Analyzer HE/O2 FAQ

How long is the oxygen sensor's service life?

An electrochemical sensor is used for measuring the oxygen content. When measuring (and even storing the sensor in air), a chemical reaction occurs in the sensor. The sensor's service life is is determined by the depletion of the reagent. The expected service life of the sensor is three years when stored in air at normal temperature with 50% humidity. It is necessary to replace the sensor upon expiration of its service life.

How long is the helium sensor's service life?

The helium content is determined using a physical method which in causes no wear and tear in the sensor. Therefore, the sensor's service life is, in principle, unlimited.

Is it possible to measure other gases with the analyzer?

Firmware versions prior to 2.19: No. The analyzer is intended only for mixtures containing air (more precisely, nitrogen with characteristic presence of atmospheric argon), oxygen and helium. The presense of another gas (e.g., a larger amount of CO2) in the mixture causes unreliable results. Under certain conditions, the analyzer can be modified for mixtures containing other gases. More information about the possibilities of modification and calibration can be obtained from the manufacturer.

Firware versions 2.19 and later have special "Gas purity" mode, which can measure any binary gas mixture, if sound velicities in each component are different enough. You have to define physical parameters of each component (both specific heats Cp and Cv and molar mass). If fact, a component can be a mixture, but each must contain different gases. Default setting measures Ar and air.

Can the analyzer identify trace amounts of helium?

The analyzer measures with differentiation on the order of tenths of a percent. Thus, helium in a concentration smaller than the analyzer's differentiation cannot be identified.

Why does the analyzer show that there is -0.3% helium in air?

Of course, the correct value would be zero. However, measuring is hampered by unavoidable discrepancies on the order of tenths of a percent. As such discrepancies can be positive or negative, it therefore can happen that the analyzer shows -0.3 % or 0.3 % helium in air, just as 99.7 % or 100.3 % may be displayed when measuring pure helium.

Similar situation is with measuring of oxygen. Possible error is up to 1 % (depending on manufacturer of O2 cell).

Values are displayed as calculated, there are no hidden altering of measured data to make values look better.

I upgraded the firmware and He sensor stopped working

In older firmware revisions the measuring click was hard coded to 30us. Starting with revision 2.18, the click duration is adjustable in range 10-250us. If the stored value was less than 30, the measuring click is not strong enough to be detected. Use this guide to repair.

I get "Ambient pressure sensor not present" error

Analyzers version 4 are equipped with ambient pressure sensor, which helps keep proper oxygen sensor calibration. I can happen that for some reason it is disabled and then you get the error message described above. Use this guide to repair.

Is it possible to put a rechargeable 9V battery in the analyzer?

Yes, it is, but it will not be recharged, 9V supply is for primary cell only. Starting with version 4, the analyzer is prepared to use LiIon rechargeable cell, but it has to be installed inside the device. This built-in battery can be recharged using external power supply or USB cable. The battery kit is not available yet at this moment, please check our News section on main page.

I get Error 7 "Accumulator is empty", but I have no accumulator installed.

This error can appear when the 9V battery is very discharged, so the analyzer assumes it is supplied from accu. Please replace the 9V battery.

What are differences between SOLO and He/O2 analyzers?

Check here.