E&H 9W4B ultrasonic flowmeter

E&H 9W4B ultrasonic flowmeter

Introduction: The Noninvasive Flow Measurement Standard

The ENDRESS + HAUSER Proline Prosonic Flow W 400 series, identified by the product root 9W4B, represents the pinnacle of noninvasive ultrasonic flow measurement technology. This clamp-on flowmeter combines the advanced Proline 400 transmitter platform with proven ultrasonic transit time measurement principles, delivering accurate, maintenance-free flow monitoring without any process interruption.

Unlike traditional inline flowmeters that require cutting into pipelines, stopping production, or modifying existing infrastructure, the 9W4B series clamps directly onto the outside of the pipe. This approach eliminates leakage risks, pressure loss, and mechanical wear while maintaining measurement integrity across a vast range of pipe diameters from DN 15 to DN 4000 (½ to 160 inches). Whether your application involves potable water distribution, raw sewage monitoring, industrial process water, cooling water systems, or hydropower plant operations, the Prosonic Flow W 400 provides reliable bidirectional flow measurement independent of fluid density, electrical conductivity, pressure, or temperature.

This comprehensive technical documentation serves as your authoritative engineering reference for selecting, specifying, and implementing the E+H 9W4B clamp-on ultrasonic flowmeter for your specific application requirements.

Product Series Overview: 9W4BA0 / 9W4BA1 / 9W4BA2

The 9W4B product family is organized into three distinct variants within the Prosonic Flow W 400 series: 9W4BA0, 9W4BA1, and 9W4BA2. All three models share the core clamp-on ultrasonic measurement principle, Heartbeat Technology platform, integrated web server capabilities, and compatibility with the full DN 15–4000 pipe diameter range. The primary differentiation lies in the number of sensor sets (measurement paths) and corresponding accuracy optimization.

The 9W4BA0 serves as the fundamental configuration, delivering reliable single-path measurement for standard water and wastewater applications. The 9W4BA1 offers an upgraded single-path configuration with enhanced feature sets. The 9W4BA2 represents the premium configuration, incorporating two complete sensor sets (four transducers) for dual-path measurement, providing enhanced accuracy, redundancy, and the ability to compensate for disturbed flow profiles-17.

All three 9W4B variants operate on the ultrasonic transit time difference principle. Ultrasonic signals are transmitted through the pipe wall and liquid medium; the time difference between upstream and downstream signal propagation is directly proportional to flow velocity. This method requires no moving parts and imposes no pressure drop, delivering truly maintenance-free operation throughout the entire product lifecycle-12.

Complete Order Code Configuration: 9W4BA0-AALHFNAABAAAACA2

For engineers, procurement specialists, and system integrators requiring a concrete specification reference, the following complete order code provides a detailed breakdown of a fully configured Prosonic Flow W 400 clamp-on ultrasonic flowmeter:

9W4BA0-AALHFNAABAAAACA2

This 9W4BA0 configuration represents a comprehensive specification suitable for a wide range of water, wastewater, and industrial process applications. The breakdown of each position in the order code is as follows:

This 9W4BA0-AALHFNAABAAAACA2 configuration is fully equipped with remote wall-mount transmitter housing, stainless steel sensor components, touch-control display, integrated web server, Heartbeat Technology diagnostics, factory calibration certification, and enhanced feature package including data logging.

For additional configuration options—including 9W4BA1 or 9W4BA2 variants with dual sensor sets, alternative approvals, specialized pipe material adaptations, or extended communication protocols—consult the Endress+Hauser product configuration tool Applicator or contact your local E+H sales representative.

Additional Reference Configuration: 9W4BA0-AALHFPAACAADACA2

A functionally equivalent alternative configuration within the same 9W4BA0 family is represented by the order code:

9W4BA0-AALHFPAACAADACA2

This configuration offers a similar feature set to the 9W4BA0-AALHFNAABAAAACA2 described above, with variations in optional feature selections and output configurations. Both configurations share the same core measurement capabilities, Heartbeat Technology, FlowDC functionality, and integrated web server access-16. The availability of multiple configuration codes demonstrates the modular flexibility of the Prosonic Flow W 400 series, allowing users to select the precise combination of features required for their specific application.

