ACIN Betz 2500/250, Руководство пользователя

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12
6.1 before use
reading
•
Adjust the position of the end of the light guide (11) to obtain optimal quality and light intensity of the
projected image on the screen.
correct fluid level
•
In a zero pressure situation, set the screen in its middle position by means of the zero adjuster (1).
•
The fluid level is correct when the projected zero line from the glass scale coïncides with the zero line on
the adjustable projection screen.
•
If there is a substantial difference that can not be adjusted by means of the zero adjuster (1), refer to 5.3
to correct the fluid level.
leakage
•
Check if the cones of the pressure connections (4) are clean and free of oil and press them firmly in their
fittings.
•
Connect the (+) and (-) connections (4) to a pressure difference source by means of two flexible tubes
with an inner diameter of ø4 .. ø8 mm.
•
Increase the pressure slowly to the full scale value. Close the (+) pressure tube and check if the micro-
manometer retains the reading for a while. If not, check all connections.
•
Then lower the pressure slowly to zero; if the zero-reading returns correctly the instrument is ready for
use.
•
This procedure also provides the necessary moistening of the riser tube inner wall.
6.2 during use
Take care that the applied pressure does not exceed the maximum measuring capacity during measure-
ments. If this happens, the fluid level should be checked again. In addition, make sure no measuring fluid
has entered the minus (-) side connection. Unscrew the top cap of the riser tube and make sure no drops of
fluid are present. If short bursts of high pressure are possible it is advisable to use some sort of damping in
the pressure supply tube, for example by means of a restriction or an adjustable clip.
As light that enters the instrument via the light guide does not warm up the instrument, it is possible to leave
the cold light source switched on for a longer period of time. However, do not place the cold light source too
close to the instrument, to prevent warming up through radiation. In normal circumstances, choose setting
1 for maximum bulb life (approx. 10 000 hours).
6.3 temperature correction
The micromanometer is calibrated at 20°C. If the micromanometer is used outside a climate chamber, make
sure that the ambient temperature remains constant during measurements and use a correction factor:
6. operation
6.4 examples of read-out
Betz type 2500
The glass scale is subdivided in 10 Pa,
the projection screen nonius in 1 Pa.
Example shows the value of 1579.3
Pa
Betz type 5000
The glass scale is subdivided in 10 Pa,
with figures every 20 Pa. The projection
screen nonius is subdivided in 2 Pa.
Example shows the value of 3514.8
Pa
english
temperature (°C) correction factor
15 1.00090
16 1.00075
17 1.00050
18 1.00035
temperature (°C) correction factor
19 1.00015
20 1.00000
21 0.99975
22 0.99950
temperature (°C) correction factor
23 0.99930
24 0.99910
25 0.99880