VEGA VEGASWING 83 fail safe and signal conditioning instrument VEGATOR 526 Ex - Manual (Page 14)

14 VEGASWING 81 W5 Ex.C, 83 W5 Ex.C fail safe
Pressure
In case of overpressure or gauge pressure in
the vessel, the mounting boss must be sealed
on the thread. Cover the thread with Teflon
tape, hemp etc. or use a seal ring.
Vibrations
Extreme vibrations and shocks e.g. by stirrers
and turbulences in the vessel can energize
the extension tube of VEGASWING 83 to
resonance frequencies. This causes an
increased wear on the upper weld joint.
Therefore provide a suitable support or fixing
directly above the tuning fork to fasten the
extension tube (see fig. 2.3).
This is mainly valid for applications in Ex-area
zone 0 or acc. to VbF. Note that the tube is not
bent by this measure.
Humidity
Turn the cable entry of horizontally mounted
instruments to the bottom to avoid humidity
ingress. The plastic housing is therefore
rotational by approx. 330
°
. For vertically
mounted instruments loop the connection line
to the instrument housing to the bottom so that
rain and condensation water can drain off.
This is mainly valid for mounting outside, in
humid areas (e.g. by cleaning processes) or
on cooled or heated vessels (see fig. 2.4).
Mounting
Stirrers
Due to stirrers etc. the level switch can be
subjected to strong lateral forces. For this
reason the extension tube of VEGASWING
83␣ W5␣ Ex.C should not be too long, better
check if it is possible to mount a level switch
VEGASWING 81␣ W5␣ Ex.C laterally in horizon-
tal position.
Lockings
For VEGASWING 83…␣ G and 83…␣ N a locking
is available for height adjustment. The switch
point can be adjusted after mounting and
modified afterwards.
Adjust the switch point of the tuning fork to the
requested height. By tightening the pressure
screw you fix the tube to this position.
For pressure applications you have to secure
the pressure screw with the fixing screw.
VEGASWING 83…␣ G and 83…␣ N can be used
in vessels with up to 4␣ bar pressure. Therefore
use the locking (G␣ 1
1 /
2
␣ A, 1 /
2
“␣ NPT) up to 4␣ bar
(ARV2EX0.C…). Note the operating instruction
of the locking.
Fig. 2.3
Fig. 2.4