wilks InfraRan - Troubleshooting

Wilks Enterprise Inc InfraRan Instruction Manual
30
20.0 Troubleshooting
1. Number Displayed at the End of a Zero Cycle
At the end of a zero cycle (initiated with Analyze->Rezero->Zero), the number
displayed following ZERO = is the voltage from the first detector. This value should be
between 1 and 4.5 V.
If it is:
Between 0.5 and 1 V and the sample is known to be anesthetic-free air then cell
contamination, probably due to dust or lint, is likely. Useful measurements should still
be possible for a short time but instrument noise can be expected to increase. The
analyzer should be returned to Wilks Enterprise for service and recalibration as soon as
possible.
Between 0.1 and 0.5 V and the sample is known to be anesthetic-free air then either the
cell has suffered severe contamination or some optical components have moved due to
a severe mechanical shock. Instrument noise will be high and measurements will be of
questionable value. The analyzer must be returned to Wilks Enterprise for repair and
recalibration.
Between 0 and 0.1 V and the sample is known to be anesthetic-free air then either
some optical components have been dislodged by a severe mechanical shock, optical
components (source, detector, gas cell) or electronic components have failed. Useful
measurements will not be possible. The analyzer must be returned to Wilks Enterprise
for repair and recalibration.
2. Negative Readings for an Anesthetic are Displayed
Negative readings for an anesthetic indicate that a zero was performed with a sample
that contained an anesthetic or another material that absorbs the infrared wavelengths
used for the analysis. The most likely reasons for this are that either a zero gas filter
was not used or the filter that was used is saturated with anesthetic. Replace the filter
with one from a new package and repeat the zero cycle.
For nitrous oxide analysis, the zero gas filter is not effective. In this case a zero sample
must be collected in an area that is free of nitrous oxide. A suitable location is often a
hallway outside the operating suite and well away from the recovery room. If nitrous
oxide analysis continues to give trouble, it is a good idea to establish the analyzer zero
in an area far removed from the operating suite, recovery room and any rooms occupied
by post surgery patients and then to measure the nitrous oxide levels in the hallways
closer to the operating suite in order to identify well ventilated areas that can reliably be
expected to be free of nitrous oxide.