M&C TechGroup DIL-1_(H) Operator's manual - Manual (Page 24)

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Gas sampling and gas conditioning technology 2-1.1.7.6-ME
14.1 CALIBRATION
A calibration of the downstream analyser system or checking the dilution factor must always be ef-
fected under operation conditions.
Above the test gas valve, an appropriate test gas can be feeded.
W A R N I N G !
The gas pressure must be above 0,7 bar, because the pressure
control valve installed 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 be set on the flow-
meter.
The procedure for calibration or checking the dilution ratio is as follows:

Supply test gas of a concentration you know.

Check the dilution ratio on the downstream analyser and, if necessary, correct the pressure on the
pressure regulator of the dilution gas.
Test gas feeding without bypass injector
In order to assure that sufficient test gas is available, the test gas quantity should be at least threefold
of the flow quantity passing through the critical orifice (see injector data sheet).
Test gas feeding with bypass injector
The test gas quantity must be approximately 10% above the quantity of the volume flow passing
though the bypass (see figure 12) and the critical orifice (see figure 11).
15 CLOSING DOWN
Prior to closing down, the heated dilution unit should be purged with inert gas or air to prevent the
condensation of agressive components from the process gas.