Operating
Instructions
PHT
28
© SICK AG • Germany • All rights reserved
8013362/1DQY/2021/10/12
Hygienic design typically requires a self-draining set-up such that no product residues
remain at the pressure transmitter upon draining the equipment.
In accordance with the 3-A guidelines, the height of the connecting piece should not be
greater than the connecting piece diameter.
Tank, connecting piece and process connection (on tank) must comply with the guidelines
and applicable standards for hygienic design, e.g. surface roughnesses of parts that come
into contact with media Ra ≤ 0.8 μm.
With the process connection via an instrumentation T-piece, the branch L of the T-piece
must not be longer than the diameter D of the T-piece (L ≤ D).
The mounting position of the instrument, welding socket and instrumentation T-piece
should be designed to be self-draining.
The mounting position must not form a draining point or cause a basin to be formed.
Self-draining mounting position
Not self-draining mounting posi-
tion