Keysight Technologies E4417A User Manual

Measurement Uncertainty Analysis - Power Reference Level Test C
Keysight E4416A/E4417A Power Meters Service Guide 151
Uncertainty Equation
General form of uncertainty equation is:
Hence,
Assuming that there is no correlation exists between the 8 input variables.
Voltage Measurements Uncertainty
Since the manufacturer's data is used to determine the standard uncertainty, the
analysis used is the Type A method.
The 3458A DMM Uncertainty is calculated with reference to the Appendix A of the
3458A Operating Manual.
A normal distribution is assumed, as the 3458A Manual has not specified the type
of distribution used on the measurement.
Both V
0
and V
1
values are calculated by subtracting V
ref
from V
comp
as measured
at the output of the 432A using a 3458A DMM. The approximate values of V
comp
and V
ref
for no power (V
0
) and for 1 mW power (V
1
) are 5 V with the DMM on the
10 V scale.
For the 3458A DMM, the specified accuracy for the 10 volt scale is: 8ppm of
Reading + 0.5 ppm of Range
u
2
y() c
2
iu
2
x
i
() 2 c
i
c
j
ux
i
x
j
,()
ji1+=
N
∑
i1=
N
∑
⎝⎠
⎜⎟
⎜⎟
⎛⎞
+
i1=
N
∑
=
u
2
1mW()CV
0
uV
0
() ⋅
2
– CV
0
uV
0
()
⋅
2
CV
comp
uV
comp
()
⋅
2
CR u R()
⋅
2
… ++ ++
CCF u CF() ⋅
2
CM
s
uM
s
()
⋅
2
C
Rep
uRep()
⋅
2
C
Drift
uDrift()
⋅
2
++ +

Keysight Technologies E4417A Specifications

General

Brand	Keysight Technologies
Model	E4417A
Category	Measuring Instruments
Language	English