Siemens SITRANS P - Manual (Page 21)

SITRANS P measuring instruments for pressure
Transmitters for food, pharmaceuticals and biotechnology
SITRANS P Compact
for gage and absolute pressure
2/21 Siemens FI 01 · 2009
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Overview
The SITRANS P Compact pressure transmitter is designed for
the special requirements of the food, pharmaceutical and bio-
technology industries.
The use of high-grade materials guarantees compliance with hy-
giene regulations.
Particular value has been placed on a high surface quality. It is
therefore possible, for example, to guarantee roughness values
down to R
a
= 0.4 μm (1.57 ⋅ 10 -5 inch) in the wetted area
(welded seam area R
a
< 0.8
μm (3.15 ⋅ 10 -5
inch)). The system
can be electropolished in addition.
A further important feature is the hygiene-based design of the
process connection by means of various aseptic connections.
The completely welded stainless steel housing can be designed
up to degree of protection IP67.
Using appropriate thermal decouplers, the SITRANS P Compact
pressure transmitter can be used for process temperatures up to
200 °C (392 °F).
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Benefits
• Measuring ranges from 0 to 160 mbar (0 to 2.32 psi) to 0 to
40 bar (0 to 580 psi)
• Linearity error including hysteresis < +0.2% of full-scale value
• Piezo-resistive measurement system, vacuum-proof and over-
load-proof
• Hygiene-based design according to EHEDG, FDA and GMP
recommendations
• Material and surface quality according to hygiene require-
ments
• Wetted parts made of stainless steel; completely welded
• Signal output 4 to 20 mA (0 to 20 mA as option)
• Stainless steel housing with degree of protection IP65 (IP67 as
option)
• Process temperature up to 200 °C (392 °F)
• Explosion protection II 2G EEx [ib] IIC T6 to ATEX
• Easy and safe to clean
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Application
The SITRANS P Compact pressure transmitter is designed for
the special requirements of the food, pharmaceutical and bio-
technology industries.
The use of high-grade materials guarantees compliance with hy-
giene regulations.
The SITRANS P Compact pressure transmitter is available in
many versions. Exact adaptation of the pressure transmitter to
conditions at the place of use is thus possible
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Design
The electronics is potted to protect it against moisture, corrosive
atmospheres and vibration.
Notes on operating the pressure transmitter
Compensation of internal atmospheric pressure
Compensation of the internal atmospheric pressure of the
SITRANS P Compact pressure transmitters is performed as fol-
lows:
• in the plug versions by means of the screwed gland (IP65)
• in the field housings by means of an integral sintered filter
(IP65) or a vented cable (IP67)
• in versions with cable outlet by means of a vented cable (IP67)
In the absolute pressure range there is no need for compensa-
tion with respect to atmospheric pressure.
Note: These degrees of protection are only achieved under the
following conditions:
• if the pressure transmitter is installed correctly
• if the screwed glands are securely tightened
• if the cable diameters agree with the nominal diameters of the
gaskets in the housing
Note: The integral EMC measures are only effective if the earth
connection is made correctly.
CE marking
The CE marking of the pressure transmitter certifies compliance
with the guidelines of the European Council (9/336/EC), the EMC
law (13.11.1992), as well as the applicable generic standards.
Interference-free operation in systems and plants is achieved
only if the specifications for shielding, earthing, cable routing
and electrical isolation are observed during installation and as-
sembly.
Hazardous areas
Note: Electrical equipment in hazardous areas must only be in-
stalled and operated by trained personnel.
Modifications to units and connections result in cancellation of
the explosion protection and guarantee.
With intrinsically-safe circuits, make sure that equipotential
bonding exists throughout the complete cabling inside and out-
side of the hazardous area. The limits specified in the ATEX ap-
proval must be observed.
© Siemens AG 2008