WPI APOLLO 4000, Инструкция по эксплуатации

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APOLLO 4000
OXYGEN DETECTION
World Precision instruments d-
USING THE APOLLO 4000 TO
DETECT OXYGEN
Initial Set-up
Attach the oxygen sensor to the required sensor input channel on the APollo
4000. From the main setup menu of the software select the correct poise voltage
“oxygen” and appropriate range for the selected channel. the electrode must
now be calibrated.
Calibration and Use of Oxygen Sensors
the ISO-OXY-2 sensor provides accurate, stable and electrically isolated
oxygen measurements. With a probe tip diameter of just 2 mm and low oxygen
consumption, iso-oXY-2 is ideal for making measurements in small sample
volumes. other features include a fast response time and a sturdy stainless steel
probe body.
the iso-oXY-2 in combination with APollo 4000 amperometrically measures
the concentration of oxygen in aqueous solutions and gas mixtures. iso-oXY-2
is not suited for long-term continuous gas measurements, as it needs to
be calibrated on a daily basis. measurements can be displayed either as a
percentage of atmospheric pressure, parts per million (ppm), or as a redox
current in nanoamperes (nA). the iso-oXY-2 houses a platinum working electrode
and a silver counter \ reference electrode inside a stainless steel sleeve. A gas
permeable polymer membrane fits over the end of the sleeve which allows oxygen
to pass while blocking liquids, ions and particulate matter. oxygen diffuses through
the membrane and is reduced at the platinum cathode which is held at -0.7 V
when the instrument is on. this results in an electrical current being generated, the
magnitude of which is determined by the rate of diffusion to the electrode which
is proportional to the partial pressure of oxygen outside the membrane. thus the
current serves as a measure of the partial pressure of oxygen.
iso-oXY-2 comes ready to use. All the user must do is attach the sensor to the
APollo 4000, turn the power on and wait for the current to decay to a stable
value. this usually takes several hours. the current can be monitored directly on
the APollo 4000. once the current stabilizes the user may then calibrate the
instrument.
NOTE: Before
using the
ISO‑OXY‑2
dissolved oxygen
sensor for the
first time, connect
the sensor to
the APOLLO
4000 (power ON)
overnight.