AS IEC 60060.2:2018 pdf free.High-voltage test techniques Part 2: Measuring systems.
4 Procedures for qualification and use of measuring systems
4.1 General principles
Every approved measunng system shall undergo initial testing, followed by performance tests (periodic, see 4.2) and performance checks (periodic, see 4.3) throughout its service life. The initial tests consist of type tests (performed on a component or system of the same design) and routine tests (performed on every component or system).
The performance tests and checks shall prove that the measuring systems can measure the intended test voltages within the uncertainties given in this standard, and that the measurements are traceable to national and/or international standards of measurement. The system is approved only for the arrangements and operating conditions included in its record of performance.
A major requirement for a converting device, a transmission system. and a measuring instrument used in a measuring system is stability within the specified range of operating conditions so that the scale factor of the measuring system remains constant over long periods.
The assigned scale factor is determined in the performance test by calibration. The user shall apply tests given in this standard to qualify their measuring system(s). Alternatively, any user may choose to have the performance tests made by a National Metrology Institute or by a Calibration Laboratory accredited for the quantity to be calibrated. In all cases, the user shall include the test data into the record of performance.
Any calibration shall be traceable to national and/or international standards. The user shall ensure that any self-made calibration is performed by competent personnel using reference measuring systems and suitable procedures.
NOTE Calibrations performed by a National Metrology Institute, or by a laboratory accredited for the quantities calibrated and reporfed under the accreditation, are considered traceable to national andlor international standards.
4.2 Schedule of performance tests
To maintain the quality of a measuring system, its assigned scale factor(s) shall be determined by periodic performance tests. The interval between performance tests shall be based on evaluation of past stability of the measuring system. It is recommended that the performance test should be repeated annually, but the maximum interval shall not be longer than five years.
NOTE Long intervals between performance tests can increase the risk of an undetected change in the measurement system
Performance test shall be made after major repairs to the measuring system and whenever a circuit arrangement that is beyond the limits given in the record of performance is to be used.
When a performance test is required because a performance check shows that the assigned scale factor is no longer valid, the cause of this change shall be investigated before the performance test is made.
4.3 Schedule of performance checks
Performance checks shall be made at Intervals based on the recorded stability of the measuring system as shown in the record of performance. The interval from the last performance test or the last performance check shall not be longer than one year.
For a new or repaired measuring system, performance checks shall be made at short intervals to demonstrate its stability.
No reference method is identified for the performance checks because the required accuracy is less than that required for performance tests.
4.4 Requirements for the record of performance
4.4.1 Contents of the record of performance
The results of all tests and checks, including the conditions under which the results were obtained, shall be kept in the record of performance (stored in paper format or electronically if permitted by quality systems and local laws) established and maintained by the user. The record of performance shall uniquely identify the components of the measuring system and shall be structured so that performance of the measuring system can be traced over time.
The record of performance shall comprise at least the following information:
• General description of the measuring system.
• Results of type and routine tests on the converting device, transmission system(s) and measuring instrument(s) and, if performed, on the measuring system.
• Results of subsequent performance tests on the measuring system.
• Results of subsequent performance checks on the measuring system.AS IEC 60060.2 pdf download.