Product Overview

The Yaskawa GA50U4038ABA is a GA500 variable frequency drive for 380 to 480 VAC three-phase industrial motor systems. It provides a 25 HP or 18.5 kW Normal Duty rating with 38.0 A output current. For Heavy Duty applications, the applicable rating is 20 HP or 15 kW with 31.0 A output current.

This higher-current GA500 model is intended for larger industrial machinery where motor selection, power-system capacity, cabinet cooling and load duty must be evaluated together. The Normal Duty and Heavy Duty ratings represent different application limits and must not be mixed during selection.

Model-Specific Rating and Selection

The 38 A Normal Duty rating is typically relevant to moderate-overload applications such as centrifugal pumps and fans. The 31 A Heavy Duty rating should be used when the equipment requires higher starting torque, loaded acceleration or frequent speed changes.

A 25 HP motor should not automatically be connected based only on its power rating. