Pyxis 53709, Руководство пользователя

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1 Introduction
The Pyxis ST-773 optical luminescent dissolved oxygen (DO) sensor is based on the principle of ‘fluorescence
quenching’ to determine the dissolved oxygen content in water. It incorporates Pyxis’ advanced technol-
ogy in the field of fluorescence detection and uses dual Blue/Red light detection technology with excitation
and reference light sources, offering a wide detection range and very low detection limit. The sensor also
integrates a temperature sensor for compensation of the measurement of dissolved oxygen based on en-
vironmental conditions. The ST-773 offers an easily replaceable, front loading DO membrane cap that has
been independently developed by Pyxis Lab, with a typical service life of up to two years. This unique
DO membrane cap design incorporates a black microporous PTFE membrane material designed to provide
extreme scratch resistance, extended life span and simple replacement. The flat front-end design of the
ST-773 makes this platform less prone to contamination or fouling and is very easy to clean and brushable.
The sensor body is composed of CPVC and is well suited for aggressive industrial application use. The ST-773
may be utilized in a submersed fixed/floating application or inline with the Pyxis submersion assembly and
inline thread/tee accessory options. The ST-773 comes with a 10-meter bulkhead cable as well as 1.5-meter
flying lead cable each with 7Pin quick adapters. The sensor output offers both 4-20mA and RS-485 Modbus
communication which is Bluetooth enabled when used in conjunction with the MA-WB (7-Pin Bluetooth
Adapter).
The ST-773 series measures the partial pressure of the dissolved oxygen (DO) in water. In most applica-
tions, the source of DO is oxygen in the air. In other application such as in aquaculture, the source of DO is
photosynthesis. The concentration of dissolved oxygen is a derived value from the measured oxygen partial
pressure. The relationship between the DO concentration and the oxygen partial pressure is governed by
the law of thermodynamics. The ST-773 series uses the latest USGS equation to convert the oxygen partial
pressure to DO in units of ppm or mg/L. Through setup using the
uPyxis® Mobile of Desktop App, the ST-773
series sensor can output the measured oxygen partial pressure in other units such as percentage of oxygen
saturation.
ST-773 User Manual service@pyxis-lab.com | +1 (866) 203-8397 2