Agilent Technologies 34401A manual Input error =, 100, Ppm of input error =, 000,000

Chapter 8 Specifications

To Calculate Total Measurement Error

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 shows the range error applied to the multimeter’s 24-hour dc voltage specification.

Range	Input Level	Range Error		Range
		(% of range)	Error Voltage
10 Vdc	10 Vdc	0.0004	≤	40 ∝V
10 Vdc	1 Vdc	0.0004	≤	40 ∝V
10 Vdc	0.1 Vdc	0.0004	≤	40 ∝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	⋅	100
	Input Signal Level
ppm of input error =	Total Measurement Error	⋅	1,000,000
	Input Signal Level

Error Example Assume that a 5 Vdc signal is input to the multimeter on the 10 Vdc range. Compute the total measurement error using the 90-day accuracy specifications: ± (0.0020% of reading + 0.0005% of range).

Reading Error	= 0.0020%		⋅	5 Vdc	= 100 ∝V
Range Error	=	0.0005%	⋅	10 Vdc	= 50 ∝V
Total Error	=	100 ∝V + 50 ∝V			= ± 150 ∝V
					= ± 0.0030% of 5 Vdc

= ± 30 ppm of 5 Vdc

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