PRO
2
check
®
Ultrasonic Oxygen Indicator
FREQUENTLY ASKED QUESTIONS (continued)
When I am in the Concentrator Mode and hook the unit up to a U.S.P.
oxygen(> 99.0%) source the LCD does not read 99% (± 2), why?
When the unit is in its default (concentrator) mode the device's software
enables the unit to measure the output of an oxygen concentrator by
compensating for the argon that passes through the sieve beds. In this
mode, it will display a false reading (usually ± 90%) if connected to an
oxygen source other than a concentrator. Pressing and holding the
“
pure
O
2
/calibrate
”
button removes the argon compensation and allows the
device to measure the oxygen purity with ±2% of compressed gaseous or
liquid oxygen.
When I am in the Concentrator Mode and hook the unit up to a U.S.P.
oxygen (> 99.0%) source the LCD the display reads - "Concentrator O
2
91.8" (approx). What's wrong?
Nothing. When in the Concentrator Mode, the electronic components of
the indicator automatically compensates for the argon found in the gas
produced by an oxygen concentrator. As a result the display will read
approximately 90% unless this function is over-ridden by pushing the
“pure O
2
/calibrate”
button.
Whenever I check concentrators with the
PRO
2
check
®
, I consistently get
an O
2
concentration reading of 96.0 on every concentrator. Why?
Concentrators work at their maximum efficiency (96.0%) at lower flow
rates. When the flow rate is increased the output of the concentrator
typically will decrease slightly. If you question whether the device is
functioning properly, stabilize it to room air and then retest with the
concentrator set on the maximum flow rate or beyond. Be sure to allow
the concentrator to stabilize at the higher flow rate before testing. This
may take as long as 10 minutes.
Will the unit lose calibration when I change batteries?
No. The unit holds calibration even when the battery is removed.
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