IEC 62059-32-1-2011 pdf free download – Electricity metering equipment – Dependability – Part 32-1: Durability – Testing of the stability of metrological characteristics by applying elevated temperature.
The stability of metrological characteristics is one important aspect of durability.
This part of IEC 62059 specifies a method for testing the stability of metrologicalcharacteristics of electricity meters，by operating a test specimen at the upper limit of thespecified operating range of temperature, voltage and current for an extended period.
Functional performance other than the accuracy of energy measurement is out of the scope ofthis standard.
Note,that from the results of this test,no conclusion can be drawn for the length of periodduring which the stability of the metrological characteristics will be maintained when the meteris operated under usual conditions.
This International Standard is applicable to all types of electricity meters in the scope of lECTC 13.
2Normative references
The following referenced documents are indispensable for the application of this document.For dated references,only the edition cited applies. For undated references, the latest editionof the referenced document (including any amendments) applies.
IEC 60068-2-2:2007,，Environmental testing – Part 2-2:Tests – Test B: Dry heat
IEC 62052-11:2003，Electricity metering equipment (AC) – General requirements,tests andtest conditions – Part 11 : Metering equipment
IEC 62053-21:2003，Electricity metering equipment (a.c.) -Particular requirements – Part 21:Static meters for active energy (classes 1 and 2)
3Terms and definitions
For the purposes of this document, the terms and definitions in lEC 62052-11 as well as thefollowing apply.
3.1
durability
the ability of an item to perform a required function under given conditions of use andmaintenance, until a limiting state is reached
NOTE A limiting state of an item may be characterized by the end of the useful life, unsuitabiity or any economicor technological reasons or other relevant factors.
4General
The test procedure consists of:
.initial measurements, see Clause 5;
operational conditioning at the maximum temperature, voltage and current of the specifiedoperating range, see Clause 6. During the conditioning, intermediate measurements aretaken, see Clause 7;
.recovery – see Clause 8 – and final measurements,see Clause 9.
The test shall be performed on (one of) the meter(s) submitted for type testing (meter undertest, MUT).
During the conditioning, the MUT shall not exhibit any irregular behaviour concerning energymeasurement and registration.This shall be verified as specified in Clause 7.
ln addition，after conditioning and recovery，the change of the percentage error，whencompared to the initial measurements,shall not exceed the limits specified in Clause 9.Toverify this，the percentage error shall be measured, as specified in Clause 5, beforeconditioning and following the recovery period.
lf the MUT passes the test,this gives a reasonable level of confidence that the meter typetested is free from serious design errors and material flaws that may prevent it frommaintaining its specified accuracy for the period of use estimated by the manufacturer.
NOTE For this estimation, the acceleration factor determined according to lEC 62059-31 can be used.
5 Initial measurements
The percentage error of the MUT shall be measured – using the test output of the MUT andappropriate test equipment – at the following test points:
• value of voltage: U n ;
• value of current for direct connected meters: 0,1 I b , I b and I max ;
• value of current for transformer operated meters: 0,05 I n , I n and I max ;
• value of power factor for meters for active energy: cos φ = 1 and cos φ = 0,5 inductive;
• value of power factor for meters for reactive energy: sin φ = 1 and sin φ = 0,5 inductive.
The accuracy test conditions shall be as specified in the relevant type test standard.
6 Conditioning
The MUT shall be exposed to the elevated temperature according to IEC 60068-2-2 as follows:
• test Be: dry heat for heat-dissipating specimens with gradual change of temperature that are required to be powered throughout the test;
• air velocity: low preferred (see IEC 60068-2-2, 4.2);
• temperature: the upper limit of the operating temperature range specified by the manufacturer;
• duration of the test: 1 000 h;IEC 62059-32-1 pdf download.