INFICON Composer Elite Gas Concentration Monitor - Manual (Page 131)

8 - 3
PN
07
4-
56
6-
P1
B
Composer Elite Operating Manual
Concentration drift / offset Reference Zero was
performed before Acoustic
Sensor was completely
purged with a pure carrier
gas (refer to
section
4.1.10, What Happens if
the Reference Zero is
Improperly Set?, on page
4-8
).
Concentration offset is
equal to the residual
precursor concentration at
the time the Reference
Zero was performed. Thoroughly purge
Acoustic Sensor with pure
carrier gas and then
perform Reference Zero
(refer to
section 3.2,
Calibration, on page 3-2 ).
Large barometric pressure
change without performing
Reference Zero. Depends on magnitude of
barometric pressure
change. Perform Reference Zero
(refer to
section 3.2,
Calibration, on page 3-2 ).
Reference Zero performed
at inappropriate time. Depends on magnitude of
temperature change after
Reference Zero was
performed. Wait for STEADY and AT
TEMP indicators to appear
and then allow additional
time for maximum
temperature stability
before setting Reference
Zero.
Change of process
pressure. Refer to section 4.1.6,
What is the Effect of
Pressure Variation?, on
page 4-4
.
Perform Reference Zero
(refer to
section 3.2,
Calibration, on page 3-2 ).
Change of process flow. Refer to section 4.1.7,
What is the Effect of Flow
Variation?, on page 4-5
.
Perform Reference Zero
(refer to
section 3.2,
Calibration, on page 3-2 ).
Table 8-1 FMEA (continued)
Symptom Possible Cause Effect on Concentration
Accuracy Remedy