IEC 62053-22-2020 pdf download-Electricity metering equipment – Particular requirements.
7.3 Measurement uncertainty The requirements, test conditions and procedures, and acceptance criteria of IEC 62052-1 1 :2020 apply. 7.4 Meter constant The requirements, test conditions and procedures, and acceptance criteria of IEC 62052-1 1 :2020 apply. 7.5 Initial start-up of the meter The requirements, test conditions and procedures, and acceptance criteria of IEC 62052-1 1 :2020 apply. 7.6 Test of no-load condition The requirements, test conditions and procedures, and acceptance criteria of IEC 62052-1 1 :2020 apply. 7.7 Starting current test The requirements, test conditions and procedures, and acceptance criteria of IEC 62052-1 1 :2020 apply. 7.8 Repeatability test The requirements, test conditions and procedures, and acceptance criteria of IEC 62052-1 1 :2020 apply. 7.9 Limits of error due to variation of the current When the meter is under the reference conditions given in IEC 62052-1 1 :2020, 7.1 , the percentage errors shall not exceed the limits for the relevant accuracy class given in Table 3. If the meter is designed for the measurement of energy in both directions, the values in Table 3 shall apply for each direction. If the meter is intended for multiple connection modes, the accuracy testing results are valid only for the connection modes tested and cannot be used to claim accuracy for other, untested connection modes.
When testing poly-phase meters for compliance with Table 3 requirements for single phase loads, the test current shall be applied to each measuring element in sequence, while all the phase voltages shall remain balanced. 7.1 0 Limits of error due to influence quantities Tests and test conditions given in IEC 62052-1 1 :2020, 7.1 apply. If the meter is rated for multiple connection modes, the accuracy requirements apply for each of the connection modes. All tests of effects of influence quantities shall be performed in one connection mode selected to exercise the complete metrological capability of the meter. When the current and the phase displacement (power factor) are held constant as specified in Table 4, and any single influence quantity is applied one at a time, with the meter otherwise operated at reference conditions as specified in IEC 62052-1 1 :2020, 7.1 , the additional variation in percentage error relative to the intrinsic error shall not exceed the limits specified for the relevant class indexes given in Table 4. The variation in percentage error induced by the influence quantities may vary depending on the value of the test current. The variation in percentage error in Table 4 is given for the specified values or ranges of the test current but the testing should be performed at the recommended values of test current given in Table 4.