AMETEK MX CTSH - Manual (Page 19)

California Instruments Revision H 19
User Manual MX Series CTSH Compliance Test System
2.4.2 EUT Category Abbreviations used
The following connection types are supported using the abbreviations shown in the table:
Abbreviation Meaning
CSPNBTPE Connection Single Phase & Non Balanced Three Phase Equipment
CBTPE Connection Balanced Three Phase Equipment
CBTPEUSC Connection Balanced Three Phase Equipment Under Specified Conditions.
If different Sce values apply to each category EUT, they will be shown between brackets immediately
following these abbreviations in the Limit drop down control.
2.4.3 IEC 61000-3-12 Test Times
The test time used to run a Harmonics test is determined by the nature of the EUT. Under the 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 are:
Table 2-5: Harmonics Test Times
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.
You can increase the test time up to 24 hours if needed. The test period needs to be set long enough to
cover the entire operating cycle of the unit under test. This is particularly important for the transitory
harmonics tests. Avoid setting the test time longer than necessary as it only decreases your test
throughput.