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发表于 2008-12-23 16:16:39
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由于公司的文件估计有什么特征可以识别的，未免麻烦，只好贴一部分A1:2008的内容上来
3 Definitions
Add the following new definitions:
3.21
repeatability of results of measurements
closeness of the agreement between the results of measurements of harmonic currents on the
same equipment under test, carried out with the same test system, at the same location,
under identical test conditions
[IEV 394-40-38, modified 1)]
3.22
reproducibility of results of measurements
closeness of the agreement between the results of measurements of harmonic currents on the
same equipment under test, carried out with different test systems under conditions of
measurement intended to be the same in each case
[IEV 394-40-39, modified]
NOTE The test system and test conditions are assumed to fulfil all normative requirements in the standards.
3.23
variability of results of measurements
closeness of the agreement between the results of measurements of harmonic currents on
different samples of the same type of equipment under test, having no intentional differences,
carried out with different test systems under conditions of measurement intended to be the
same in each case
NOTE 1 The test system and test conditions are assumed to fulfil all normative requirements in the standards.
NOTE 2 In the context of this standard, the meaning of the terms can be summarized as follows:
Term Meaning
Repeatability Same EUT, same test system, same test conditions, repeated tests
Reproducibility Same EUT, different but normative test systems, different but normative test conditions
Variability Different EUTs of the same type, having no intentional differences, different but
normative test systems, different but normative test conditions
6.2.2 Measurement procedure
Replace, in the penultimate paragraph, 6.2.3.4 by 6.2.3.5.
6.2.3 General requirements
Replace Subclause 6.2.3.1 by the following:
6.2.3.1 Repeatability
The repeatability (see 3.21) of the average value for the individual harmonic currents over the
entire test observation period shall be better than ±5 % of the applicable limit, when the
following conditions are met:
– the same equipment under test (EUT) (not another of the same type, however similar);
– identical test conditions;
– the same test system;
– identical climatic conditions, if relevant.
NOTE This repeatability requirement serves the purpose of defining the necessary observation period, see 6.2.4.
It is not intended to serve as a pass/fail criterion for the assessment of compliance with the requirements of this
standard.
Insert the following new Subclause 6.2.3.2 and renumber existing Subclauses 6.2.3.2 to
6.2.3.4 as 6.2.3.3 to 6.2.3.5 accordingly:
6.2.3.2 Reproducibility
The reproducibility (see 3.22) of measurements on the same EUT with different test systems
cannot be definitively calculated so as to apply to all possible combinations of EUT,
harmonics meter and test supply, but can be estimated to be better than ± (1 % + 10 mA),
where the 1 % is 1 % of the average value of the total input current taken over the entire test
observation period. Therefore, differences in results which are less than that value of current
are deemed negligible, but in some cases a higher value may occur.
For the avoidance of doubt in such cases, test results, obtained at different locations or on
different occasions, that show that all the relevant limits are met shall be accepted as
demonstrating compliance, even though the results may differ more than the values for
repeatability and reproducibility, given above.
NOTE The variability (see 3.23) of measurements on different EUTs of the same type, having no intentional
differences, can be increased by practical component tolerances and other effects, such as possible interactions
between the characteristics of the EUT and the measuring instrument or the power supply. The results of these
effects cannot be quantified in this standard, for the same reasons as for reproducibility. The second paragraph of
6.2.3.2 also applies in the case of variability.
A regulatory concession in respect of limit values to allow for possible variability is recommended but outside the
scope of this standard.
Annex A – Measurement circuit and supply source
In Figures A.1 and A.2 amend Note 1 as follows and add the following Note 3:
NOTE 1 ZS and ZM are not specified, but must be sufficiently low for the requirements of Clause A.2 to be met.
This is checked by measuring the properties of the supply voltage at the point of connection of the EUT to the
measurement equipment. More information can be found in IEC 61000-4-7.
NOTE 3 For some types of equipment, such as single-phase uncontrolled rectifiers, the harmonic amplitudes vary
greatly with the supply voltage. To minimize variability, it is recommended to maintain the voltage at the point of
connection of the EUT to the measurement equipment to 230 V or 400 V within ±1,0 V, evaluated over the same
200 ms observation window, used for harmonic assessment.
Annex C – Type test conditions
C.7 Test conditions for vacuum cleaners
Replace in the last line 6.2.3.3 by 6.2.3.4.
C.10 Test conditions for information technology equipment (ITE)
Replace the entire existing text by:
C.10.1 General conditions
ITE (including personal computers) which is marketed without 'factory-fitted options' and
without expansion slot capabilities is tested as supplied. ITE, other than personal computers,
which is marketed with 'factory-fitted options' or has expansion slots, is tested with additional
loads in each expansion slot that result in the maximum power consumption attainable using
the “factory-fitted options” specified by the manufacturer.
For the testing of personal computers with up to 3 expansion slots, load cards configured for
the maximum permitted power for each expansion slot shall be added to each respective
expansion slot. For the testing of personal computers with more than 3 expansion slots,
additional load cards shall be installed at the rate of at least one load card for each group of
up to 3 additional slots (i.e. for 4, 5 or 6 slots a total of at least 4 load cards shall be added.
For 7, 8 or 9 slots a total of at least 5 load cards shall be added, etc.).
Modular equipment, such as hard drive arrays and network servers, are tested in their
maximum configuration.
In all configurations, the use of additional load cards shall not cause the total DC output
power available to be exceeded.
NOTE 1 The above does not mean that multiple options of the same type, such as more than one hard drive,
should be fitted, unless that is representative of the user configuration, or the product is of a type (such as
Redundant Arrays of Inexpensive Disks (RAID)) for which such a configuration is not abnormal.
NOTE 2 Common load cards for expansion slots such as PCI or PCI-2 are configured for 30 W but may be
adjusted as industry standards change.
Emission tests shall be conducted with the user’s operation controls or automatic programs
set to the mode expected to produce the maximum total harmonic current (THC) under normal
operating conditions.
Power saving modes which may cause large power level fluctuations shall be disabled, so
that all, or part, of the equipment does not automatically switch off during the measurements.
For ITE systems designed for use with a manufacturer-supplied power distribution system,
such as one or more transformers, UPS or a power conditioner, compliance with the limits of
this standard shall be met at the input supplied from the public low-voltage distribution
network.
C.10.2 Optional conditions for measuring emissions of IT equipment with external
power supplies or battery chargers
For IT equipment with external power supplies or battery chargers, manufacturers may
choose
• either to test the whole equipment according to C.10.1 (General conditions),
• or to test the equipment by measuring the AC input power and the harmonic emissions of
the associated power supply or battery charger according to 6.2.2 with the DC output side
loaded by a resistive load, provided that, with the resistive load applied, the peak-to-peak
ripple voltage across the load is not greater than 5 % of the DC output voltage.
The resistance value of the load shall be such that the active power dissipated in the load is
equal to the DC output power rating, or, if that is not available, to the DC output voltage rating
multiplied by the DC output current rating marked on the power supply/battery charger unit.
Power supply/battery charger units whose AC input power measured according to 6.2.2 under
the above load conditions is 75 W or less are deemed to conform without further testing, as
specified in Clause 7. |
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