Fluke 6135A/PMU, Руководство оператора

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Performance Verification
Procedures
9
9-5
Verify Step Timing Accuracy
This test checks the latency of the step change in the 6135A analogue output with respect
to the 1 PPS. The objective is to compare the time of the step with respect to the 1 PPS
with the time stamp STU_T0. Voltage phase steps of ±10˚ with transitions near the zero
voltage cross over are used for the tests. It is only necessary to check the step on each of
the three voltage outputs to check the time error of the trigger from the STU and the
delay in the 6135A trigger circuits. These time errors are common to all voltage and
current outputs. Correct functioning of the current outputs can be confirmed by reference
to the results of step tests on a PMU. Suitable transducers such as wide band voltage
divider and current shunt with greater than 1 MHz bandwidth are required to make
measurements beyond those described below.
XW
Warning
To prevent possible electrical shock, fire, or personal injury: Do
not attempt to connect or disconnect any electrical connections
to the UUT if a test is running. Always treat the Input/Output
Panel connectors, L1, L2, and L3, as if they have hazardous
voltages present.
The 6105A TRIG OUT signal is used to trigger this measurement. The settings described
below are suitable for measurements where the attached PMU nominal voltage is 70 V or
100 V. If the nominal voltage is greater than 100 V, set the nominal value to 70 V in the
Client software PMU personality screen. The PMU results will not be correct but that
does not matter for the purpose of these measurements.
1.
Set up oscilloscope as follows:
Table 9-3. Oscilloscope Setup
Set Ch1 Ch2 Horizontal Trigger
Coupling DC DC DC
Per division 10 V 1V 100µs
Position -2 Div 0 Div Centre Negative edge
2.
Connect Ext Trig 1of the oscilloscope to the TRIGGER OUTPUT connector on the
rear panel of the 6135A System (rear-panel access required).
3. Connect Channel 2 of the oscilloscope to the 1 PPS connector on the Calibration
System Input/Output panel (right side of the system).
4. Start the Client software and establish a connection with the PMU.
5. Select Test > Customize and Run Single Tests > Step Tests.
6. In the General Parameters, Test Timing menu set Test Duration to 3 seconds.