TEL AFA4000/2, Installation And Operating Manual

Page: 44 / 177

AFA4000/2 Airflow Monitor / p.44
5.1.1 SM7 airflow sensor installation notes
It is very important to position the SM7 airflow sensor in the correct position to give a
long-term stable reading of the face velocity.
Figure 16: Airflow sensor installation diagram
Please read the notes below and if in doubt contact us for further advice.
1. The SM7 sensor must be positioned where it can sense the room pressure of the
laboratory. The back-connection spigot of the sensor is designed to accept a tube
with outside diameter of 25 mm, which should be connected to the inner chamber of
the fume cupboard. This tube and fittings are known
as the ‘vent kit’.
The ideal position for the end of the 25 mm diameter tube, for most fume cupboards,
is 100 mm back from the sash glass and 100 mm higher than the normal sash
opening height through the inner side wall.
2. If possible, mount the sensor on the front of the fume cupboard and use a short
length of tube. Tube lengths of more than 1 m or smaller diameter will restrict the