Optimize Gas Flow Control with the d·flux Multiparameter Mass Flow Meter

The d·flux multiparameter mass flow meter gives unparalleled precision in controlling gas flow.

• Measuring and controlling five process variables: mass flow, volumetric flow, temperature, pressure, and density
• High precision of +/-0.3% of the user’s full scale +/–0.5% of the measured value
• Five sensor options offer increased versatility and economy
• Multigas Capability: Pre-program up to 15 gases or gas mixtures
• Monitor and operate meter operations effortlessly from the mobile device with the free Android App (Bluetooth)
• Flow rates up to 1508 slpm (Air) Other gases, depending on conversion. Up to 3120 for hydrogen

Overview

d·flux High Flow Accuracy Delivers Revolutionary Performance

The demands on scientific and industrial flow measurement instruments have never been greater. Precise measurement of high flows and the ability to rapidly and accurately switch between pure gases and gas mixtures are essential. Reliable performance over time is critical in factory and laboratory settings, along with the assurance that suppliers will provide support when unexpected challenges arise.

Sierra's d·flux offers a stable and high-performance package. The d·flux mass flow device, made of stainless steel or aluminum, accurately measures five process variables: mass flow, volumetric flow, temperature, pressure, and density. It uses genuine physical calculations using complex 3D polynomial data tables to provide the required flow data. These diagnostics make switching gases faster and easier without sacrificing accuracy.

Monitor and Adjust on the Go

Sierra Flow Connector, a user-friendly Bluetooth app by d·flux, is available for free on Google Play. Users can safely connect to d·flux using the Android handset to create and edit profiles (settings). While working in the field, users can change the flow range and dynamic range, filter settings, alarms and warnings, and various other important factors.

Wide Application Scope

d·flux’s precision gas management and robust capabilities make it suitable for a wide range of applications, including:

• Hydrogen production: Fuel cells, generation, custody transfer, storage and transportation, blending, and process monitoring and control are some examples of applications
• Biopharmaceutical production: Microorganisms can be cultivated and grown using d•flux in bioreactors for use in genetic engineering, drugs, and vaccines
• Carbon capture and storage: Calculate the amount of CO₂ generated when biomass or fossil fuels are burned in chemical bioenergy facilities
• Nuclear energy: Utilize d•flux to monitor Argon blanketing gas in a welding chamber
• Gas injection: Measure the CO₂ utilized to regulate pH in bioprocessing and wastewater

Sierra Flow Studio

Advanced Modbus communication and analog output are Sierra’s d·flux features. Digital communications options include EtherCAT and PROFINET. Sierra Flow Studio is a sophisticated PC software that enables Modbus communication with the d-flux device within a Microsoft Windows environment. Users can download it for free.

The Differential Pressure Advantage

Sierra’s d·flux measures differential pressure across a laminar flow element. The sensors monitor the pressure differential, absolute pressure, and gas temperature.

Using this information, the internal electronics determine the mass flow through the device. The laminar flow meter has a unique benefit because of its linear relationship between flow rate and generated pressure drop. When a control valve and a PID Controller are added to the meter, it becomes a mass flow controller. Users specify a setpoint to start a repeatable, stable mass flow. The flow rate is unaffected by pressure or temperature variations.

Stainless Steel or More Affordable Aluminum Bodies. The d·flux Series comes in stainless steel or aluminum flow bodies. The aluminum body decreases the devices' weight and expenses while retaining great specs and functionality. The anodized aluminum body is corrosion-resistant and suitable for most gases.

