Agilent Technologies 34420A User Manual page 283

Ratio Error
Example
Chapter 8
To Calculate Total Measurement Error
This example demonstrates how to compute the total measurement error
when using the Ratio Function. Assume a ratio measurement is made
with the following conditions:
Channel 1, 5 V input on the 10 Volt range
Channel 2, 10 mV input on the 10 mV range
To compute the total measurement error using the 90-day accuracy
specifications:
Ratio Error % = Channel 1 accuracy in % + Channel 2 accuracy in %
Channel 1 Reading Error % = 0.0020%
Channel 1 Range Error % = 0.0004%
Total Channel 1 Error % = 0.0020% +
Channel 2 Reading Error % = 0.0040%
Channel 2 Range Error % = 0.0002%
Total Channel 2 Error % = 0.0040% +
Ratio Error % = 0.0028%
5 V
Ratio = = 500 ± 0.0070% = 500 ± 0.035
10
mV
For Ratio Measurements, if both input channels use the same range, use
0 for the % of reading error.
284
Range
Reading
= .0028%
0.0008%
Range
Reading
= .0042%
0.0002%
+
0.0042% = .0070%
10
= .0004% = .0008%
5
10 mV
= .0002% = .0002%
10 mV