M&C TechGroup SP2006-H280_DIL Operator's manual - Manual (Page 10)

10
Gas sampling and gas conditioning technology 2-1.1.7.2-ME
10 DESCRIPTION
The dilution unit including the critical orifice is mounted directly at the probe body and therefore
heated up with the probe to a stable temperature. The incorporated pre-heater heats up the dilution
gas to the probe temperature. Both steps avoid that sample gas decreases under the dewpoint. Cali-
bration gas enters the probe via an integrated connection.
The probe can be heated up to 180 °C or 280 °C. As an option a heated manual operated 2 way ball
valve is available. It is integrated in the sample gas inlet and shuts off the probe head from the proc-
ess, for example during the change of the filter element. Additional the option „blow back in front of
ball valve‟ via the probe flange is available.
Through an optional high flow rate check valve /BB, which is fixed to the internal probe area, blow
back of the filter housing area and the insitu probe tube will be done. Through the optional high flow
rate check valve /BB/F, which is fixed to the filter housing wall, blow back of the incorporated ceramic
filter will be done incl. the filter area and the insitu probe tube. The optional isolation valve /I shuts off
the sample outlet from the internal filter area.
To optimize the blow back, an incorporated accumulator tank with a volume of two liters is available
as option. To drive this tank an optional air actuated or solenoid valve is offered.
The necessary dilution gas pressure can be adjusted by the precision pressure controller with pres-
sure gauge. A vacuum pressure gauge indicates the function of the dilution system.
The pressure controller and pressure gauges, necessary for the dilution function, have to be ordered
separately. The external control unit -S is equipped with an additional shut-off ball valve and a flow-
meter to adjust the test gas quantity. The set -S1 includes an additional pressure controller for the op-
tion bypass injector
–B or -BR.
The dilution probe realises with injector I dilution rates in a range of 10:1 to 500:1 (with injector II 50:1
– 2000:1). A high dilution rate causes a low sample flow from the process. With underpressure condi-
tions the response time can be minimised using the optional heated bypass injector
–B which is inte-
grated directly upstream the dilution unit. It is available with recirculation into the process -BR as well.
The construction of the probe guarantees an operation which is independent from the process tem-
perature and is easy to maintain as well.