Sensor Flexibility

d·flux provides flexible and cost-effective sensor materials for gas flow applications, ensuring high accuracy:

• Core Sensor:
  • The Core Sensor is a high-tech differential pressure sensor that is only usable with air, nitrogen, argon, and oxygen gases. One modular epoxy-based housing contains the absolute pressure sensor and the pressure differential sensor
  • A1 Core: ± 0.5% of user full scale ± 1% of measured value
• Prime Sensor: All wetted components are stainless, and the entire structure is made of SS316L. A fully welded stainless housing houses the absolute pressure and differential sensors. It is strong and incredibly resistant to corrosion. There are two options for it:
  • B1 Prime: +/-0.3% of user full scale +/-0.7% of measured value 
  • B2 Prime: Prime high accuracy +/-0.3% of user full scale +/-0.5% of measured value
• Prime Hydrogen Sensor: The Prime Hydrogen Sensor is identical to the Prime Sensor, except its membrane is gold-coated. Because H2 passes through 316 membranes, this qualifies the sensor for use in H2 applications. A high-performance sensor with optimized accuracy is also available.
  • B3 Prime H2: +/-0.3% of user full scale +/-0.7% of measured value
  • B4 Prime H2 high accuracy: +/-0.3% of user full scale of measured value

Note: User full scale = ~70…100% standard range.

Product Benefits

• Five process variables—mass flow, volumetric flow, temperature, pressure, and density—are measured and managed by a single device
• Flow rates up to 1508 slpm (Air)
• Other gases, according to conversion, for example, up to 3120 for Hydrogen
• High Accuracy – Up to +/-0.3% of user full scale and +/-0.5% of measured value
• Multigas Capability – Pre-program 15 gases and/or gas mixes
• Monitor and regulate meter operations effortlessly from the mobile device with the free Sierra Flow Connector App
• Available in stainless steel or aluminum bodies
• Cost-effective- Five sensor alternatives to fit the user’s budget
  • Core sensor (economical solution) for air, nitrogen, oxygen, and argon
  • Prime Sensor is appropriate for all gases. (2 variants are available)
  • Gold-plated Prime sensor—perfect for hydrogen (2 variants are available)

• Digital communications - Advanced Modbus and analog output. PROFINET and EtherCAT are provided as alternatives
• Minimize uncertainty with Autotare - dflux controllers use an innovative algorithm to detect no flow and then zero (tare) for maximum performance
• With d·flux, users may create up to 15 custom application profiles and store individual application details. Each profile has its totalizer
• Sierra Flow Studio Software allows communication with d·flux in Microsoft Windows via Modbus

Specifications

• Multiparameter Measurement and Control (mass flow, volumetric flow, temperature, pressure, and density)
• Accuracy (5 Sensor options)
  • A1 Core: ± 0.5% of user full scale ± 1% of measured value
  • B1 Prime: ± 0.3% of user full scale ± 0.7% of measured value
  • B2 Prime high accuracy: ± 0.3% of user full scale ± 0.5% of measured value
  • For Hydrogen applications:
  • B3 Prime H2: ± 0.3% of user full scale ± 0.7% of measured value
  • B4 Prime H2 high accuracy: ± 0.3% of user full scale ± 0.5% of measured value User full scale = ~70…100% standard range

Sensor Options:

• Prime H2 sensor: Appropriate for all gases, including H2 (sensor with a gold coating). With FKM and EPDM only
• Core sensor: Appropriate for argon, oxygen, nitrogen, and air. Only with EPDM and FKM
• Prime sensor: Appropriate for all gases, with the exception of H2. offered with FFKM, EPDM, and FKM

Both stainless steel and aluminum bodies are available for all sensors. Additionally, prime sensors come with a high-accuracy option.

Sensor Stability: After tare, less than 0.2% of the measured value every year

Repeatability: ± 0.2% of factory full scale

Flow ranges: up to 1508 slpm (Air)

Other gases according to conversion (ex. Up to 3124 slpm for hydrogen)

Source: Sierra Instruments

Pressure: 1 to 200 psia (1 to 14 bar a)

Response time:

• Meter: 120 msec 
• Controller: 2000 msec

Update time mass flow value: 10 msec Sensor sample rate: 1 msec. / 4 msec. with optimized filter settings

Warm-up Time: <2 seconds for full accuracy

Turndown (Dynamic Range): For most gases, 1:100; with Automated Dynamics, 1:1000 (only the meter). A set dynamic range or an automated range can be chosen during the order process. The Sierra Flow Connector App allows users to modify this configuration anytime.

