E&H 6F5B thermal mass flowmeter

E&H 6F5B thermal mass flowmeter

Proline t-mass F 500 Thermal Mass Flowmeter – Model Series 6F5B

Inline Remote-Mount Gas Flowmeter with Up to 4 I/Os for Demanding Industrial Applications

1. Product Overview

The Endress+Hauser Proline t-mass F 500 (order code root 6F5B) represents the next-generation remote-mount inline thermal mass flowmeter engineered for direct mass measurement of utility gases, process gases and gas mixtures across DN 15 to DN 100 pipelines. Building upon decades of thermal dispersion expertise, the 6F5B series delivers uncompromised long-term stability with an innovative remote transmitter architecture that maximizes installation flexibility and operational safety in the most demanding industrial environments.

The patented sensor design of the t-mass F platform provides industry-leading measurement stability in thermal inline mass flow applications. Real-time compensation for fluctuating process conditions — including temperature excursions, pressure transients, flow direction reversals, and gas composition drift — ensures consistent, reliable readings across the entire measurement envelope. The remote transmitter design separates the electronics housing from the measuring section, enabling installation in confined spaces, high-temperature zones, or vibration-prone locations while keeping the operator interface accessible in safe, convenient areas.

Each 6F5B-series flowmeter is equipped with Heartbeat Technology — an integrated verification and diagnostic suite that continuously validates measurement integrity and generates compliant audit documentation without process interruption. This feature significantly reduces maintenance costs and downtime while supporting regulatory compliance requirements.

Distributor: ST-YUKE CO., LIMITED — Authorized supplier of genuine Endress+Hauser instrumentation with global shipping capabilities and comprehensive technical support.

2. Technical Specifications at a Glance

*Specifications derived from TI01502DEN_0323-00 Technical Information document.*

3. The Remote-Mount Advantage: Why Choose the F 500 Series

Unlike compact (all-in-one) thermal mass flowmeter designs, the 6F5B series features a true remote transmitter configuration. The sensor (mounted directly in the pipeline) connects to the transmitter (located up to 100 meters away) via a standard shielded cable. This architectural choice delivers several critical benefits:

Installation Flexibility — The transmitter can be positioned at grade level or in an instrument cabinet while the sensor remains in the pipe run. This is particularly advantageous for elevated pipework, confined valve stations, or areas with restricted access.

Thermal Isolation — Electronics are vulnerable to high ambient temperatures. By remotely locating the transmitter, the 6F5B can measure process gases up to +180°C while keeping sensitive electronics at a safe operating temperature.

Vibration Resistance — The remote design removes mass from the pipe, reducing mechanical stress and eliminating vibration-induced measurement errors common with heavy compact units on vibrating pipework.

Maintenance Accessibility — Operators can configure, verify, and troubleshoot the device from a convenient walk-up location without climbing ladders or entering hazardous zones.

Up to 4 Freely Configurable I/Os — The remote transmitter accommodates up to four input/output channels, each independently assignable to 4–20mA HART, pulse/frequency outputs, status inputs, or Modbus RS485 communication. This flexibility reduces inventory complexity — a single 6F5B hardware platform serves multiple application requirements.

4. Seven Size Variants — Complete Lineup of the 6F5B Series

The 6F5B series spans seven distinct nominal diameter configurations, each engineered for specific flow capacity requirements and application scenarios. Below is a detailed breakdown of every available variant:

4.1 Model 6F5B15 — DN15 (½ inch)

The smallest variant in the series, 6F5B15 is optimized for low-flow applications demanding exceptional measurement sensitivity. Its reduced bore diameter enables precise resolution of minimal gas flow rates, making it the preferred choice for analytical instrumentation, pilot plants, pharmaceutical gas dosing, and specialty gas blending. Typical measurable range: 0.5–45 kg/h depending on gas type. An example order code: 6F5B15-AAIBAAAAFAAAAAHAAASGA2+AA (decoded in detail below).

4.2 Model 6F5B25 — DN25 (1 inch)

The 6F5B25 configuration serves as the workhorse for medium-flow industrial gas measurement. Particularly prominent in chemical processing environments, this variant delivers reliable performance across fluctuating process conditions with minimal susceptibility to gas composition variations. The 1-inch bore strikes an optimal balance between flow capacity and measurement resolution for most utility gas monitoring applications.

4.3 Model 6F5B40 — DN40 (1½ inches)

Engineered for continuous, high-throughput gas flow monitoring, 6F5B40 excels in production line environments where stable, uninterrupted flow data acquisition is critical. This variant is frequently deployed in energy management systems, compressed air networks, and combustion air monitoring. Its larger bore diameter maintains low pressure drop while accommodating elevated flow velocities.

