Temperatures of non-metallic materials between 0 °C and 500 °C can be measured by non-contacting means with the infrared transmitter TIR-SA. The emission value of the target must be known for accurate measurements. The TIR-SA is adjusted at the factory for the emission value of most non-metallic materials. Thus for example the temperatures of plastic, wood, textiles, glass, liquids or foodstuffs can be easily measured. The TIR-SA is small, rugged and, with its stainless steel case, also suitable for service in rough service environments. The sensor can be delivered with three different measuring ranges each with three different outputs. The relationship of the diameter of the measuring dot to the test distance is 1 : 5 for the optics.