Analytical Industries GPR-1800 IS ATEX Trace PPM Oxygen Transmitter - Manual (Page 14)

Advanced Instruments, Inc
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Example 1: As illustrated by Graph A, any error during a span adjustment at lower end of the scale, e.g.,
20.9% (air) on a 100% full scale range, would be multiplied by a factor of 4.78 (100/20.9) when making
measurements close to 100% O2. Conversely, an error during a span adjustment close to the top end of the
range, e.g., at 100% is reduced proportionately for measurements of oxygen concentrations near the bottom
end of the range.
Graph B represents a constant error over the entire measuring range. This error is generally associated with
the measuring e.g., LCD and or calibrating devices, e.g., current simulator or current/voltage measuring
devices.