Hitachi WJ200N-004HFC Inverter Small Size Big Performance for Small-Scale Automation

Hitachi WJ200N-004HFC Inverter

The Hitachi WJ200N-004HFC represents the compact entry point into the robust WJ200N series of variable frequency drives, delivering sophisticated motor control capabilities in a remarkably small footprint. Designed for applications requiring precise speed regulation of three-phase AC induction motors up to 0.4 kW (0.5 HP) in constant torque mode (0.75 kW / 1 HP in variable torque mode), this drive combines advanced technology with user-friendly operation. It is an ideal solution for a vast array of small-scale automation tasks, from packaging machinery and conveyor sections to laboratory equipment and small pump/fan systems, where space is at a premium and efficiency is critical.

Core Strengths and Technological Differentiation

Precision Control in a Compact Design

Despite its small size, the WJ200N-004HFC does not compromise on performance. It incorporates the same advanced control algorithms found in larger models within the series.

• High-Performance Sensorless Vector Control (SLV): This technology enables the drive to generate high starting torque (200% at 0.5 Hz), ensuring reliable startup for applications with high initial friction or inertia, all without the cost and complexity of a feedback encoder.

• Adaptive Control Strategies: The inverter offers multiple control modes, including standard V/F for constant torque applications (e.g., conveyors) and a reduced torque (quadratic) V/F curve optimized for centrifugal pumps and fans, which significantly improves energy efficiency in these applications.

• Auto-Tuning Functionality: The drive can automatically measure key motor parameters at standstill, optimizing its control output for the specific connected motor. This simplifies commissioning and enhances operational stability and torque accuracy.

Energy Efficiency and Dynamic Response

• Intelligent Energy Saving Mode: The inverter continuously monitors the motor load. Under light-load conditions, it automatically reduces the output voltage to minimize wasteful magnetizing currents, leading to substantial energy savings without sacrificing performance.

• Configurable Braking Performance: While the base unit includes DC injection braking, it is fully compatible with an optional external braking resistor. This allows for controlled, rapid deceleration of high-inertia loads, increasing machine throughput and cycle times.

Unmatched Ease of Use and Integration

• The user interface is centered around a detachable, intuitive digital keypad with a bright 4-digit LED display. It allows for straightforward parameter configuration and provides clear visibility of operational data like output frequency, current, and fault status.

• Flexible Command Sources: The drive accepts speed commands from multiple sources: the keypad's potentiometer, external analog signals (0-10 V or 4-20 mA), digital terminals for up to 16 pre-set speeds, or directly from a supervisory system via the built-in communication port.

• Integrated PID Controller: A built-in Proportional-Integral-Derivative (PID) controller allows for direct closed-loop control of process variables such as pressure, flow, or level, eliminating the need for and cost of an external process controller.

Comprehensive Protection for Enhanced Reliability

• The drive is equipped with a full suite of protective features to ensure longevity and prevent damage. These include electronic thermal overload protection for the motor, instant overcurrent and overvoltage protection, undervoltage detection, and ground fault protection.

• Safety Integration Ready: The programmable digital inputs can be configured to implement safety functions such as an emergency stop or a Safe Torque Off (STO) compliant function when used in conjunction with an external safety relay, helping the end machine meet necessary safety standards.

• Robust Design: The self-cooling (fanless) design for this power rating enhances reliability by eliminating a common point of failure and reduces audible noise, making it suitable for quiet environments.

Seamless Connectivity for Modern Automation

• Built-in Modbus RTU: Standard RS-485 communication via the Modbus RTU protocol enables effortless integration into a wide range of control architectures, from small PLCs to large-scale building management or SCADA systems.

• Expansive I/O Capabilities: The drive features multiple programmable digital and analog inputs/outputs, providing the necessary flexibility to interface with sensors, push-buttons, and indicator lights, facilitating a cohesive and intelligent control system.

Technical Specifications

Target Applications

The WJ200N-004HFC excels in a wide range of compact and low-power applications, including:

• Small Conveyors and Sorting Systems: Providing smooth acceleration and deceleration in material handling applications.

• Laboratory and Analytical Equipment: Precisely controlling mixer speeds, pump flows, or spindle rotations in sensitive environments.

• Small Pumps and Fans: Optimizing energy use in compact HVAC units, ventilation systems, or liquid transfer applications.

• Packaging Machinery: Controlling individual axes like sealers, feeders, or cutters with high precision.

• Light-Duty Machine Tools: Driving spindles or feeds in small drilling, milling, or grinding machines.

Programming and Customization

The inverter's parameter structure is logically organized, making setup and customization efficient. Key programmable features include:

• Terminal Function Assignment: Each digital input and output can be assigned a specific function from a comprehensive list, tailoring the drive's behavior to the exact needs of the machine.

• Multi-Speed Operation: Up to 16 different speeds can be pre-programmed and selected via digital input combinations, enabling complex motion sequences.

• Advanced Motor Protection: The electronic thermal protection feature can be finely tuned to match the specific full-load current rating of the motor, providing optimal protection.

Safety and Conformity

The WJ200N-004HFC is engineered to meet rigorous international standards, ensuring safety and quality:

• CE Marked (Conforms to EU EMC and Low Voltage Directives)

• cULus Listed (UL 508C)

• RoHS Compliant

Conclusion

The Hitachi WJ200N-004HFC is a testament to the principle that advanced motor control technology need not be bulky or complex. It packs the performance, efficiency, and intelligence of larger drives into a compact, reliable, and easy-to-use package. For OEMs, system integrators, and end-users seeking a cost-effective and highly capable solution for small motor control applications, the WJ200N-004HFC offers an unparalleled combination of precision, protection, and integration ease, ensuring optimal performance and reliability in a demanding world.