Agilent Technologies 34420A, Руководство пользователя

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Understanding the " % of range" Error . The range error compensates
for inaccuracies that result from the function and range you select. The
range error contributes a constant error, expressed as a percent of range,
independent of the input signal level. The following table ilustrates the
range error applied to the meter’s 24-hour dc voltage specification.
Range Input Level
Range Error
(%of range)
Range Error
Voltage
10 V 10 V 0.0001
≤
10
µ
V
10 V 1 V 0.0001
≤
10
µ
V
10 V 0.1 V 0.0001
≤
10
µ
V
Total Measurement Error . To compute the total measurement error,
add the reading error and range error. You can then convert the total
measurement error to a "percent of input" error or a
"ppm (part-per-million) of input" error as shown below.
% of input error
=
Total Measurement Error
Input Signal Level
∗
100
ppm of input error
=
Total Measurement Error
Input Signal Level
∗
1,000,000
Total Measurement
Error Example
Assume that a 5 Vdc signal is input to the meter on the 10 Vdc range.
To compute the total measurement error using the 90-day accuracy
specifications:
±
(0.0020% of r 0.0004% of range).
Reading Error
=
0.0020%
∗
5 V
=
100
µ
V
Range Error
=
0.0004%
∗
10 V
=
40
µ
V
Total Error
=
100
µ
V
+
40
µ
V
=
±
140
µ
V
% of input error
=
±
140
µ
V
5 V
∗
100
= ±
0.0028% of 5 V
ppm of input error
=
±
140
µ
V
5 V
∗
1,000,000
=
±
28 ppm of 5 V
Chapter 8
To Calculate Total Measurement Error
282