Fluke 6135A/PMU, Руководство оператора

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6135A/PMU
Operators Manual
9-4
Output connector on the rear panel of the 6105A Master Unit (rear-panel access
required). Reconnect the 6105A Master Unit to STU BNC connection via the tee
piece.
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. Connect the external trigger input of the oscilloscope to the AUX OUT B connector
on the rear panel of the Timing Unit (access from the left hand side panel of the
calibration system).
5. Start the Client software and establish a connection with the PMU.
6. Select Test > Customize and Run Single Tests > Steady State Tests.
7. In the General Parameters, Test Timing menu, set Test Duration to 5 seconds.
8. In the Test Parameters menu set:
•
Input Frequency: to nominal frequency (50 or 60 Hz)
•
Phase Shift: -90 ˚
•
Voltage and Magnitude Index: 100 %
•
Current and Magnitude Index: 100 %
•
Harmonic Index: 0
•
Interharmonic Index: 0
9. Select Run Test. The oscilloscope will not trigger until the AUX OUT B signal
negative edge (
T
0
) at the start of the test. The Voltage Positive Sequence TVE results
will be plotted on the Client software as the test progresses.
10. After the trigger, measure the time from the 1 PPS positive edge to the positive edge
of
Ref
p
. The edges will be slightly distorted due to imperfect impedance match of the
oscilloscope to 6105A Master Unit
Ref
p
output, measure between the sharp initial
transitions of the edges. Note that if the
Ref
p
edge occurs before the 1 PPS edge the
time is negative.
11. Record the measured time as “Physical time difference” in Table 9-2.
12. The test passes if the time difference is less than ±1 µs.
13. Remove the oscilloscope external trigger input connection from AUX OUT B.
Verify the Accuracy of the Timing Inputs
This test measures the accuracy of the time inputs STU_T0 and STU_TRefp data input to
the mathematical model.
1.
Open the file:
<userprofile>\Documents\Fluke PMUCal\System\Logs\T0 time
stamp.txt
.
2. The value “Diff” (3
rd
parameter) is in seconds. Record Diff in the “Model time
difference” in Table 9-2. If the absolute time of STU_Refp is earlier than STU_T0
the time is negative.
3. Check that the difference between “Physical time difference” and “Model time
difference” is less than 525 ns. Note that 525 ns is equivalent to less than 0.02 %
TVE.
Table 9-2. Time Differences
Difference Result Limit
Physical time difference: (A) ±1 µs
Model time difference (Diff): (B) ±1 µs
A - B ±525 ns