Water-cooled absolute pressure sensors, M14, for high temperature gas pressure measurement (0 … 5, 0 … 10 bar) / 4049B

The piezoresistive pressure sensors of Type 4049B with integrated water cooling are capable of continuous high-temperature operation. Available in absolute pressure ranges of 5 and 10 bar they are designed for use in various applications but specifically for exhaust pressure measurement without the use of additional water-cooled adapters. These pressure transducers use a Wheatstone bridge implanted in a silicon measuring element to generate an electrical signal, which is proportional to the applied pressure. The measuring element is situated in an oil-filled cavity seperated by a steel diapraghm. This core element is placed within a cooling jacket whereby the internal temperature can be suitably managed and is nearly independent of the applied hot gases. This approach allows the sensor to be exposed to gas temperatures in excess of 1100°C. Due to constant water cooling thermal effects are minimized. Therefore, the overall accuracy is improved. Further performance improvements are achieved using digital compensation, which reduces thermal effect to a minimum without sacrificing signal bandwidth. The digital compensation technique further allows monitoring of the sensor temperatures (with amplifiers of Types 4665B and 4624A).