Fluke ScopeMeter 19 B Series, Руководство по обслуживанию

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Performance Verification
4.6 Scope Input A&B Tests
4
4-9
Note
The vertical accuracy test can also be done with dc voltage. This method is
advised for automatic verification using the Fluke Met/Cal Metrology
Software. For each sensitivity range you must proceed as follows:
1.
Apply a +3 divisions voltage, and adjust the voltage until the trace is at
+3 divisions. Write down the applied voltage V1
2. Apply a -3 divisions voltage, and adjust the voltage until the trace is at
-3 divisions. Write down the applied voltage V2
3. Verify that V1-V2 = 6 x range
±
(1.5% + 0.04 x range).:
Example for range 10 mV/div. (range/div figure doubles because 2
measurements V1 and V2 are done for one accuracy check):
The allowed V1 - V2 = 60 mV
±
(0.015 x 60 + 0.08 x 10)
= 60 mV
±
(0.9 + 0.8) = 60 mV
±
1.7 mV
4.6.2 Input A&B DC Voltage Accuracy Test
WARNING
Dangerous voltages will be present on the calibration source
and connecting cables during the following steps. Ensure that
the calibrator is in standby mode before making any connection
between the calibrator and the test tool.
Proceed as follows to verify the automatic dc voltage scope measurement:
1.
Connect the test tool to the 5500A as for the previous test (see Figure 4-3).
2. Select the following test tool setup:
•
Recall the created SETUP 1 (see section 4.4.3): press ,
RECALL
,
select
SETUP 1
, press
RECALL SETUP
.
•
Press , then press
INPUT A OPTIONS ...
•
Select
Polarity: Normal | Bandwidth: 10 kHz (HF Reject)
•
Press , then press
INPUT B OPTIONS ...
•
Select
Polarity: Normal | Bandwidth: 10 kHz (HF Reject)
•
Press to clear the softkey menu, and to see the full 8 divisions screen.
3. Using change the time base to select manual time base ranging, and lock the
time base on 10 ms/div.
4. Using and move the Input A and B ground level (zero icon in the left
margin) approximately to the center grid line.
5. Using and select manual vertical ranging and set the Input A and B
sensitivity range to the first test point in Table 4-2.
The sensitivity ranges are indicated in the left and right lower display edge.
6. Set the 5500A to source the appropriate dc voltage.
7. Observe the readings (
1.A
and
2.B
) and check to see if it is within the range shown
under the appropriate column.
Due to calibrator noise, occasionally OL (overload) can be shown.
8. Continue through the test points.
9. When you are finished, set the 5500A to 0 (zero) Volt, and to Standby.