DURAG D-R 290, Operating Manual

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7 | Checking / setting parameters with D‑ESI 100
148 D-R 290
Measurement tube for a dust-free measurement path
For the adjustments described in the previous sections a "dust-free measurement
path", "dust free area", or a "measurement tube" are required. All three terms repre­
sent a defined dust free measuring path. A corresponding tube can be supplied by
DURAG, but you can also manufacture your own. If you do this, note that a diaphragm
should be fitted within the internally blackened tube every 500 mm (see drawing). Dia­
phragms are available as accessories.
To simplify alignment of the measurement configuration, it is advisable to order two
optional additional purge air flanges and to mount them on the flanges of the
measurement tube. For measurement only the reflector and measuring head need
then be installed there. This means the measurement configuration requires optical
alignment only the first time it is installed. For every further measurement the devices
are then need only be mounted on to the purging air flanges with the quick-release
clamps.
max. 250 mm
Measurement tube for a smoke-free measurement path
500 mm distance from diaphragm to diaphragm
Purge air flange Purge air flange
Diaphragm
optional optional
Measuring path
Diaphragm
Hole circle Ø 100 mm external Ø 89 mm internal Ø 83 mm
Fig. 7.22: Measurement tube for a smoke-free measurement path
7.7.9
Fig. 7.21: Diaphragm