32
6.5 Option “Air speed”
In the air speed mode, the air speed (v) of the gas is meas-
ured in m/s when the gas temperature is 800 °C or less.
Fig. 34: Connection of the S-tube probe
to the PC 410
NOTE!
An S-tube probe (see accessories) is needed for this meas-
urement.
The wanted signal of the Wöhler S-tube probe is better
than that of a normal pitot tube, if the air speed is equal. In
the setup-menu the pitot factor 0,93 must be set once (see
chapter 6.12).
6.5.1 Measuring the air speed
1. Connect the pressure connector of the S-tube to the (+)
overpressure socket of the Lindab PC 410.
2. Connect the static pressure connector of the S-tube to
the (-) underpressure socket of the Lindab PC 410.
3. In calm air, switch on the Lindab PC 410 and wait until
the zeroing procedure of the sensor has finished.
4. When closed, the S-tube can be inserted through the
measurement opening into the gas flow.
5. Fix the S-tube with a cone, open it and direct the sensors
as shown in the figure.
6. If necessary, adapt the S-tube to the cross section of the
gas line with the help of the two knurled screws.
NOTE!
The S-tube must be adjusted before the measurement pro-
cedure starts, since it is required to check and/or adjust the
oppositely running orientation of the measuring tubes after
loosening the knurled screws and adjusting the immersion
depth.
Static pressure
Temperature
Immersion
depth
Flow
Knurled screws
Fig. 35: Measuring the air speed with the
S-tube
7. In the main menu, select "Air speed" and confirm with
OK.
The air speed v is indicated in the upper part of the display.
The temperature, measured by the sensor or the S-tube, and
the ambient pressure Pamb, measured by the integrated
ambient pressure sensor, are indicated in the lower part of the
display.
Also the differential pressure P
D
and the density
r
are indi-
cated.
Fig. 36: Measurement of the air speed
