© Siemens AG 2011
Pressure, absolute pressure, differential pressure, flow and hydrostatic level measurement
SITRANS P is a family of pressure measuring instruments. The SITRANS P DS III and P300 digital transmitters are suitable as universal transmitters for measuring gauge pressure, absolute pressure, and differential pressure, and also for flow and hyd- rostatic level measurement.
They have a series of integrated diagnostic and simulation functions that allow the user to assess the specific state of the device or of the whole measurement point during commissio- ning, servicing and maintenance operations.
The preventive maintenance is supported by functions such as:
•Operating hours counter for measuring cell and electronics,
•Event counter for upper and lower limit violation,
•Min/max pointer for pressure, sensor temperature and electronics temperature, and
•Two freely parameterizable timers that can set off a war- ning or an alarm on reaching a preset threshold.
As part of the corrective maintenance the device diagnostics effectively support the clearance of faults. For this, the fol- lowing are cyclically monitored:
•Memory integrity of RAM, ROM and EEPROM by means of checksum method
•Correct program sequence in microcontroller due to targe- ted approach to checkpoints (watchdog)
•Sensors for breakage and function of the linearization cal- culation
In addition, simulation functions are available for checking the configuration of the transmitter and of the connected control system input. These also contribute to fast and definitive trou- bleshooting and thus to greater efficiency in the maintenance operations.
From the combination of the stated functions, measures can be derived that contribute to the prognostic maintenance and thus increase plant availability even further and help to raise productivity.
SITRANS P300, digital display
Flow measurement
For flow measurement, Siemens offers various contactless measurement procedures:
•SITRANS F M MAGFLO
•SITRANS F C MASSFLO Coriolis mass flow meters
The devices are flexible in their application and can be positi- oned at any point in the installation.
MAGFLO and MASSFLO flow meters provide excellent, correct and predictable information about the HART or PROFIBUS Pro- fil interfaces. The latest MASSFLO version "SIMATIC SIFLOW FC070 Coriolis transmitter" can be directly integrated into the SIMATIC system via the backplane of the SIMATIC module. SIMATIC SIFLOW FC070 has a SIMATIC
MAGFLO flow meters are used for applications with conducti- ve liquids and MASSFLO flow meters, for example, for non- conductive liquids, high precision requirements or in proces- ses in which the process parameters are subject to severe fluc- tuations.
MAGFLO flow meters are not sensitive to fluctuations in tem- perature, pressure, viscosity or electrical conductivity (min.
5 µS/cm guaranteed).
The device is equipped with a host of diagnostic functions that are displayed in plain text and stored in a logbook. In this way, sporadically occurring faults can also be located. These faults are automatically sent to the system in accordance with the standards of the diagnosed requirements of NAMUR NE 107.
The measuring transducer, including outputs, is monitored. The pickups are continuously checked and empty pipe detec- tion is performed. In addition, MAGFLO flow meters offer the option of checking the entire measurement system with an external verifier.
SITRANS P DS III