Complete Technical Specifications

Core Performance Parameters

Operating Conditions

Wetted Materials & Construction (Clamp-On System)

Transmitter Specifications

Outputs & Communication

Approvals & Certifications

Physical Specifications (Typical)

FlowDC Technology: Short Inlet Run Compensation

One of the most distinguishing technical features of the Prosonic Flow W 400 series is FlowDC (Flow Disturbance Compensation), Endress+Hauser‘s proprietary flow profile compensation algorithm integrated into the Proline 400 transmitter platform. Traditional flow measurement installations require significant straight pipe runs upstream and downstream of the measurement point—typically 5 to 10 pipe diameters—to establish a fully developed, symmetric flow profile. In real-world installations, space constraints, existing piping layouts, and the presence of elbows, valves, pumps, or reducers frequently make such ideal conditions impossible.

FlowDC technology addresses this challenge directly. When using two sensor sets (available on the 9W4BA2 configuration) or optimized single-path configurations, FlowDC compensates for disturbed flow profiles, maintaining the specified measurement accuracy with an inlet run of only 2 × DN (two pipe diameters). This capability transforms the 9W4B series into a practical solution for retrofits, tight-space installations, and applications where traditional straight-run requirements cannot be met-1-8.

The technical basis of FlowDC involves advanced signal processing algorithms that analyze the shape of the flow velocity profile using data from multiple acoustic paths (dual-path configurations) or from proprietary flow modeling (single-path optimized configurations). The transmitter continuously adjusts its calculation algorithms to compensate for profile asymmetries, delivering accurate flow measurement even under severely disturbed conditions.

For plant engineers facing space-constrained piping, short meter runs, or challenging flow conditions, the combination of the 9W4B series with FlowDC technology eliminates the need for costly pipe reconfiguration or extended straightening vanes.

Heartbeat Technology: Continuous Verification Without Process Interruption

The Proline Prosonic Flow W 400 series integrates Heartbeat Technology, Endress+Hauser‘s industry-leading diagnostic and verification platform. Unlike conventional flowmeters that require process shutdown, physical removal, or external reference devices to verify measurement integrity, Heartbeat Technology continuously monitors the entire measuring system in real time—without interrupting the measurement process-.

Heartbeat Technology Components:

Regulatory Compliance: Heartbeat Technology verification complies with ISO 9001:2015 Section 7.1.5.2 a (Measurement Traceability), providing auditable documentation that the flowmeter maintains measurement traceability to national standards without removal from service. For water utilities, wastewater treatment facilities, and industrial process plants operating under quality management systems, this feature significantly reduces compliance costs and verification intervals.

Practical Benefits:

No process shutdown required for verification

No external calibration equipment or third-party service providers needed

Auditable verification reports generated directly from the device

Early detection of sensor degradation or pipe wall changes

Predictive maintenance based on real diagnostic trends

For large water distribution networks where process interruption is impractical or economically prohibitive, Heartbeat Technology transforms the 9W4B from a passive measurement instrument into an actively verifiable, auditable component of the plant‘s quality assurance system.

Integrated Web Server & Remote Access

The Proline 400 transmitter platform provides native web server access, enabling full remote operation and configuration via standard web browsers. This feature eliminates the need for proprietary software, specialized communication adapters, or on-site visits for routine configuration changes and data retrieval.

Web Server Capabilities:

The integrated web server positions the 9W4B series for modern Industrial Internet of Things (IIoT) architectures, enabling centralized management of distributed flow measurement assets, remote troubleshooting, and data integration with plant SCADA systems, cloud platforms, or enterprise asset management systems.

Integrated Data Logger

Both the 9W4BA0, 9W4BA1, and 9W4BA2 variants include an integrated data logger capable of storing measured values, diagnostic events, and Heartbeat Technology verification records. The onboard memory capacity supports extended data retention for:

Long-term trend analysis of flow rates and consumption patterns

Historical verification records for regulatory compliance

Diagnostic event logging for root cause analysis

Data export via web server for external analysis

For applications requiring extended historical data retention or integration with external systems, the data logger provides a valuable onboard resource that operates independently of external SCADA or historian systems.

Key Benefits & Value Proposition

1. Noninvasive Installation – Zero Process Interruption

The clamp-on design of the Prosonic Flow W 400 series represents the ultimate in noninvasive flow measurement. The 9W4B sensors mount directly onto the exterior of existing pipes using strapping bands, requiring no pipe cutting, no welding, no process shutdown, and no production interruption. Installation can be completed in minutes rather than hours or days, with zero risk of leaks, contamination, or process release.

