13
4 Mounting
VEGAPULS 65 • Foundation Fieldbus
36518-EN-140209
4 Mounting
4.1 General instructions
On instruments with process fitting thread, the hexagon must be tight
-
ened with a suitable screwdriver. Wrench size see chapter "
Dimen-
sions
".
Warning:
The housing must not be used to screw the instrument in! Applying
tightening force can damage internal parts of the housing.
Protect your instrument against moisture penetration through the fol
-
lowing measures:
•
Use the recommended cable (see chapter "
Connecting to power
supply
")
•
Tighten the cable gland
•
Turn the housing in such a way that the cable gland points down
-
ward
•
Loop the connection cable downward in front of the cable gland
This applies particularly to:
•
Outdoor mounting
•
Installations in areas where high humidity is expected (e.g. through
cleaning processes)
•
Installations on cooled or heated vessels
Make sure that all parts of the instrument exposed to the process are
suitable for the existing process conditions.
These are mainly:
•
Active measuring component
•
Process fitting
•
Process seal
Process conditions are particularly:
•
Process pressure
•
Process temperature
•
Chemical properties of the medium
•
Abrasion and mechanical influences
You can find the specifications of the process conditions in chapter
"
Technical data
" as well as on the type label.
4.2 Mounting instructions
The PTFE washer of the antenna encapsulation serves also as
process seal.
To compensate the normal bias voltage loss due to the seal materials,
you have to use also disc springs in addition to the flange screws for
fastening PTFE plated flanges.
We recommend flexible retaining washers (e.g. Schnorr VS or S) or
detent edged rings (e.g. Gross VS
KD).
Screwing in
Protection against mois-
ture
Suitability for the process
conditions
Sealing to the process
