The temperature measurement is of great importance in many industrial applications. It is distinguished between two different measurement principles: 1. contactless and 2. media contacting. A contactless measurement is carried out via infrared radiation. It allows a measurement of temperatures up to 1800°C, as no periphery of the system, such as the probe, requires contact to the medium or object. As a result these devices are often used in forges, rolling mills or generally in steel processing companies. The media contacting measurement is usually performed in combination with a PT100 thermal resistance, which is then connected to the evaluation electronics or display devices. Areas of application for these system versions can be found in cooling systems, storage tanks, exhaust systems, extraction or ventilation systems.