2. True Maintenance-Free Operation

With no moving parts and no wetted components, the 9W4B series eliminates mechanical wear, erosion, fouling, and obstruction issues. Special maintenance-free coupling pads ensure permanent acoustic coupling between sensors and pipe wall throughout the entire product life cycle. Once installed, the device operates continuously without scheduled maintenance, lubrication, seal replacement, or sensor cleaning-1.

3. Lowest Total Cost of Ownership for Large Pipes

The clamp-on design delivers exceptional cost-effectiveness that improves as pipe diameter increases. Unlike inline flowmeters where cost scales dramatically with pipe size—often making them economically impractical above DN 600—the 9W4B maintains a consistent cost profile across all diameters from DN 15 to DN 4000. For large water mains, transmission lines, and distribution networks, this translates into substantial capital cost savings-1.

4. Independent of Fluid Properties

The ultrasonic transit time measurement principle operates independently of fluid electrical conductivity, density, viscosity, pressure, and temperature. This makes the 9W4B series ideal for:

Variable-quality water sources (seasonal changes in turbidity or composition)

Wastewater streams with fluctuating characteristics

Applications where fluid properties change over time

Measurements requiring no recalibration when fluid properties change

Unlike electromagnetic flowmeters, which require minimum conductivity (typically ≥5 µS/cm), the ultrasonic method places no conductivity constraints on the measured liquid.

5. Bidirectional Measurement Capability

All 9W4B variants—9W4BA0, 9W4BA1, and 9W4BA2—support bidirectional flow measurement, accurately capturing flow in both forward and reverse directions with equal precision. This is essential for distribution networks with variable demand patterns, pump station recirculation loops, gravity-fed systems where flow direction may reverse, and applications requiring net flow calculation.

6. Flexible Pipe Material Compatibility

The 9W4B series provides reliable measurement on a wide range of pipe materials, including:

Carbon steel and stainless steel

Ductile iron and cast iron

Copper and brass

PVC, CPVC, and other plastics

GRP (Glass Reinforced Plastic) and FRP

Concrete and lined pipes (with appropriate acoustic adaptation)

Special sensor configurations are available for GRP and plastic pipes, ensuring optimal acoustic coupling and signal strength across all common pipe materials-2.

7. Safe Operation with Touch-Control Display

The 4-line backlit display with touch control enables full device operation—including configuration, diagnostics access, and verification initiation—without opening the transmitter enclosure. This maintains the IP66/IP67 environmental seal, eliminates exposure to internal electronics, and enhances operator safety in outdoor or harsh environments-2.

8. Full Remote Access & IIoT Readiness

The integrated web server and digital communication protocols (HART standard; Modbus RS485 optional) position the 9W4B series for modern Industrial Internet of Things architectures. Remote monitoring, configuration, diagnostics, and Heartbeat Verification reduce site visits, enable centralized management of distributed assets, and support integration with cloud platforms and enterprise systems.

Applications & Use Cases

Primary Application Fields

1. Water Distribution Networks

Municipal water supply mains (DN 15 to DN 4000)

Transmission pipelines between treatment plants and storage reservoirs

District metering areas (DMA) for leakage detection and water balance

Bulk water transfer and custody transfer applications

Fire protection water systems

2. Wastewater Treatment Facilities

Inlet and outlet flow monitoring

Inter-basin transfer measurement

Treated effluent discharge monitoring

Pump station flow verification

Combined sewer overflow (CSO) monitoring

3. Industrial Process Water

Cooling water systems in power generation, manufacturing, and chemical plants

Raw water intake for industrial facilities

Process water circulation loops

Demineralized water distribution

Plant utility water monitoring

4. Hydropower & Dam Operations

Turbine efficiency monitoring

Reservoir inflow/outflow measurement

Penstock flow verification

Environmental flow compliance

Fish passage and bypass flow monitoring

5. Irrigation & Agricultural Water

Large-diameter distribution mains

Canal and open-channel flow measurement (with appropriate mounting)

Pump station verification

6. Building & Facility Management

HVAC chilled water and hot water systems

Condenser water loops

Domestic water monitoring

Energy management and sub-metering

Why Choose Clamp-On Over Inline or Insertion?

The 9W4B clamp-on design provides the optimal balance of installation convenience, cost-effectiveness, and application flexibility, particularly for retrofit installations, temporary measurements, and applications where process interruption is unacceptable.

