Sifos Technologies PowerSync PSA100, Техническое справочное руководство

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PowerSync Analyzer Reference Manual
March 9, 2010 Sifos Technologies page 112
7.2. PSE Conformance Testing – High Power PSE’s
PSA Software Version 3.4 includes six alternative
PSE Conformance Tests
that are applicable only to High Power
PSE ports. These are:
Test Name Test Description
pwrup_inrush_2
802.3at compliant PSE’s should behave identically to 802.3af PSE’s during inrush. However,
many pre-standard High Power PSE’s were developed without this limitation and are capable
of inrush currents well above the 450 mA maximum limit allowed as of Draft 3.0 of 802.3at.
pwrup_pwrcap_2
PSE Port Power Capacity test for PSE’s with output power capacity in the 20 to 39 Watt band.
pwrup_maxi_2
PSE Short Circuit Load Compliance test for PSE’s with current limiting thresholds (
I
lim
) in the
600mA to 1000 mA band.
pwrup_overld_2
PSE Transient Load Response test for PSE’s with maximum overload (
I
cut
) at or below 685
mA.
pwrdn_overld_2
PSE Overload Shutdown test for PSE’s with overload cutoff currents (Icut) in the range of 530
to 690 mA.
pwrdn_v_2
PSE Error Delay test for PSE’s with current limiting thresholds (Ilim) in the 600mA to 1000 mA
band.
Like their 802.3af counterparts, these tests can be run individually or sequenced automatically from the PSA Interactive
GUI and from PowerShell. Each test produces output results and parameters that are exactly analogous to their
corresponding 802.3af test counterparts. Each test, where applicable, supports display of voltage and current
waveforms collected as part of the parametric
analysis during testing. (See Figure 7.3.)
Test limits for each parameter associated with the
High Power tests are derived from Draft 4.0 of
802.3at which was submitted to the IEEE 802.3
Working Group in January, 2009. These test limits
in some cases may not be finalized.
PSE Conformance Testing can be sequenced to the
standard Sifos 802.3af Conformance Test Report
spreadsheet for limit checking and statistical analysis.
Some parameters outside the normal 802.3at limit
boundaries will be flagged as “Fail” or “Info”.
Another key difference between the 802.3af tests and their High Power counterparts is the need within the High Power
tests to search for device-specific thresholds for cutoff current (
I
cut
) and overload limiting current (
I
lim
) thresholds. The
tests will typically take slightly longer to execute since these unspecified limit thresholds will vary according to PSE
implementation and perhaps across PSE ports that are tested. Since the PSE Conformance Tests make no assumptions
regarding these thresholds, the tests are ready to use with proprietary implementations of 2-Pair High Power PSE’s.
All other PSE Conformance Tests will run using the standard 802.3af version and are not affected by the differences
between 802.3af compliant PSE’s and pre-802.3at high power PSE’s.
It should be noted that full coverage of Type-2, high power PSE’s under 802.3at cannot be fully achieved by the PSA-
1200 and will eventually require the enhanced testing resources of a newer generation version of the PSA-1200.
7.3. PSE Conformance Test Reporting
The standard PSE Conformance Test Report spreadsheet for the PowerSync Analyzer will report results from both
normal 802.3af and High Power PSE testing that is sequenced from PSA Interactive or PowerShell.
Figure 7.4 shows a sampling of test results from a 4-port PSE running a full suite of PSE Conformance Tests including
the six new high power tests utilizing PSA Port Combiners.
Figure 7.3
. Ilim Current Trace from pwrup_maxi_2 Test.