Lindab PC 410 - Theoretical Background

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• Press the left key to bring up the menu again.
• Press the right key to zero the pressure sensor.
NOTE!
The pressure sensor must be zeroed, if the meter does not
indicate V=0 after the tubes have been removed.
6.5.2 Theoretical background
The PC 410 will calculate the air speed automatically according with the following formula:
v = S
p
2 ∆p
Formula 1
The air density r is determined as follows:
ρ =1,29 ·
kg
m³
273 °C .P
akt [hPa]
(ϑakt [°C]ϕ+273 °C) · 1013 hPa
Formula 2
Explanation: v: air velocity in m/s
r: air density, ca. 1.29 kg/m³ (depends on temperature and air pressure)
∆p: Differential pressure in Pa, measured with the S-tube
P
akt
: ambient air pressure, measured by the PC 410
S: Pitot factor 0,93 for S-tube probe
J
akt
: Measured Temperature
NOTE!
If the airflow reading is not stable or if the resolution is not
high enough, go to the Setup-menu and select Attenuation
> fine (see chapter 6.12)