Teledyne API Model 300M CO Analyzer Instruction Manual, 04033, Rev. A
8.3 Zero/Span Checking
It is recommended that the Model 300M be checked daily for zero and span drift.
With the Automatic Zero/Span Check and Remote Zero/Span Check features of the Model 300M, daily zero and span checks are easy.
For Automatic Zero/Span Check and Remote Zero/Span Check to be effective, it is necessary that the analyzer have the Zero/Span valve option. This option includes the two
Operating instructions for Automatic Zero/Span Check and Remote Zero/Span Check are described in Sections 3.3 through 3.6.