AMETEK CTS 3.0 - Manual (Page 23)

User Manual Compliance Test System 3.0
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basis for the limit calculation of Class-D (Class- C). Thus, a “rated power” of 150 Watt for example,
will yield a third harmonic limit of 150 x 3.4 = 510 mA. Similarly, a rated fundamental current of 0.4
Amp, and a rated PF of 0.98 for an electronic ballast will result in a third harmonic limit of 0.4 x 0.3
x 0.98 = 117.6 mA. Thus, the amendment requires that an automated compliance test system
must allow the user to enter this rated power or rated current. Also, the test system must verify the
power (fundamental current and PF) because thes
e “rated vales” as declared by the manufacturer
must be within +/- 10 % of the actual values. If not, the actually measured values are to be used
for the limit calculation. The method to measure these actual power, fundamental current and PF
differ from th
e “average method” used in existing test systems, and of course differ also from the
“dynamic limit method”.
The Pass/Fail criterion is given above. The “10 % of the time over 100 % of the limits” no longer
exists. The average harmonic level during the whole test must simply be below the limit, and
individual values in each acquisition window (after 1.5 sec filtering) must be below 150 % of the
limit. There is also an extra allowance for the higher harmonics from H
21
- H
39
.
The CTS fully supports and implements Amendment 14.
2.3.3 IEC 61000-3-2:2000 Test Time
Under the new test standard, four test times (observation periods) are allowed depending on the
nature of the EUT. All are aimed at ensuring repeatability of test results when tests are performed
under the same conditions and on the same test system. Repeatability for this purpose is defined
as results that are within 5 %. Available observation periods shown in the table below.
Type of equipment
behavior Observation period
Quasi-stationary T
obs
of sufficient duration to meet the requirements for
repeatability.
Short cycles (Tcycle < 2.5
min) T
obs
> 10 cycles (reference method) or Tobs of sufficient duration
or synchronization to meet the requirements for repeatability.
'Synchronization' means that the total observation period is
sufficiently close to including an exact integral number of
equipment cycles such that the requirements for repeatability are
met.
Random T
obs
of sufficient duration to meet the requirements for
repeatability.
Long cyclic (Tcycle > 2.5
min) Full equipment program cycle (reference method) or a
representative 2.5-min period considered by the manufacturer as
the operating period with the highest total harmonic content.
Table 2-2: Harmonics Amendment 14 Test Times