Keysight Technologies E4417A User Manual

C Measurement Uncertainty Analysis - Power Reference Level Test
160 Keysight E4416A/E4417A Power Meters Service Guide
Combined Standard Uncertainty (uc(y))
Expanded Uncertainty
The expanded uncertainty is: U= 3.030 mW, as a percent of
1.000 mW: U = 0.303%
Table C-2 Combined Standard Uncertainty
Symbol Source of Uncertainty Value Probability
Distribution
Divisor Ci Ui/mW
U(V
0
) Two Voltage measurements
on a
3458A DMM
69.65 μW Rectangular 1.732
2.129x10
-04
V/Ω
0.009
U(V
1
) Two Voltage measurements
on a
3458A DMM
69.45 μW Rectangular 1.732
1.224x10
-02
V/Ω
0.491
U(V
comp
) Voltage measurement on
3458A DMM
49.25 μW Rectangular 1.732
−1.245x10
-02
V/Ω
0.354
U(R) 4 wire Resistance
measurement on
3458A DMM
0.0046 Ω Rectangular 1.732
−4.727x10
-06
W/Ω
0.013
U(CF) Calibration factor for
Thermistor
0.002 Normal 2
−9.696x10
-04
W
0.970
U(M
s
) Mismatch between the DUT
and the Thermistor
0.0012 U shaped
−9.454x10
-04
W
0.802
U(Drift) Drift of 8478B Thermistor 0.0006 Normal 2
1.00x10
-03
W
0.3
U(Rep) Repeatability of the complete
measurement
0.057 μWSigma 1 1 0.057
U(c) Combined Uncertainty Normal 1.429
U
[a]
Expanded Uncertainty k = 2 Normal 2.859
[a] Using Keysight's standard 95.5% confidence the coverage factor is k = 2.00
2

Keysight Technologies E4417A Specifications

General

Brand	Keysight Technologies
Model	E4417A
Category	Measuring Instruments
Language	English