Cat. comb. CC: - - - - - - - - - - - -Infrared IR: ––––––––––––––––– by far. As audible or visual alarmswould be disturbing for this kind of application, they are turned off.•No disturbing alarms during special measurement.•Measurement of propane, butane and other gases with positive indication within thedetection range.

Ex-Measurement up to 100 Vol% with thermal conductivity

High concentrations of combustiblegases up to 100 Vol. % can be mea- sured with a special GfG sensor usedin the Polytector. Pressing the „EX“button starts this special measure- ment. The built-in pump is activated and takes gas samples from tubings or tanks. When measuring high volu-me concentrations of gas, the LEL(Lower Explosion Limit) is exceeded

TOX Detection The advantages of GfG’s elec-trochemical sensors for toxicgases:

Even lowest concentrations of various toxic gases might cause poi-soning or health hazards in the long term. The German regulation TRGS 900 has fixed peak concentrations people may be exposed to withoutdanger. The Polytector is capable to monitor 3 toxic gas hazards simulta-neously. State of the art NDIR tech- nology for carbon dioxide and pro-ven electrochemical sensors for avariety of toxic gases complement one another to provide a reliable warning from almost all gas-indu- ced hazards. The electrochemicalsensors can be combined, supple-mented or replaced. •Long lifetime.•Available for many gases, i.e.many combinations possible•Quick response time •Poison resistance pellistor.•Result of the on-going develop-ment of millions of sensors GfG has produced during 40 years.•Long sensor life. •Reliable display behaviour of thesensors.A detector which is calibrated formethane (curve no. 5) indicates all other gases with a more or less important deviation. This deviationof the detection principle „catalyticcombustion“ (marked in yellow) is much lower than that of the „infra- red“ principle. The infrared method triggers a warning (= false alarm)even for lowest concentrations ofmany flammable gases and vapors (e.g. propane, butane, ethane, etc.). Other gases, however, are perceivedmuch too late (e.g. toluene) or notat all (e.g. hydrogen).This is why the catalytic combustion principle is to be preferred over theinfrared method for monitoring offlammable gases and vapors.