AMETEK MX CTSL - Manual (Page 68)

User Manual MX-CTSL Compliance Test System
California Instruments Revision J 68
The exact EN 61000-3-2:1998 standard text is as
Start here
follows:
“..equipment shall be deemed to be Class D if, under the test
conditions given in Annex C, the input current
of each half period - referred to its peak value i
pk
- is
Yes
Balanced
Three Phase
Equipment?
waveshape
within the
envelope shown in the following figure for at least 95 % of the
duration of each half period; this implies that waveforms
having small peaks outside the envelope are No considered
to fall within the envelope. The center line M, coincides with the
peak value of the input current.”
A device that does not meet these class D
requirements defaults to a class A device and
tested against the class A limits.
The flowchart shown in Figure 5-2 can be used
determine the class of the device to be tested.
When selecting EN 61000-3-2:1998 mode with a
Portable
Power
Tool?
No
Lighting
Equipment?
No
Yes
Yes
CLASS B
CLASS C
should be
to
Class D
device, the CTS Software will display the current wave
shape and the special waveform template. The P<600W
& special
percentage that fails within the template is waveshape displayed
as well. If the waveform is not class D, the user will be
given an indication. The test can still be run
In Class A testing, the special waveform check is
performed to prevent a “False Positive”. Yes
Motor
No
Driven?
CLASS D
however.
also
If the CTS software indicates that the current waveform
does not meet the Class D requirements, the user should
switch to Class A instead.
Figure 5-2: EUT Class Determination
Flowchart
5.3.2 Dynamic Class C and D Limits
Harmonic current limits for Class D are a function of the EUT power level. This poses an interesting
problem, especially if the device has a fluctuating power draw pattern. This means the test limits change
with the power consumption of the EUT. While there is some discussion in the IEC community regarding
the practicality of using such dynamic test limits, the CTS software is fast enough to dynamically recalculate
the test limits applied to the current harmonics for each acquisition window of 16 signal periods. As such,
the CTS system fully implements the IEC standard with respect to class D.
The same issue applies to the third harmonic limit for Class C products, which is a function of the
fundamental current and power factor (
λ
). The CTS software determines the fundamental current and
power factor of the load for each acquisition window and dynamically determines the correct 3
rd
harmonic
current limit for Class C devices.
If you select to test to Amendment 14, you will have to enter the manufacturer rated power for Class D
(TV's, PC's and PC Monitors) or the fundamental current and power factor for Class C (lighting products)
instead. The rated values will be used to calculate the Class C and D limits as long as the actual measured
values do not differ from the rated values by more than 10 % during the test.
No
CLASS A
Yes