued on the sides of the building facing away from the wind.

An advantage of the ultrasonic measuring method is the short reaction time, even during gusts and peaks. Changes in direction or strength are directly visible in the change of the measured value on the data bus. Only in this way can hangings of blinds, awning cloth and other wind-sensitive components be quickly and reliably brought into a safe position.

The wind measurement is wear-free and all other parts of the Suntracer KNX pro are also very low-maintenance.

From many years of experience with weather stations of various designs, Elsner Elektronik knows that coarse dirt that impedes the measurement rarely occurs.

For this reason, you will not find a conventional programming button on the Suntracer KNX pro. Addressing on the KNX bus is triggered via a magnetic contact.

A magnetic telescopic rod is included with the device.

The filigree-looking device is very resistant, as it is reinforced inside by stainless steel elements. In order to record the weather without distortion, the Suntracer KNX pro is designed to be mounted on a pole on the roof of the building. The mounting situation influences the measurement considerably. The influences to be measured must reach the device unhindered.

Surrounding buildings or planting can deflect and shield wind, sun or rain and create their own microclimate in which temperature and humidity are also distorted.

The supplied mast extension provides distance between sensors and surrounding structures. It can be clamped not only to a vertical mast, but also to horizontal pipes or screwed to a beam or wall.

For a correct wind measurement, the ring must be aligned horizontally. A small spirit level, which is included with the device, helps with this.

The semi-transparent plastic of the ring measures the brightness for the sun protection control.

In order to record the sun as completely as possible during the course of the day, five differently aligned light sensors are used. In this way, the sun protection can be optimally controlled at all times. 12 façades can be automated with the Suntracer KNX pro, each with individual settings and limit values.

The weather station calculates the position of the sun for shading automation from the data of the integrated GPS receiver. The compass direction of the façade, shadows cast by neighbouring buildings or trees, the shadow edge up to which the sun is allowed to shine into the room and the slat position of blinds are taken into account in the façade control. For energy-optimised automation, the room temperature can also be evaluated, provided the data is available from the KNX system.

The sun can thus be used as a cost-free heat source in winter if the shading is only closed after the desired temperature has been reached.

The sensors for temperature and humidity are installed in the well-ventilated base of the weather station. The bus line and auxiliary voltage are also connected there.

The absolute humidity can be output as well as information on the comfort field according to DIN 1946-2, which describes when the relationship between temperature and humidity is perceived as pleasant.

The dew point calculated by the weather station helps to avoid condensation. A control function for the cooling medium of air conditioning systems is also integrated.

The so-called summer compensation also intervenes in the cooling of the building and contributes to energy-conscious operation. When outside temperatures are high, the setpoint temperature for room cooling is raised along a characteristic curve. In this way, the difference between the heat outside and the cooled interior does not become too great. In addition to the energy-saving benefits, many people also find this pleasant.