The strict requirements of the Swiss Accreditation Service SAS were successfully met: The pressure calibration laboratory now complies with standard SN EN ISO/IEC 17025 and has been given the accreditation number SCS 0156. Every measuring instrument ages due to mechanical, chemical or thermal stress. The accuracy of the measured values therefore changes over time, which cannot be prevented. Trafag, however, offers their customers most accurate products, since the measuring equipment is regularly calibrated in accordance with the standards of internal quality assurance. This is the only way to reliably guarantee the required precision of the measuring equipment.
The measuring equipment is thus calibrated against a reference instrument, or a so-called «standard», i.e. a target/actual comparison is carried out. According to QA, all operating equipment in production, such as pressure regulators or electrical measuring instruments, are checked for accuracy annually or as required.
The measuring equipment used achieves five to ten times the accuracy of the test object, i.e. Trafag's products. In this way, Trafag's pressure transmitters can be produced to the accuracy specified in the data sheets. For Trafag, the advantage of having its own calibration laboratory is that there is no transport with potential transport damage and a resulting loss of accuracy for the measuring equipment, a core element in the production of pressure transmitters. It also results in a great saving of time. If the measuring equipment is tested by an external calibration laboratory, it will not be available for up to three months.
With internal testing, the interruption can be reduced to a few hours, or eliminated completely by using replacement equipment. Currently, there is only a limited number of accredited testing laboratories in Switzerland that are authorized to perform pressure calibrations.