Siemens SITRANS P - Manual (Page 6)

SITRANS P measuring instruments for pressure
Transmitters for gage, absolute and differential pressure
Z series for gage and absolute pressure
2/6 Siemens FI 01 · 2009
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Overview
SITRANS P pressure transmitters, Z series for pressure and absolute
pressure (7MF1564-...)
SITRANS P pressure transmitters, Z series (7MF1564-...), mea-
sure the gage and absolute pressure as well as the level of liq-
uids and gases.
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Benefits
• High measuring accuracy
• Sturdy stainless steel housing
• For aggressive and non-aggressive media
• For measuring the pressure of liquids, gases and vapor
• Temperature-compensated measuring cell
• Compact design
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Application
The pressure transmitter of the Z series for gage pressure and
absolute pressure (7MF1564-...) is used above all in the follow-
ing industrial areas:
• Chemical industry
• Pharmaceutical industry
• Food industry
• Mechanical engineering
• Shipbuilding
• Water supply
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Design
The design of the pressure transmitter is dependent on the mea-
suring range.
Measuring range <1 bar (<14.5 psi)
Main components:
• Stainless steel housing with piezo-resistive silicon measuring
cell (with stainless steel diaphragm, temperature-compen-
sated) and electronics module
• Process connection made of stainless steel in diverse designs
(see Selection and Ordering data)
• Electrical connection made using a plug to DIN 43650 with the
cable inlet M16 x 1.5, ½-14 NPT or round plug connector M12.
The pressure transmitters with a nominal range < 1 bar g
(< 14.5 psi g) are optionally available with or without explosion
protection.
Measuring range ≥1 bar (≥14.5 psi)
Main components:
• Stainless steel housing with ceramic measuring cell and elec-
tronics module. The temperature-compensated ceramic mea-
suring cell has a thin-film strain gage which is mounted on a
ceramic diaphragm. The ceramic diaphragm can also be
used for aggressive media.
• Process connection made of stainless steel in diverse designs
(see Selection and Ordering data)
• Electrical connection made using a plug to DIN 43650 with the
cable inlet M16 x 1.5, ½-14 NPT or round plug connector M12.
The pressure transmitters with a nominal range ≥ 1 bar g
( ≥ 14.5 psi g) are optionally available with or without explosion
protection.
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Function
The pressure transmitter measures the gage and absolute pres-
sure as well as the level of liquids and gases.
Mode of operation
SITRANS P pressure transmitters, Z series (7MF1564-...), functional dia-
gram
The mode of operation of the pressure transmitter is dependent
on the measuring range.
Measuring range <1 bar (<14.5 psi)
The silicon measuring cell of the pressure transmitter has a
piezo-resistive bridge to which the operating pressure is trans-
mitted through silicone oil and a stainless steel diaphragm.
The measuring cell output voltage is fed to an amplifier and con-
verted into an output current 4 ... 20 mA. The output current is
linearly proportional to the input pressure
Measuring range ≥1 bar (≥14.5 psi)
The thin-film measuring cell has a thin-film resistance bridge to
which the operating pressure p is transmitted through a ceramic
diaphragm.
The voltage output from the measuring cell is converted by an
amplifier into an output current 4 ... 20 mA or an output voltage
of 0 ... 10 V DC.
The output current and voltage are linearly proportional to the in-
put pressure
p
I
0
, U
B
U
const.
U
I
© Siemens AG 2008