M&C TechGroup SP2000H_DIL_BR Operator's manual - Manual (Page 23)

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Gas sampling and gas conditioning technology 2-1.1.7-ME
W A R N I N G !
In the event of under-temperature (failure of probe heating), the di-
lution gas supply must be interrupted!
14.1 CALIBRATION
Calibration of the downstream analyser system or checking the dilution factor must always take place
under process conditions.
An appropriate calibration gas can be supplied via the cal gas valve.
N O T E !
The gas pressure must be higher than 0.7 bar, as the vacuum valve
mounted on the probe has an opening pressure of 0. 7 bar.
When using the control panel, the respective ball valve for the test
gas supply must be opened and the flow rate set on the flow meter.
The procedure for calibration or checking the dilution ratio is as follows:

Supply test gas of a known concentration to probe.
N O T E !
Calibrate systems analysers directly with zero gas and low concen-
tration sample gas.

Check dilution ratio on downstream analyser and correct pressure on dilution gas supply pressure
regulator.
Test gas supply without bypass injector
To ensure that sufficient test gas is available in the filter space of the probe, the To test gas volume
should be minimum three times the flow through the critical orifice (see injector data sheet).
Test gas supply with bypass injector
The test gas volume must be about 10% higher than the volume flow through the probe produced by
the bypass and the volume flow via the critical orifice (see Fig. 7).
15 DECOMMISSIONING
Prior to decommissioning, i.e. switching off the heating, the probe should be purged with inert gas or
air to prevent the condensation of aggressive components from the process gas.