Cerabar M PMP71B

Summary

Product Identification

• Product Name: Cerabar M PMP71B
• Type: Digital pressure transmitter with metallic process membrane
• Document Revision: EN/09.25-00

Applications

• Process pressure and level measurement in liquids or gases.
• Pressure Measuring Ranges: Up to 700 bar (10,500 psi)
• Process Temperatures: Up to 400 °C (752 °F) with diaphragm seal
• Accuracy: Up to ±0.025%

Key Advantages

• Easy local or remote operation.
• Enables condition-based maintenance.
• Smart safety features.
• Intuitive firmware with wizard navigation for commissioning and verification.
• Bluetooth connectivity for safe, remote operation.
• Large, backlit display for excellent readability.
• Heartbeat Technology for on-demand verification and monitoring.

Measuring Principle

The device utilizes a metallic membrane. Pressure deflects this membrane, and a fill fluid transfers it to a Wheatstone bridge (semiconductor technology). The resulting pressure-dependent change in output voltage is measured and evaluated.

For devices with diaphragm seals, pressure acts on the diaphragm seal's membrane, transferring to an internal membrane via a fill fluid. This internal membrane deflects, and a resistance bridge evaluates the pressure-dependent change.

Measuring System

Available in two main versions:

• Standard device (without diaphragm seal)
• Device with diaphragm seal (compact, with temperature isolator, or with capillary)

Diaphragm seal systems are used to separate the process from the device, particularly in cases of:

• Extreme process temperatures
• Strong vibrations
• Aggressive or corrosive media
• Media that crystallize or contain solids
• Heterogeneous and fibrous process media
• Difficult-to-access mounting locations

Communication and Data Processing

• Protocols:
  • 4 to 20 mA with HART communication protocol
  • Bluetooth (optional)
  • PROFINET with Ethernet-APL (10BASE-T1L)
• IT Security: Features include hardware write protection, access codes, web server access, and user-specific password protection.

Input

• Measured Variable: Absolute pressure, Gauge pressure.
• Measuring Range:
  • Absolute Pressure: Up to 700 barabs (10,500 psiabs) with various measuring cells. Smallest calibratable spans range from 0.005 bar to 7.0 bar.
  • Gauge Pressure: Up to 700 bar (10,500 psi) with various measuring cells. Smallest calibratable spans range from 0.005 bar to 7.0 bar.
  • Overpressure Limit (OPL): Varies by measuring cell, up to 1050 bar (15,750 psi) for the 700 bar cell (standard device).
  • Maximum Working Pressure (MWP): Varies by measuring cell, up to 700 bar (10,500 psi) for the 700 bar cell.

Output

• Output Signal:
  • 4 to 20 mA with HART (selectable modes: 4.0 to 20.5 mA, NAMUR NE 43, US mode).
  • PROFINET with Ethernet-APL (10BASE-T1L, 10 Mbit/s).
• Signal on Alarm: Configurable for 4-20 mA HART (Max alarm, Min. alarm) and PROFINET diagnostics.
• Damping: Continuously adjustable from 0 to 999 seconds (factory setting: 1 s).
• Linearization: User-defined linearization tables (up to 32 value pairs) can be entered.

Performance Characteristics

• Response Time:
  • HART (acyclic): min. 330 ms, typically 590 ms
  • HART (cyclic/burst): min. 160 ms, typically 350 ms
  • PROFINET with Ethernet-APL: min. 32 ms
• Reference Operating Conditions: Per IEC 62828-2, with specified ambient temperature, humidity, and pressure.
• Total Performance: Calculated as ± √((E1)² + (E2)²), where E1 is reference accuracy and E2 is ambient temperature effect.
• Reference Accuracy: Varies by measuring cell and turn down ratio (TD). For platinum measuring cells, accuracy can be as high as ±0.025%.
• Temperature Effect (E2M): Varies by measuring cell and TD.
• Electronics Error (E2E): 0.05% for 4 to 20 mA; 0% for digital outputs.
• Resolution (Current Output): < 1 μA.
• Long-Term Stability: Ranges from ±0.05% for 1 year (all other measuring cells) to ±0.14% for 15 years (400 mbar to 4 bar cells).

Installation

• Mounting: Orientation can affect zero point. Housing and display can be adjusted. Mounting brackets are available. Flushing rings recommended for flanges to prevent buildup.
• Installation with Diaphragm Seals: Systems are pre-filled and sealed. Capillary fill liquid column hydrostatic pressure must be considered for zero point shift. Capillaries require a minimum bending radius of 100 mm and must be mounted vibration-free.
• Vacuum Applications: Ceramic membrane transmitters are recommended. If using a diaphragm seal, specific mounting orientations are recommended to prevent vacuum loading.
• Warm-up Time: ≤ 5 s (according to IEC62828-4).

Mechanical Construction

• Materials in contact with process: See official PDF for specific material options.
• Weight: See official PDF for specific values.

Electrical Connection

• Supply Voltage:
  • Analog/HART (Ex d, Ex e, non-Ex): 10.5 to 35 VDC
  • Analog/HART (Ex i): 10.5 to 30 VDC
  • PROFINET over Ethernet-APL: 9.6 to 15 VDC (540 mW)
• Terminals: Accommodate wire sizes from 0.5 to 2.5 mm² (20 to 14 AWG) for supply voltage and internal ground, and 0.5 to 4 mm² (20 to 12 AWG) for external ground.
• Cable Entries: Various types depend on device version. Cables should be routed downwards.
• Overvoltage Protection: Optional overvoltage protection available; tested according to relevant IEC standards.

Certificates and Approvals

Includes CE mark, RCM-Tick, Ex approvals, EAC conformity, and optional Drinking water approval.

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Disclaimer: This extraction may miss figures, footnotes, or revisions. Contractual data must match the OEM PDF revision used on the project.

Official datasheet (PDF)

Lenntech datasheet mirror