User Manual

40 VEGAPULS 42 and 44 – 4 … 20 mA
Optimum connection to the bypass tube
Strong welding on the tube connection
Tube connection protrudes
Additional connection to the bypass tube in one plane
Mounting and installation
With a liquid quantity of 300 … 800 mm in the
blind lower end of the tube, the portion of the
signal that penetrates the liquid and reflects
from the tube bottom is sufficiently damped -
the sensor can then easily distinguish it from
the echo of the liquid surface. If not enough
liquid remains, a deflection plate located at
the bottom of a vertical pipe can provide the
same function. It deflects the signal reflected
from the tube end sideways into the standard
tube opening.
Connections to the bypass tube
The connections to the bypass tubes must
be fashioned in such a way that only minimal
reflections are caused by the walls of the
connecting tubes. This is especially important
for the breather connection in the upper part
of the tube. Observe the following points:
• Use small openings for the connection.
• The diameter of the connecting tubes
should not exceed 1/3 of the bypass diam-
eter.
• The tube connections must not protrude
into the bypass.
• Big weld joints in the tubes should be
avoided.
• Additional connections to the bypass tube
must lie in the same plane as the breather
openings (superimposed or displaced by
180°).