Installation & Commissioning Considerations

Clamp-On Installation Process

The Prosonic Flow W 400 is mounted externally to the pipe using strapping bands and coupling pads. The installation process is straightforward and requires no process interruption:

Pipe surface preparation – Clean the pipe surface at the sensor mounting location

Coupling pad application – Apply the maintenance-free coupling pads to the pipe surface

Sensor mounting – Secure sensors to the pipe using strapping bands

Cable connection – Connect sensor cables to the remote transmitter

Electrical connection – Apply appropriate AC or DC supply voltage

Configuration – Enter pipe diameter, wall thickness, pipe material, fluid type, and measurement units

Signal optimization – Adjust sensor positioning for optimal signal strength (guided by transmitter diagnostics)

Heartbeat Technology baseline – Perform initial verification to establish baseline performance

Operational verification – Confirm flow readings against expected values or reference

Recommended Installation Practices

Commissioning Workflow

Detailed installation, wiring, and commissioning instructions are provided in the official Endress+Hauser Proline Prosonic Flow W 400 Operating Instructions (document BA02086D/06/EN/02.24-00)-9. Additional resources include:

Technical Information TI01568DEN_0224-00 (4.1 MB) – Complete technical data-9

Operating Instructions BA02086DEN_0224-00 (6.5 MB) – HART communication version-9

Operating Instructions BA02302DEN_0124-00 (5.6 MB) – Modbus RS485 version-9

Device Parameter GP01167DEN_0224-00 (2.1 MB) – HART parameter documentation-9

Short Instruction KA01510DEN_0224-00 (2.7 MB) – Quick start guide-9

Access these resources directly from the Endress+Hauser website or through the Device Viewer tool using the serial number found on the device nameplate.

Comparison Summary: 9W4BA0 vs. 9W4BA1 vs. 9W4BA2

For rapid selection reference, the following comparison highlights the key differentiators among the three 9W4B series variants:

Selection Guidance:

Select 9W4BA0 for standard water and wastewater applications where cost-effectiveness is the primary driver and a single-path clamp-on measurement provides adequate measurement security.

Select 9W4BA1 for applications requiring the upgraded feature set of the Proline 400 platform with single-path measurement—ideal for industrial process water and general-purpose monitoring where enhanced diagnostics are desired but dual-path redundancy is not required.

Select 9W4BA2 for critical applications requiring redundant measurement paths, flow profile compensation via FlowDC, enhanced diagnostic capabilities, and the highest level of measurement reliability. This configuration is strongly recommended for regulatory compliance monitoring, custody transfer applications, and installations with challenging flow conditions (short inlet runs, disturbed flow profiles)-17.

Ordering Information & Configuration Codes

Example Order Codes

1. 9W4BA0 Standard Water Distribution Configuration

9W4BA0-AALHFNAABAAAACA2 – Reference configuration detailed above. Suitable for potable water mains, remote wall-mount transmitter, touch-control display, integrated web server, Heartbeat Technology, and enhanced feature package.

2. 9W4BA0 Alternative Water Configuration

9W4BA0-AALHFPAACAADACA2 – Functionally equivalent to the reference configuration with variations in optional feature selections-16.

3. 9W4BA1 Single-Path Upgraded Configuration

9W4BA1-AALHFNDACAAAAEA2 – Single sensor set with upgraded feature set, Heartbeat Technology, and enhanced diagnostics-14.

4. 9W4BA2 Dual-Path Premium Configuration

9W4BA2-C6LHGPDACFFBACA2AADCEB – Dual sensor sets (2 measurement paths), full FlowDC compensation, Heartbeat Technology, and extended diagnostics. This represents the premium configuration for critical applications requiring maximum reliability and flow profile compensation-14.

9W4BA2-C6LHGPDAEFABABA2AADCEB – Alternative dual-path premium configuration with extended options-14.

How to Configure Your 9W4B

Endress+Hauser provides the Applicator online tool for step-by-step product selection and ordering. Input your application parameters (pipe diameter, pipe material, fluid type, temperature range, required outputs, environmental conditions, desired measurement paths) and the tool generates the complete order code for your specific 9W4BA0, 9W4BA1, or 9W4BA2 configuration.

Alternatively, contact your local Endress+Hauser sales representative or authorized distributor with your application specifications to receive a configured quotation with complete order code.

Technical Documentation & Support Resources

Endress+Hauser provides comprehensive technical documentation for the Prosonic Flow W 400 series: