7.1.2
Factory setting
During zero point adjustment or reference point adjustment, the SO
2
/CO
2-
ratio cannot
be used for compliance monitoring as long as the maintenance signal is active.
The ratio value describes the SO
2
/CO
2
ratio. If the CO
2
value <1 Vol% drops towards
zero, the ratio value would become infinitely large.
To avoid misinterpretation, the MARSIC300 is factory set so that the ratio value auto‐
matically jumps to -999 as soon as the CO
2
value is <1 Vol%.
The SO
2
/CO
2
ratio returns to normal after the adjustment is completed. The mainte‐
nance signal goes out and measuring operation can be continued when the initial state
is reached.
Measuring Mode
Premeasuring
Mode
Zero Point Adjustment/
Reference Point Adjustment
Measuring Mode
CO
2
approx. 5-7%
CO
2
< 1 Vol%
–999.9
SO
2
/CO
2
ratio
SO
2
/CO
2
ratio
CO
2
Maintenance signal active
Adjustment starts.
Adjustment ends.
7
ANNEX
22
A D D E N D U M T O O P E R A T I N G I N S T R U C T I O N S | MARSIC300
8026470/AE00/V1-0/2021-04 | SICK
Subject to change without notice