Measurement Uncertainty Analysis – Power Reference Level Test
Measurement Introduction
B-8
Agilent E4416A/E4417A Service Guide
Resistance
The uncertainty of the resistance measurement on the 3458A DMM is given from:
with: -
Conditions: - 1 Year Cal and temperature va/- 5°C without ACAL
Reference: - 3458A Operating Manual Appendix A
For 1k
Ω
scale the specified accuracy is;
with: -
1ppm of R 0.1ppm of Range per
°
C (temp coefficient Tcal ±5
°
C)
and, 3ppm of Reading (for factory traceability)
Therefore,
Repeatability
To verify the overall repeatability of the measurement, the test was repeated 20 times,
using the same DUT. For each test cycle, the Power Reference Level Test and the
Power Reference Level Adjust tests, were carried out; at no point during these tests
was the 1mW on the DUT adjusted. The thermistor was disconnected and
reconnected between each test with the sensor position rotated each time. The results
for this evaluation are shown in Table B-1.
Error = (ppm of r ppm of range) + (temperature coefficient) + (factory traceability)
10ppm of r 0.5ppm of range
U R
( )
200
10
5
3
+
+
(
)
×
1000000
-----------------------------------------------
1000
0.5
0.5
+
(
)
×
1000000
-----------------------------------------------
+
0.0036
0.0010
+
(
)
0.0046
Ω
=
=
=
4402serv.book Page 8 Tuesday, October 14, 2003 3:18 PM
Summary of Contents for E4418B
Page 19: ...1 Specifications 4402serv book Page 1 Tuesday October 14 2003 3 18 PM ...
Page 37: ...2 Performance Tests 4402serv book Page 1 Tuesday October 14 2003 3 18 PM ...
Page 69: ...3 Adjustments 4402serv book Page 1 Tuesday October 14 2003 3 18 PM ...
Page 81: ...4 Theory of Operation 4402serv book Page 1 Tuesday October 14 2003 3 18 PM ...
Page 95: ...5 Replaceable Parts 4402serv book Page 1 Tuesday October 14 2003 3 18 PM ...
Page 119: ...6 Troubleshooting 4402serv book Page 1 Tuesday October 14 2003 3 18 PM ...
