Fluid Components International (FCI) has launched its ST80 series of thermal mass flow meters, raising the bar for range, accuracy, extended service life, reliability and application-matched solutions for air/gas flow measurement.

FCI’s patent-pending Adaptive Sensor Technology (AST) for the ST80 features an innovative hybrid sensor drive, combining constant power and constant temperature thermal dispersion sensing technologies in the same instrument for the first time. Complementing this is a choice of four different flow sensor element designs to ensure best installed performance, including FCI’s new wet gas solution.

When operating in AST mode, the ST80 measures in constant temperature mode during start-up and at lower flow ranges, then seamlessly shifts into constant pressure mode at mid-range and higher flow rates. The result is a ‘best-of-both-technologies’ performance delivering extremely fast response with extended measuring ranges at low power consumption to maximise sensor reliability and reduce instrument energy expenses.

The ST80 features FCI’s rugged no-moving-parts flow element design, providing direct measurement with just a single penetration. This saves space in the plant and eliminates unnecessary installation and maintenance expenses. It also prevents the performance degradation encountered with other flow technologies, which require the addition of expensive temperature and pressure sensors to compute an inferred mass flow.

It has no moving parts to plug or foul and clean, so it delivers extensive lifecycle cost savings over higher-maintenance technologies. The result is accurate and highly repeatable mass flow measurement at the lowest total installed cost. In today’s complex process control schemes, the ST80 provides the accurate air and gas flow measurements essential for process consistency, quality, plant safety and environmental compliance.

It is accurate to ±1% of reading, ±0.5% of full scale and ±0.5% of repeatability. The turndown ratio is factory preset to meet the requirements of the application from a minimum of 2:1 up to 100:1. This meter operates over a wide flow range: the insertion style configuration range is 0.07 to 305m/s and the in-line style configuration range is 0.01 to 3140m3/h.

While a single calibration is sufficient for many processes, the ST80 can provide two unique calibration groups, for example, two different compositions of mixed gases or two completely different gases. This is especially helpful in processes that are affected by seasonal environmental temperature changes, such as wastewater treatment digester gas and landfill gas reporting or recovery systems.

A three-point calibration drift self-test feature is standard. The tests, run at a low, mid and upper points across the flow range, can be performed on demand from the front panel buttons or programmed to run automatically based on day and time to save time and maintenance expenses. The self-test is performed in-situ – there is never a need for the ST80 to be removed or retracted from process piping, or to suspend the processes’ operation. There are no unnecessary spares sitting on the shelf, or shipping costs and lab fees for unneeded recalibration service.

The ST80 features multiple outputs to interface with control systems and/or set-up or configuration devices. The standard ST80 meter configuration includes dual 4-20mA, NAMUR NE43 compliant analogue outputs, HART (version 7) and Modbus 485. Optionally available are Foundation Fieldbus and PROFIBUS PA. All digital bus communications are full two-way I/O.

It is offered with or without display, or with display and through-the-glass user programming buttons. The display is a best-in-class, backlighted LCD, providing both digital and bar graph readout of the flow rate and temperature, totalised flow, alarm conditions, diagnostics feedback and even a user-defined label field.

It is offered in a wide range of process connections, mounting and installation options, including compression fittings, flanged and packing glands, and with the transmitter/electronics integrally mounted with the flow element or remotely mounted up to 300m apart. It is suitable for a wide range of applications in pipe diameters from 25mm to 2.5m, from compressed air to hydrocarbon gases, single process or specialty gases to biogas mixtures and more. It has a temperature measurement range up to 454°C. The transmitter enclosure is NEMA 4X/IP67 rated, selectable for NPT or metric conduit port threading and is available in both aluminium and stainless steel.

It can be ordered for either 24V DC or AC input powering. The DC unit is a fully isolated supply that operates over a wide 19.2 to 28.8V DC range. The AC unit will operate from 85 to 265V AC to ensure operation worldwide. As with all FCI thermal flow meters, the ST80 requires less than 10W maximum power, half that of other thermal flow meters, which minimises plant energy costs and enhances service life.

It features extensive global HazEx agency safety approvals for potentially dangerous environment installations. FCI products undergo rigorous agency testing and obtain their approvals on the entire instrument, not just the enclosure. Approvals include FM, FMc, ATEX and IECEx, and the meter is CE marked. CPA, NEPSI, EAC (TR CU) and CRN approvals have been submitted and are pending. The ST80 also has been independently evaluated to meet and comply as a SIL 1 device.

AMS Instrumentation & Calibration
03 9017 8225


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