TESTO AG 400, Инструкция по эксплуатации

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If you have connected a temperature, humidity or absolute pressure probe their values are
accepted directly if you confirm the displayed value via
under SPECIAL - P
ARAMETER
-
Temp., Humidity or Abs. pressure .
Note:
If you work with standard density as set in the factory, the measurement error
during the velocity measurement can be as much as 10% of the measured value. If
the parameters are not correctly adjusted the error can increase considerably.
The density should be checked from time to time or print out the set parameters in addition to
the measured value:
Printing set parameters
You will get the following in the Main menu under PRINT - C
ONFIGURATION
:
- Pitot factor
- Temperature
- Humidity
- Absolute pressure
- Density.
The set parameters are automatically printed every time. The Testo logo is also printed if the
attachable printer (part no. 0554.0570) is connected. Automatic printing of logo and parameter
can be switched on or off via
PRINT - P
RINT LOGO
/P
ARAMETER
.
The following selection appears once the function button is pressed:
1. Timed
2. Multi-point
3. Timed/multi-point.
4. Timed/Graph.
See next page
Mean
Velocity measurement
Mean calculation options
Setting parameters automatically
Density “rho”: setting parameters manually
Density can be entered directly in g/m
3
under SPECIAL - P
ARAMETER
(factory setting:
1293 g/m3).
When confirmed with , this value is used for the calculation, the individual variables are not
taken into consideration.
Alternatively you can enter the variables which influence the air density at the point of
measurement: temperature, relative humidity and absolute pressure.
Once input is confirmed with the density is automatically calculated from this variable. The
result is as follows:
Temperature
Humidity
Density
Absolute altitude
Barometric pressure
Abs. pressure
Differential pressure
Absolute pressure is calculated from
• Altitude (Absolute altitude)
The annual mean is 1013 mbar, the higher the location above sea level, the lower
the pressure
• Barometric pressure
This is independent of the annual average of 1013 mbar. Depending on the weather
this pressure can differ from the annual average by approx. ±20 mbar (See
barometer display on location).
• Differential pressure
This is a reference to over or underpressure in the duct.
Note:
The input of absolute pressure (only in hPa; it is not possible to switch to other
parameters) also affects other parameters which are dependent on pressure. The
pressure is compensated automatically in the following cases: humidity (g/kg,
J/g), CO
2
and in all thermal probes!
Velocity measurement