What are the Challenges of Low Pressure Calibration?
Calibration of Instruments is important in monitoring pressure readings accurately. This can be tough, especially in environments where working conditions require low-pressure (.2 to 5 PSI) measurement, such as in medical instrumentation, environment pollution control, clean rooms, pharmaceutical manufacturing and various other industries.
Within such complex environments, the accurate pressure reading with the help of a differential pressure transmitter is essential to maintaining low-pressure applications.
Even the slightest differences in pressure can cause discrepancies which can affect the accuracy of the instrument under calibration. Therefore, low-pressure calibration can be a challenging endeavour.
Low-pressure calibration applications include maintaining a controlled environment, controlling energy systems, and monitoring equipment types such as HVAC. However, there are several other factors that the industry and other experts need to consider to maintain low-pressure calibration.
Problems that may arise during low-pressure calibration are:
1. Generating A Stable Low-Pressure Environment
A low-pressure calibration setup is different from its high-pressure counterparts. A sealed and controlled low-pressure environment is influenced by many internal and external factors such as the climate condition, direct air-flow, humidity control, pressure and temperature within the room caused by instruments, workers, and computers.
Factors like these make it challenging to keep the environment within compliance.
Moreover, the rising cost of energy poses yet another challenge to maintain pressure, especially in low-pressure environments.
Furthermore, generating and maintaining a stable pressure area can be difficult because even the smallest changes in pressure can cause significant pressure gradients for low-pressure calibrations. With a pressure drop, it becomes challenging to calibrate accurately.
2. Temperature of the Instrument
Despite the insulation to prevent air kicking of from heating or cooling and subsequently changing the pressure in a controlled environment.
Often it is difficult to ward off the heat produced by the instrument being used, for example, a motorized piston or electronics that alters the pressure within the instrument and the calibrator.
Although temperature shift during high-pressure calibration doesn’t impact the gauge pressures reading, even the slightest change in temperature during low-pressure calibration can cause a temperature-induced error and degrade the results’ accuracy.
3. Disturbances In The Ambience
In a low-pressure environment, vibrations caused by construction or traffic in the adjacent areas can significantly impact the pressure reading.
Although these vibrations can hardly be felt, the instruments with a lower tolerance can detect disturbances in the surrounding that inversely affect the calibration accuracy.
For instance, a DP transmitter may give an error in a weighing machine scale because of the vibrations caused outside lab or a room.
Additionally, technicians’ work tasks or any other movement like foot traffic in a low-pressure area affect the instrument’s tolerance or the ambiance.
So, workers in low-pressure calibration systems should be aware to minimize disturbances.
Moreover, it is recommended to calibrate in the corner of a room than the centre and use vibration isolators to improve results.
When carefully eliminated from the calibration environment, these factors can improve the reliability and accuracy of results. An optimal environment setup is necessary to overcome the challenges posed by low-pressure calibration. For more info, Get in Touch with Us!