Introduction

The Gasmet FTIR analyser is an ideal tool for toxicity test in fire testing application. It can be used in conjunction with Cone Calorimeter, Smoke Density Chamber for online measurements of combustion gases in fire tests.

Typical application for CEM is H₂O, CO₂, CO, N₂O, NO, NO₂,SO₂, HCl, HF, NH₃, CH₄, C₂H₆, C₃H₈, and C₂H₄. The Gasmet FTIR can be easily to configured for a new set of compounds.

Measured components and calibration ranges can be changed according to application. This technical data sheet describes one example of the system.

The system is used for on- line measurements. It is an ideal tool to use for measuring trace concentrations of gas in combustion studies. All parts of the Gasmet CEMS are be heated up to 180 ºC. It can be used for undiluted gases and the sample gases do not need drying beforehand.

The Gasmet FTIR system consists of Gasmet FTIR CX4000 gas analyser- it is configured to meet ISO 19702 standard, Gasmet PC, Gasmet sampling system. All parts of the system are 19” rack mounted cabinet.

The Gasmet FTIR system includes all power connections and temperature controllers for heated lines and heated sample probe. The operation of the system is fully automatic and controlled by the Calcmet software.

Gasmet PC and Calcmet application software control the systen. The measuring data can be transferred from the PC to the Control room with digital outputs (ModBus) or with analog outputs 4-20 mA.

The Gasmet FTIR system provides different alarm functions such as Function alarm, Service alarm and System alarm. Function and service alarms are associated with the Gasmet FTIR Gas Analyzer and with the Calcmet analysis software. A system alarm comes from Gasmet sampling system and it includes temperature alarms (from sample probe, heated lines, sampling unit), flow alarm and pressure alarm for zero gas. If any of the critical alarms is activated, instrument air starts to flow automatically into the system to prevent condensation.

General parameters

Measuring principle: FTIR (Fourier transform infrared)

Performance: Simultaneous analysis of up to 50gas components

Operating temperature: 20 ± 20 °C, non-condensing,

dust free ambient air.

Storage temperature: -20 - +60 °C

Response time, T₉₀: < 120 s, depending on the gas

flow and measurement time

Gas cell temperature: 50-180 °C

Sample gas: Non-condensing, particle free

Flow rate: ~ 4 l/min

Sample gas pressure: Ambient

Measuring parameters

Zero point calibration: 24 hours, calibration with nitrogen(5.0 or higher N₂ recommended)

Zero point drift: < 2 % of measuring range per zero point calibration interval

Sensitivity drift: None

Linearity deviation: < 2 % of measuring range

Temperature drifts: < 2 % of measuring range per 10K temperature change

Pressure influence: 1 % change of measuring value

for 1 % sample pressure change.

Ambient pressure changes

measured and compensated