Any devices used for the measurement of pressure will lose accuracy over time. When carrying out critical applications, it is vital to ensure that any and all instrumentation used is correctly calibrated in order to ensure that they are measuring as accurately as possible. Many instruments include pressure sensors, for example controllers and indicators.
The Importance of Calibration
Most measuring instruments and devices will require regular calibration in order to ensure that they are operating within the tolerance of their factory specifications. Every measurement category and application will have its own specified national and international standards, to which it must adhere.
Calibration is achieved by comparing the pressure of a device or instrument under pressure (also known as DUP) to its particular tolerance standard or specification. It is important to carry out regular calibration of any device with pressure sensors, as doing so will reduce the risk of taking readings with a higher probability or range of error.
The Benefits Of Pressure Calibration
In taking the time to carry out regular pressure calibration of your devices, you can expect to enjoy a range of benefits. Regular calibration will ensure standardisation across your measurements, which thereby helps to ensure safety and optimal efficiency.
How Often Should You Calibrate Your Instruments?
Although it is important to regularly calibrate pressure measurement instruments, the precise interval of time between each calibration will vary for different devices. For example, the level of accuracy required for measurements will dictate the frequency of calibration. The higher the degree of accuracy required, the shorter the interval between each pressure calibration.
It is typically the zero point which drifts over time, although there may also be what is known as "span" drift. The higher the quality of instrument, the longer it will take for drifting to occur. The user guide or manual for your pressure measurement instruments will usually give you an insight as to how frequently you may expect to have to calibrate, but the normal interval is anywhere from every 95 days to once a year.
How To Carry Out Pressure Calibration
There are several ways in which pressure calibration may be carried out. These include in a laboratory, at a test bench, or even on site or in the field. The method of pressure calibration will usually be down to the device in question and personal choice, unless official accreditation is required. In the latter case, the calibration must be carried out by an approved body. For the highest accuracy in calibrating the device, a laboratory setting is the best choice.
To calibrate a pressure measurement device, you will need a regulated source of pressure, a relevant pressure standard, an output for reading the DUT (device under test), and accessories to connect the DUT to both the regulated source of pressure and the pressure standard.