Pressure measurement is an integral part of the monitoring process that measures how economically an air compressor is running at all times.
The rising cost of energy means that each unit within a factory must always be running at optimal performance, and for air compressors that means increasing or decreasing the compressor load to meet the changing demand for compressed air throughout the factory lines.
For this purpose it is becoming more and more common to install “air management” systems, which monitor the performance indicators and the different stages of the various air compressors which are connected to the compressed-air supply grid – making sure that each compressor runs at the right power level at exactly the required time. To do this effectively, pressure sensors are needed to monitor the output pressure of each compression stage, and with that come many challenges:
Air compressors are prone to high levels of vibration, which means that a pressure sensor installed directly onto the body (housing) of a compressor is subjected to correspondingly high levels of vibration. This can lead to the failure of many pressure sensors installed in such a way, unless they are pre-designed with such demanding working environments in mind.
Another major issue faced by pressure sensors installed on air compressors is the elevated ambient temperature – the compressors moving parts and their very tight clearances lead to increased temperatures within the housing, which can result in temperature errors that present themselves on the output of a pressure sensor and lead to inaccurate power calculations.
Self-hating that compressor designers go for to overcome these issues is installing pressure sensors (and other similar instruments) remotely on a side panel next to the main housing of the compressor – this reduces exposure to both vibration and high ambient temperatures, and also protects the pressure sensors from the harmful effects of these conditions. Having a compact pressure sensor with a dual pressure thread (an external thread to fasten the sensor onto the side panel, and an internal thread to connect the air hose) is a helpful tool when designing such a solution.
Note
Further information on pressure sensors can be found on the WIKA website.