Instructions For Using Positioners Which Are Exposed To Strong Accelerations Or Vibrations - Siemens SIPART PS2 6DR50xx Manual

Preparing for Operation
Assembly of the screw-type gland with plastic hose
3.3.2 Instructions for using positioners which are exposed to strong
accelerations or vibrations
46
Unscrew the sinter bronze silencer from the exhaust air opening on
S
the underside of the housing.
Screw the screw-type gland mentioned above into the exhaust air
S
opening.
Mount the above mentioned plastic hose on the screw-type gland
S
and check the good fit.
Fix the plastic hose with a cable strap to the fitting so that the open-
S
ing faces downwards.
Make sure that the hose has no kinks and the exhaust air can flow
S
out unhindered.
NOTICE
for explosion-proof versions:
Only adjust the outer friction clutch (8, Fig. 2-12, page 31). The internal
friction clutch (8, Fig. 2-11, page 28) is fixed and, for the explosion-
proof version, must not be adjusted.
The electro-pneumatic positioner SIPART PS2 has a friction clutch and
switchable gearing and can thus be used universally for part-turn and
linear actuators. This means that, for part-turn actuators you don't have
to worry about the zero point and for linear actuators, you don't have to
worry about symmetrical mounting, as you can adjust the working
range after installation, with the help of the friction clutch.
The switchable gearing allows you to also adjust the positioner for
small or large lifts.
Occasionally it can happen, that in the rough environment of process
systems (e.g. due to incorrectly fitted valves or if "steam pulses" occur)
that the shaft to monitor the position of the SIPART PS2 positioner is
exposed to extreme acceleration, which far exceeds its specified load
limits, and which could result in an unwanted shift in the friction clutch
or in the gears in the position monitoring jumping briefly out.
For cases like this, as standard, the SIPART PS2 positioner is fitted
with a locking device for the friction clutch and you can also lock the
setting of the transmission ratio selector. This means that an unwanted
change to the position monitoring due to the above mentioned effects
can be reliably prevented.
Both of these locking options are labeled via additional tags inside the
device (see Figure 3-6, page 47). Note that these locks are only re-
quired if extreme acceleration or strong vibration might be present
within your process.
SIPART PS2 Manual
A5E00074631--06