Higher pressures result in a smaller dynamic range since the dynamic range is dependent on both gas and pressure.

Operation Pressure: 1 to 200 psia (1 to 14 bar a)

Gas

Source: Sierra Instruments

1. The given flow ranges, unless otherwise indicated, are for an equivalent airflow at 70 °F (21.11 °C) and 1013.25 bar a (760 mmHg). The digital communication interface or the Sierra Flow Connector App allows users to choose from additional common flow, temperature, and pressure units. The d•flux instruction instructions contain more details
2. The standard list above can include more gases or gas mixtures. A maximum of 15 gases can be stored per unit. Except for air, stored gases can be substituted with another gas or gas mixture. Through the digital communication interface or the Sierra Flow Connecter App, users can choose from pre-programmed gases and mixtures. Please get in touch with the factory for information on other gases, gas mixtures, and reference conditions. Only appropriate for clean, dry gases
3. O₂ cleaning is optional and available upon request. Please refer to the gas list for additional gases and ranges

Gas Profiles: There are up to 15 user-programmable profiles. Profiles are pre-defined configurations that let the customer specify the gas, range, dynamics, totalizers, engineering units, and reference conditions for up to 15 different applications. PID settings are for the controller only.

Media: All gases and gas mixtures that are compatible with the selected materials and have available data in the NIST REFPROP database are supported. For more details, contact the factory.

Sierra Flow Connecter App: Use our free Android app (Bluetooth) to quickly access and configure device parameters.

Sierra Flow Studio: Utilize software to access sophisticated monitoring, diagnostics, and reporting for every facet of d•flux.

Power Supply Meter: 15-36 VDC, (200 mA@24 VDC, regulated) / Controller: 24 VDC ±10%, (2000 mA@24 VDC, regulated). Power in through M8-4P connection or optionally through D-sub connection (ripple should not exceed 100 mV peak-to-peak). Note: We recommend that the body of this unit is properly connected to ground.

Temperature (environment/gas): –4 °F to 140 °F (–20 °C to 60 °C)

Humidity Gas: 0-95% Rh (non-condensing)

Long-term Stability: Typical < 0.2% of measured value / year after tare

Pressure Sensitivity: Prime and Prime H2 sensor: ± 0.05% factory full scale per bar (typical air)

Core Sensor: ± 0.08% of factory full scale + 0.1% of measured value per bar (typical air)

Temperature Sensitivity: <0.02% factory full scale (maximum flow range of the device) per 1 °C of inlet gas temperature at 100 psia (7 bara).

Accuracy Temperature Typically ± 0.5 °C (not certified)

Accuracy Absolute Pressure <0.5% MV (not certified)

Wetted Materials Seals:

• B3 + B4 Prime H2 sensor: Stainless-steel 316L (1.4404) with gold coating
• FKM, EPDM, or FFKM (valve seat).
• A1 core sensor: Stainless-steel 316Ti (1.4571), silicon, gold, glass, silicone encapsulation, PBT. 30GF, ceramics
• Full FFKM version upon request
• Body: Aluminum or Stainless-steel 316L (1.4404)
• Valve (controller): 316 (1.4401), 416 (1.4005), 430F (1.4104).
• Inlet filter: Stainless-steel 316 (1.4401), fastening stainless-steel (1.4122) or equivalent
• B1 + B2 Prime sensor: Stainless-steel 316L (1.4404)

Approvals:

• RoHS/REACH: All components comply with Directive 2002/95/EC (RoHS) and the REACH guidelines.
• EMC: IEC/EN 61326-1, IEC/EN 61000-6-2/4
• Material Certificates: Contact the factory
• FDA Compliance: Contact the factory
• PED: Fully compliant. Since the unit has 1" process connection, complies with the SEP, as defined in article 4, paragraph 3 of the Pressure Equipment Directive (PED) (2014/68/EU)