Rheotherm - Duct Flow Meters For Air and Process Gas Brochure

Rheotherm mass flow sensing insertion probes for air and most other non-condensing gases, including corrosive and explosive gases, are easy to install and provide long-term service with little or no maintenance. Product SummaryDuct Flow Meters for Air and Process Gas• Accurate mass flow• No moving parts• Wide rangeability• Maintenance-free• Easy installationRHEOTHERM®FLOW INSTRUMENTSThermal Mass Method Our insertion flow sensors have two stainless steel flow sensing tips welded to the probe shaft. One tip has a heated RTD in it and the other an unheated RTD. The temperature differential between the two RTDs provides the primary flow signal: at high flow rates the differential is lower as flow removes more heat, and at low flow rates the differential is higher, as flow removes less heat. Nothing touches the gas but the metal probe and tips.Process ConnectionInstalled through the pipe or duct wall, connections can be made with NPT, flange, bore-through compression, or sanitary fittings. The probes can be installed in horizontal or vertical pipes. Electron-ics with optional display may be integral to the sensor or remotely mounted up to 200 feet from the sensor.Turndown RatioTypical calibration ranges are 10:1 (options up to 200:1). Over-ranging cannot damage the sensors.Common uses include vent air, stack gas, and digester gas. The output units can be in mass flow, standard volumetric flow, or velocity. Options for hazardous (classified) locations are available. The stainless steel construction and lack of moving parts make it ideal for rugged industrial environments.Electronics can be installed remotely from sensors.For assistance with any flow application, contact an application engineer at INTEK, the leader in precision thermal flow metering.Call 888-LOW FLOW (569-3569).INTEK, INC.751 Intek WayWesterville, OH 43082-9057Phone: 614-895-0301Fax: 614-895-0319sales@intekflow.comwww.intekflow.comINTEK, Rheotherm and RheoVac are registered trademarks of INTEK, Inc. © 2011 by INTEK, Inc. Printed in U.S.A. Specifications subject to change Bulletin #DFM-1 General SpecificationsApplications Air ducts and process gas pipes Line Size 1” to 36” diameterCalibration Units Mass, standard volume or standard velocityFlow Rate Range 50 to 25,000 ft/minTemperature Limits (Specify requirements) Sensor: Standard: 0 to 212°F (-18 to 100°C) Optional: -40 to 500°F (-40 to 260°C) Electronics: 0 to 120°F (-18 to 49°C) Pressure Limits Varies with process connection rating Repeatability ± 0.5% of readingCalibration Accuracy ± 2% of reading typicalFM Options for Hazardous Locations See Product Summary # FM for approved classes, divisions and groupsDuct Flow Meter Features and Options Standard OptionsTurndown ratio 10:1 Up to 200:1Process connection: 1” NPT flanges, sanitary, hot tapWetted surface: 316 SS Hastelloy C-276®, Monel®Output: 4-20 mA 0-10 or 0-5 Vdc, voltage frequency or open collector, 1 or 2 SPDT relaysDisplay: None flow rate, total flow, fluid temperatureInput power: 24 Vdc 85-250 Vac (Remote electronics only)Enclosure: NEMA 4X, NEMA 4, NEMA 7 NEMA 7 (Remote electronics only)Hastelloy is a registered trademark of Haynes International, Inc.Monel is a registered trademark of Special Metals CorporationWhat if there is little or no straight run available?Rheovec™ Sensor HeadsThe turbulence and swirling of air and gas in short-run and curved ducts create accuracy problems for ordinary flow sensors due to fluctuating velocities. The Rheovec™sensor head, with its unique honeycomb structure around the probe tips, eliminates off-axis error, enabling highly repeatable true mass flow rate measurement. See Product Summary #VEC-1 for furtherinformation.