Agilent Technologies E4418B, Service Manual

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Measurement Uncertainty Analysis – Instrument Accuracy Test
Measurement Introduction
A-8 Agilent E4416A/E4417A Service Guide
By using the DMM Uncertainties calculated previously the worst case voltage and
corresponding power errors can be calculated.
Sensitivity Coefficients Ci:
The partial derivatives of the measurement equation Y = f(MV, TSE) equal 1.
TSE is derived from a number of readings taken by the test station to characterize the
cabling, connectors noise and so forth. Therefore no measurement equation exists to
differentiate. It is a measured value of magnitude.
Hence:
The DMM Measured Voltage also has a sensitivity coefficient equal to 1. As with the
TSE the Measured Voltage is not computed from an equation. Is it a real value that the
DMM actually measures.
Hence:
Power Setting
(mW)
Applied Volts
DMM Error on
Range Standard
Uncertainty (uV)
Worst Case
Voltage Error on
Range (%)
Worst Case
Power Error on
Range
0.001 0.14493mV <1.371uV 0.946% 0.00946uW
0.01 1.4493mV <1.371uV 0.0946% 0.00946uW
0.1 14.493mV 1.371uV 0.00946% 0.00946uW
1 144.93mV 6.09uV 0.00420% 0.042uW
10 1.4588V 56.8uV 0.00389% 0.389uW
100 15.6V 148.8uV 0.00095% 0.95uW
C
TSE
TSE d
d
TSE 1
= =
C
M V
MV
d
d
MV 1 = =
4402serv.book Page 8 Tuesday, October 14, 2003 3:18 PM