Divesoft HE/O2 Analyzer

Divesoft-He/O2 Analyzer

High-tech analyzer for Nitrox and Trimix breathing gases. After sampling the gas with the included flow reducer, the proportion of helium and oxygen is shown directly and simultaneously on the display.

This Trimix analyzer displays "FOUL AIR" if the percentage of oxygen, nitrogen and helium cannot be determined due to contamination - a significant safety advantage over other analyzers.

Features:

• OLED display
• built-in mixing software
• Modules for the production of gas mixtures using the "constant flow" method, lower and upper warning thresholds for HE and O2 content
• new electronics with lower power consumption
• "Gas purity" option is used to verify the purity of gases. This is primarily intended for use with argon, but can be used for various gases with appropriate adjustments.
• it is also possible to determine the ratio of two gases using different sonic velocities. For example: Helium/nitrogen, helium/argon, hydrogen/nitrogen, hydrogen/argon and many others

Working principle:

A normal electrochemical sensor (R-17D) is used to determine the oxygen fraction. The helium fraction is determined based on the measurement of the speed of sound in the mixed gas.

The sonic velocity depends on the proportion of helium and oxygen as well as on the temperature of the gas.
The influence of atmospheric pressure is minimal and can be ignored under normobaric conditions.
At 0 degrees Celsius, the speed of sound is about 970 meters per second in pure helium, 330 meters per second in air, and 315 meters per second in pure oxygen.
If the temperature is increased by 1 degree, the speed of sound increases by about 0.175%.
The speed of sound in a gas mixture can thus be represented as a non-linear function depending on temperature, oxygen content and helium content.

The speed of sound is determined directly by measuring the time difference of an acoustic signal between two microphones. This measurement is made in both directions and thus equalizes the influence of the flow rate of the gas.

Calibration:
Each analyzer produced is tested in the full spectrum of acceptable oxygen and helium levels.
These tests are performed with air, pure oxygen and pure helium as well as with 12 different calibration mixtures.

The analyzer is supplied with box, simple flow-limiter, and USB cable.