The EMERSON 8750-CA-NS is a high-performance, ultra-low flow, integral-orifice differential pressure (DP) flow transmitter, part of Emerson’s flagship Rosemount™ 8750 Series of vortex and magnetic flowmeters. This specialized instrument is engineered for the precise measurement of extremely low flow rates of clean, dry gases, steam, or liquids in critical industrial processes. Unlike standard flowmeters with remote orifice plates, the EMERSON 8750-CA-NS features a compact, integrated design where the primary element (a precisely machined integral orifice) and the advanced multi-variable DP transmitter are housed within a single, robust unit. This design eliminates the need for separate impulse lines, manifolds, and extensive piping, dramatically reducing potential leak points, installation costs, and maintenance requirements while significantly improving measurement integrity and system responsiveness.
The core operational principle involves the generation of a differential pressure as the fluid passes through the integral orifice. The integrated sensor and microprocessor of the EMERSON 8750-CA-NS then accurately measure this DP, along with the process temperature and static pressure. Using these three variables, the transmitter’s powerful flow computer calculates and outputs a precise mass or volumetric flow rate, corrected to standard conditions. Its value lies in its exceptional accuracy, compact footprint, and ability to handle low flow applications that challenge other technologies. In industries like semiconductor manufacturing, pharmaceutical production, and fuel cell research, where precision and reliability in measuring small gas flows are paramount, the EMERSON 8750-CA-NS provides a robust, all-in-one solution that ensures process consistency, improves yield, and enables tight control over material consumption.
Technical Specifications
Parameter Name
Parameter Value
Product Model
EMERSON 8750-CA-NS
Manufacturer
Emerson Automation Solutions (Rosemount™ brand)
Product Type
Integral Orifice, Ultra-Low Flow Differential Pressure Transmitter
Primary Element
Integral, machined orifice with specific Beta (d/D) ratio for low flow
Flow Measurement
Mass or volumetric flow for clean, dry gases, steam, and liquids
Process Connection
Typically ½” NPT or ¼” NPT male or female (specific to model suffix)
Accuracy
Up to ±0.5% of rate for gas and liquid mass flow (with multi-variable compensation)
Rangedability
High turndown (e.g., 10:1 or greater), suitable for low flow rates
Output Signals
4-20 mA HART®, Foundation™ Fieldbus, or PROFIBUS® PA (model dependent)
Multi-Variable Output
Simultaneous outputs for mass flow, volumetric flow, density, and process temperature
Process Temperature Range
Standard: -40 to 150°C (-40 to 302°F); Extended ranges available
Process Pressure Rating
Up to 1450 psig (100 bar) standard
Electronics Housing
Cast aluminum with polyurethane coating, NEMA 4X (IP66/67)
Sensor Technology
Advanced silicon piezoresistive sensor for DP, RTD for temperature
Key Features and Advantages
The EMERSON 8750-CA-NS stands out for its precision engineering and integrated simplicity in low-flow applications. Its most significant advantage is the elimination of impulse lines. By combining the orifice and transmitter, it removes the common problems associated with traditional DP installations: leaks, blockages, and the time-consuming process of filling and bleeding impulse lines. This not only reduces installation time and material costs by over 50% but also enhances long-term reliability and safety, particularly in hazardous areas or with expensive/toxic process media.
8724-CA-PS
The compact, single-body design also saves valuable space in dense pipe racks or skids.
Ultra-low flow capability and high accuracy are at its core. The integral orifice is specifically designed and calibrated for low Reynolds number flows, enabling precise measurement where other flowmeter types may fail to maintain accuracy or stable signal. The device incorporates advanced multi-variable sensing, measuring differential pressure, static pressure, and process temperature simultaneously. This allows the EMERSON 8750-CA-NS to perform real-time compensation for changes in fluid density and viscosity, directly calculating and outputting highly accurate mass flow—a critical parameter for inventory control and batching processes—without requiring external calculations from the control system.
Advanced diagnostics and user-friendly configuration further define its value. Equipped with Emerson’s powerful AMS™ Suite device management software compatibility via HART or digital bus protocols, the transmitter provides continuous health monitoring, including diagnostics for plugged impulse ports or sensor integrity. The local operator interface (LOI) or handheld communicator allows for easy configuration, ranging, and troubleshooting without opening the electronics housing. Its robust NEMA 4X/IP66 enclosure ensures reliable performance in harsh environments. For applications demanding precise control of low flows, such as carrier gas in analyzers, purge gas flows, or chemical additive injection, the EMERSON 8750-CA-NS delivers unmatched reliability, accuracy, and ease of use.
Application Areas
The EMERSON 8750-CA-NS excels in applications requiring precise, reliable measurement of very low flow rates, particularly of gases, in industries where process efficiency and control are critical. In semiconductor and electronics manufacturing, it is indispensable for monitoring and controlling ultra-pure carrier and process gases (such as nitrogen, argon, or helium) in chemical vapor deposition (CVD), diffusion furnaces, and etching tools. Accurate measurement of these expensive gases is vital for process repeatability, wafer yield, and cost management. Similarly, in pharmaceutical and biotechnology production, it is used to measure low flows of clean-in-place (CIP) gases, purge gases for sterile processes, and precise additive flows in bioreactors.
In analytical systems and laboratory pilot plants, the EMERSON 8750-CA-NS is the ideal choice for metering sample streams, calibration gases, and reactant feeds to gas chromatographs, mass spectrometers, and other analyzers. Its compact size and high accuracy make it perfect for skid-mounted analyzer shelters. For fuel cell and hydrogen research, it provides precise measurement of hydrogen and oxygen feed rates. In general industrial settings, it finds use in measuring low steam flows for small tracing lines, instrument air purge flows, and the injection of chemical additives (e.g., corrosion inhibitors, odorants) into pipelines at precisely controlled rates. Essentially, any application involving small, critical gas or liquid flows where traditional DP installations are cumbersome or unreliable is a prime candidate for the EMERSON 8750-CA-NS.
Related Products
EMERSON 8750W-CA-NS: A wafer-style version of the integral orifice flowmeter, designed for installation between standard ANSI flanges, offering easier installation and maintenance in existing piping.
EMERSON 8750C-CA-NS: A compact, low-flow DP transmitter with remote seals (capillary systems) for applications with high-temperature, viscous, or slurry fluids where an integral orifice is not suitable.
Rosemount™ 3051S Series: Emerson’s premier multi-variable pressure transmitters, which can be configured with remote seals for flow measurement but are more general-purpose and modular.
Rosemount™ 8700 Series: Magnetic flowmeters from Emerson for conductive liquid applications, serving a different measurement technology.
Rosemount™ 8800 Series: Vortex flowmeters from Emerson for liquid, gas, and steam flow, suitable for higher flow rates than the 8750 integral orifice.
EMERSON 475 Field Communicator or AMS™ Device Manager: The handheld and software tools used to configure, calibrate, and diagnose the 8750-CA-NS transmitter.
EMERSON Orifice Plate & DP Transmitter (separate components): The traditional, non-integrated assembly that the 8750-CA-NS is designed to replace for low-flow applications.
Thermal Mass Flow Meters (e.g., Emerson’s F-Series): An alternative technology for gas mass flow measurement at low rates; the 8750-CA-NS offers higher pressure capability and multi-variable outputs.
Reviews
There are no reviews yet.
Be the first to review “EMERSON 8750-CA-NS Ultra-Low Flow Differential Pressure Transmitter” Отменить ответ
Reviews
There are no reviews yet.