4.4 Model 6F5B50 — DN50 (2 inches)

The 6F5B50 offers expanded flow capacity while retaining the series‘ signature measurement accuracy. This 2-inch variant is widely specified for natural gas distribution sub-metering, industrial boiler feed air monitoring, and nitrogen blanketing systems. Example order codes: 6F5B50-AAIBAEAFAASAAASGA2+, 6F5B50-AAIBAAAAFAAAAAHAAASGA2+AA.

4.5 Model 6F5B65 — DN65 (2½ inches)

Stepping into larger pipeline applications, 6F5B65 addresses high-flow measurement scenarios commonly encountered in large-scale chemical production lines and power generation facilities. This variant maintains stable operation under harsh conditions and delivers reliable data integrity even with aggressive or contaminated gas streams. Example configuration: 6F5B65-AAIBAEAFAASAD2SGA2+AK.

4.6 Model 6F5B80 — DN80 (3 inches)

The 6F5B80 configuration extends the measurement envelope to 3-inch nominal diameter, accommodating substantial gas flow rates in main process headers and utility distribution networks. This variant is frequently specified for plant-wide compressed air monitoring, flare gas measurement, and large-scale HVAC airflow tracking. Example order code: 6F5B80-AAIBAEAFAASAAASGA2+AKCS.

4.7 Model 6F5B1H — DN100 (4 inches)

At the top of the size range, 6F5B1H (DN100 / 4 inches) represents the maximum bore diameter available in the inline t-mass F 500 platform. This variant is specifically designed for large-diameter gas flow applications where measurement precision must be maintained despite increased volumetric throughput. It is particularly well-suited for main natural gas intake lines, large-scale combustion air systems, and energy-intensive process gas monitoring.

5. Order Code Breakdown: 6F5B15-AAIBAAAAFAAAAAHAAASGA2+AA

To facilitate precise device configuration, specification verification, and procurement, each 6F5B-series flowmeter carries a comprehensive order code that encodes every built-in feature. The following analysis decodes the complete order code structure using the example 6F5B15-AAIBAAAAFAAAAAHAAASGA2+AA:

Root Code: 6F5B15

6F5B = Proline t-mass F 500 series product family

15 = Nominal diameter DN15 (½ inch)

Feature Breakdown (Sequential positions after hyphen):

This order code breakdown follows the Endress+Hauser product configuration schema. For verification of any existing device or to build a custom configuration, the order code can be entered into the Endress+Hauser Device Viewer (www.endress.com/deviceviewer) to retrieve complete specification details.

Additional example order codes in the field:

6F5B25-NDEBAAAFABSAD2SGA2+AKJA — DN25, flameproof enclosure, 4–20mA+HART

6F5B1H-AAIBAEAFAASAAASGA2+ — DN100, bidirectional sensor, SIL-capable configuration

6F5B50-AAIBAEDFAASAD2SGA2+AA — DN50, extended diagnostics package

6. Measuring Principle and Gas Engine Technology

The thermal mass flow measurement principle employed by the 6F5B series is based on the cooling effect of a flowing gas stream passing over a heated resistance thermometer (PT100). Two PT100 sensors reside within the flow stream: one serves as a temperature reference monitoring the actual process temperature, while the other is maintained at a constant differential temperature above the process temperature by controlled heating current. As gas mass flow increases, more heat is extracted from the heated sensor, requiring greater electrical current to maintain the temperature differential. This heating current is directly proportional to the mass flow rate — with no separate pressure or temperature compensation required under stable gas composition conditions.

The integrated Gas Engine software database, pre-loaded into every 6F5B unit, contains specific thermodynamic properties for 21 standard gases. The Gas Engine enables:

Air-based factory calibration — eliminating expensive real-gas calibration requirements

Precise conversion from air to any target gas without recalibration

Dynamic pressure and temperature compensation during operation

Calculation of gas mixture properties based on up to 8 component percentages

Supported gases include: Air, Nitrogen (N₂), Oxygen (O₂), Hydrogen (H₂), Carbon Dioxide (CO₂), Methane (CH₄), Propane (C₃H₈), Butane (C₄H₁₀), Ethane (C₂H₆), Ethylene (C₂H₄), Argon (Ar), Helium (He), Ammonia (NH₃), Carbon Monoxide (CO), Hydrogen Sulfide (H₂S), Chlorine (Cl₂), Hydrogen Chloride (HCl), Krypton (Kr), Neon (Ne), Ozone (O₃), and Xenon (Xe).

