MBW 473-RP2, Operation And Maintenance Manual

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MBW 473 Manual English V5.0 21
This picture shows a possible set up
for the SH3 measuring head. A stain-
less steel tube is connected to the
gas inlet. At the gas outlet there is a
mechanical flow meter installed to
regulate and measure the gas flow
rate. We recommend 0.5 - 1 lpm for
frost point measurements. A flow
rate of 0.5 lpm is suitable for dew
point measurements.
Please note that connecting tubes as
well as flow meter are not included
with the instrument.
SH3 Fan
One of the differences of the SH3 measuring head to the SH2 measuring head is that it does not have
a sample gas flow fan. The purpose of the fan installed on the SH3 is to cool the measuring head
base. The fan dissipates the heat generated by the Peltier during operation. This is especially im-
portant when measuring low frost points. To prevent the measuring head from overheating the fan
runs continuously during operation and cannot be switched off. The
Fan button on the display refers to
the gas flow fan of the SH2. Therefore, when you have a SH3 measuring head installed and you press
the
Fan button, a message will appear saying you that there is no fan installed.