The Signal Group’s 821S gas divider enables the users of gas analysers to test the linearity of their instruments – simply, quickly and accurately.

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Extremely reliable repeatability performance of +/- 0.5% of point

Remote control allowing automated instrument linearity auditing and calibration

Simply connect the gases and rotate the selector switch

No change in flow with change in dilution

Easy to use...

The Signal Group Gas divider has been designed for testing the linearity of any gas analyser.

The 821S has ten identical capillaries and a precision balance regulator. The span gas can be selected to flow through a number of those capillaries with the diluent flowing through the remainder, to produce a ratio.

Many types of gas analyser are inherently non-linear due to the physical nature of the analysing technique. Photometric analysers (NDIR, NDUV, FTIR / spectrophotometers) need to be linearised before they leave the factory and then at regular intervals during service. Other more linear analysers will also need to be checked for linearity periodically whilst in service. This should be part of the QA/ QC regime.

Rapid service assures environmental accreditation

In April 2022, Leeds based Alkali Environmental was awarded UKAS and MCERTS accreditation for its emissions testing services. However, just three weeks before the MCERTS audit, a vital piece of the company’s in-house instrumentation, the Signal Group 821S Gas Divider, required urgent service and repair, so the company faced the very real prospect of having to defer the audit.

Read how our service team repaired and returned their equipment within 22 hours! More than enough time for the audit to go ahead.

Giving you the tools to validate your gas analysis.