7. Wetted Materials and Process Connections

The 6F5B series employs corrosion-resistant materials suitable for a wide range of industrial gas applications:

Process connection standards available:

EN flanges: DN15 to DN100, PN16/25/40

ASME flanges: ½ to 4 inches, Class 150/300

JIS flanges: 10K/20K

Threaded connections: NPT ½ to 4 inches; BSPT R½ to R4

8. Heartbeat Technology and Integrated Verification

Heartbeat Technology is a cornerstone feature of the 6F5B series, providing three integrated functions:

Heartbeat Monitoring — Continuously monitors the device‘s internal health status, tracking sensor drift, electronics integrity, and communication stability. Alerts are generated when predefined thresholds are exceeded, enabling predictive maintenance before failure occurs.

Heartbeat Verification — On-demand verification of measurement accuracy without process interruption. The device executes a self-diagnostic routine and generates a compliance report suitable for audit requirements. No external reference devices or process shutdowns are required.

Heartbeat Extended Verification — Available as an application package (option EB), this extends verification capabilities to include sensor characterization validation and gas property verification, providing the highest level of measurement confidence for critical applications.

This technology significantly reduces the total cost of ownership by eliminating routine calibration removal and external verification expenses while maintaining full regulatory compliance documentation.

9. Installation and Operational Requirements

To ensure optimal measurement performance, the following installation guidelines should be observed:

Inlet/Outlet Straight Runs — For inline thermal mass flowmeters, a minimum of 5 × DN upstream straight pipe and 3 × DN downstream straight pipe is recommended, with longer runs (10 × DN) advised in the presence of bends, valves, or reducers.

Orientation — The 6F5B series can be installed in any orientation (horizontal, vertical, or inclined). However, the measuring tube must remain fully filled with the gas medium; condensation or liquid entrainment should be avoided as thermal mass measurement is calibrated for single-phase gas flow.

Cable Length — The remote transmitter connects to the sensor via a standard shielded cable. Maximum cable length is 100 meters (330 feet). For installations requiring longer separation, consult the technical documentation for signal integrity considerations.

Environmental Conditions — The remote transmitter housing (IP66/67, Type 4X) is suitable for outdoor installation. The operating ambient temperature range is –40 °C to +60 °C (–40 °F to +140 °F).

Electrical Connections — Standard M20 × 1.5 cable gland entries accommodate signal and power cabling. HART communication requires a minimum load resistance of 250 Ω between device and power supply. For Modbus RS485 variants, proper termination resistors and shielded twisted-pair cabling are required.

10. Supported Communication Protocols and I/O Configurations

The 6F5B transmitter supports two primary communication protocols:

HART (Highway Addressable Remote Transducer) — The most widely adopted industrial communication protocol for process instrumentation. The HART version provides 4–20mA analog output with digital HART communication superimposed on the same two wires. Device configuration, diagnostic data, and process variables are accessible via HART.

Modbus RS485 — The digital fieldbus version eliminates analog conversion, providing direct digital transmission of all measured variables, diagnostic data, and configuration parameters. Modbus RS485 supports multi-drop installations, reducing wiring complexity in systems with multiple instruments.

I/O Configuration Flexibility — Up to four I/O channels can be independently configured. Typical configurations include:

One 4–20mA HART output + one pulse/frequency output + two status inputs

Two 4–20mA outputs + one pulse output + one status input

Modbus RS485 digital communication with up to three additional configurable I/O channels

11. Supported Gases and Application Suitability

The 6F5B series is suitable for a wide range of industrial gas measurement applications:

For custom gas mixtures not pre-loaded in the Gas Engine, the device can be configured using up to 8 individual gas components with user-defined percentage splits, with the Gas Engine calculating mixture properties dynamically during operation.

12. Why Source the 6F5B Series from ST-YUKE CO., LIMITED

ST-YUKE CO., LIMITED is a recognized distributor of Endress+Hauser instrumentation, providing the full Proline t-mass F 500 series (6F5B15, 6F5B25, 6F5B40, 6F5B50, 6F5B65, 6F5B80, 6F5B1H) with:

Genuine product certification — Every unit sourced directly from Endress+Hauser manufacturing facilities

Global shipping — Express delivery to major industrial centers worldwide

Technical pre-sales support — Order code configuration assistance and application engineering

Competitive pricing — Volume discounts available for OEMs and system integrators

Post-sales documentation — Complete technical information packages (TI, BA, KA, GP) provided with each shipment

For inquiries, quotations, or technical consultation regarding any 6F5B-series model, contact ST-YUKE CO., LIMITED directly.

13. Downloads and Supporting Documentation

The following official Endress+Hauser documents provide complete technical information for the 6F5B series (available via www.endress.com or through ST-YUKE CO., LIMITED):