Product/Service

Thermal Mass Flowmeter

Source: Fluid Components International (FCI)
The latest addition to the company's flowmeters combines the best features and accuracy of its sensor head designs and microprocessor-based electronics to set a new standard for both price and performance.
The latest addition to the company's flowmeters combines the best features and accuracy of its sensor head designs and microprocessor-based electronics to set a new standard for both price and performance. The ST98 Flowmeter Series targets rigorous gas flow applications in a wide range of industries including chemical, oil and gas, pulp and paper, pharmaceuticals, wastewater, power generation and food.

Performance
The ST98 sensing element measures direct mass flow in gases over a wide range, avoiding the need for temperature and pressure compensation that can downgrade performance. Flow ranges start at 0.21 NMPS for the insertion model and 0.01 NCMH for the in-line version.

The meters combine low flow sensitivity with a 100:1 turndown and can measure mass velocities up to 180 NMPS. Accuracy is ± 1% of reading plus ± 0.5% of full scale. Repeatability is ± 0.5% of reading. The sensor operates over a process temperature range of -40 to 177°C, and pressure ranges of 0 Bar(g) to 17 Bar(g).

Features
The ST98 Series offers easy access to termination points and communication ports, and integral or remote electronics. Enclosures are either weather resistant, or alternatively weather resistant and explosion proof to EExd IIc, T4 and IP66 standards. An RS232C serial port interfaces with the company's FC88 Communicator, a remote computer, or any ASCII terminal. Standard analog outputs include 4-20mA, 0-5VDC, or 0-10VDC.

Applications include natural gas and methane monitoring, biogas flow from digesters and landfill, airflow balancing, nitrogen blanketing, compressed air and other industrial gases. The company maintains an air and gas calibration laboratory traceable to NIST for the calibration of meters to new and existing applications.

Operating principal
The measurement compares a heated resistance thermometer (RTD) with a reference RTD. The temperature difference between the two is proportional to the process mass flow rate. Standard 316 stainless steel flow elements have adjustable insertion lengths in sizes of 2.5cm to 15cm, 2.5cm to 30.0cm or 2.5cm to 53cm. The standard process connection is a male 3/4 inch NPT compression fitting. Inline configurations of DN 25, DN 40, and DN 50 are also available.

Fluid Components International, 1755 La Costa Meadows Dr., San Marcos CA 92069. Tel: 760-744-6950. Fax: 760-736-6250.