Pressure reducing and temperature station equipped with an Endress+Hauser Deltabar Proline Prowirl R200 vortex flowmeter and a PMD75B pressure transmitter.

Endress+Hauser Cerabar PMD75: High-Performance Differential Pressure Transmitter

The Endress+Hauser Cerabar PMD75 is a premium differential pressure transmitter designed for critical applications requiring exceptional accuracy, reliability, and advanced functionality. It is part of Endress+Hauser’s Cerabar series, which is renowned for robust pressure and level measurement solutions. The PMD75 is engineered to handle demanding industrial processes in sectors such as oil and gas, chemical processing, power generation, and pharmaceuticals, where precise differential pressure measurement is essential for safety, efficiency, and compliance.

The PMD75 utilizes a silicon-based piezoresistive sensor (often referred to as the "Ceracore" sensor) for high-precision differential pressure measurement. This sensor operates on the principle of piezoresistance, where pressure-induced strain on a silicon crystal diaphragm changes its electrical resistance. The diaphragm is part of a Wheatstone bridge circuit, which converts the mechanical stress into an electrical signal proportional to the applied pressure. This technology ensures minimal drift, excellent long-term stability, and resistance to harsh process conditions. The sensor is isolated from the process media by welded metal diaphragms (e.g., Hastelloy, tantalum, or gold-plated options), making it suitable for corrosive, abrasive, or high-purity applications.

1. High Accuracy and Stability:
   The PMD75 offers accuracy up to ±0.04% of the calibrated span, with exceptional repeatability and long-term stability. Its advanced signal processing algorithms compensate for temperature and static pressure effects, ensuring reliable measurements even in fluctuating process conditions.

2. Safety and Certifications:
   The transmitter is certified for SIL 2 (Safety Integrity Level) according to IEC 61508/61511 standards, making it suitable for safety instrumented systems (SIS). It also carries international certifications for hazardous areas (ATEX, IECEx, FM) and complies with NAMUR recommendations.

3. Advanced Diagnostics and Heartbeat Technology:
   The PMD75 features Endress+Hauser’s Heartbeat Technology, which enables continuous self-monitoring and predictive maintenance. It detects issues such as sensor drift, electronics failures, impulse line blockages, and process anomalies, reducing downtime and ensuring operational safety.

4. Digital Communication and Integration:
   The device supports multiple communication protocols, including 4–20 mA HART, PROFIBUS PA, FOUNDATION Fieldbus, and Modbus RS485, allowing seamless integration into modern control systems. Its intuitive interface with a rotatable LCD display and magnetic pushbuttons simplifies local configuration.

5. Robust Design and Flexibility:
   Constructed with a stainless steel housing and corrosion-resistant materials, the PMD75 operates in extreme temperatures (-40 to 120°C) and handles high static pressures (up to 400 bar). It is available with flush diaphragms for viscous or clogging media and offers options for remote seals for high-temperature applications.

6. Application-Specific Capabilities:
   The transmitter includes built-in functions for flow computation (e.g., square root extraction for orifice plates), level measurement with density compensation, and filter monitoring. Its wide turndown ratio (100:1) ensures versatility across varying process ranges.

• Flow Measurement: Differential pressure across orifice plates, venturi tubes, or flow nozzles.

• Level Measurement: Hydrostatic level detection in closed tanks, including interface level measurement.

• Filter and Pump Monitoring: Pressure drop monitoring across filters, heat exchangers, and pumps.

• Critical Processes: Safety systems, custody transfer, and high-precision control loops.

The Cerabar PMD75 is a top-tier differential pressure transmitter that combines cutting-edge sensor technology, robust construction, and intelligent features to meet the needs of the most demanding industrial applications. Its high accuracy, safety certifications, and advanced diagnostics make it ideal for ensuring process reliability, safety, and efficiency. Whether used in hazardous environments, high-pressure systems, or critical safety loops, the PMD75 delivers unparalleled performance and reduces total cost of ownership through minimal maintenance and long-term stability.