There are two issues that influence the room temperature measured:
1. the measuring principle: the UC… plastic cover perceives also the radiant part of the temperature, and changes it into increased temperature of the sensor body. If a black ball temperature sensor (such as http://products.domat-int.com/en/passive-temperature-sensors/178-pendulum-room-temperature-sensor.html) is used for reference purposes, a temperature close to what the UC… says would be measured. Most of the reference probes only measure the air temperature.
2. Another problem, of course, may be heat dissipation within the device. This is compensated by factory-set correction (which can be changed to fit the situation). But it already is set up so as to compensate the dissipation.
Please do check one thing: if the power supply voltage is higher than about 27 V, the internal overvoltage protection responds, and cuts its peaks. It may be a small voltage difference, but it is turned into heat, which then influences the whole inside of the UC… inclusive the sensor part. So an oscilloscope can be used to check if the power supply is a pure sine (OK), or a sine with cut peaks (not OK). An alternative is a thermal camera which shows if the heat is generated at the processor only, or also at the overvoltage protection element (a small component at the power supply teminals of the UC…).
Another reason may be the (warm) air coming from the piping in the wall where your cables are pulled, but this is not so probable. However, you can check if the pipes are sealed. We had such problem at one of the sites some time ago.
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As part of the expansion of application platforms for the Merbon system, we have established cooperation with the company Wago and launched the stations with the Merbon runtime under the name wall.
Room units with external temperature sensor.
Runtime, or program which runs the application engineered by a programmer, executes the main activity of a PLC. It may be implemented on various hardware platforms. The platforms have different properties, such as processor computing power, operation memory and flash memory size, types and number of serial communication ports, integrated analog and digita inputs / outputs, etc. These properties determine the functionalities which a particular platform is able to support.
We would like to invite you to visit our stand at the LIGHT + BUILDING 2020 fair, which is located in Frankfurt. As every year, we introduce our product and system news.
We would like to invite you to visit our stand at the AMPER 2020 fair, which will take place at the Brno Exhibition Center. As every year, we introduce our product and system news.
On 18 March, Domat will join forces again with the Faculty of Electrical Engineering and Communication in Brno.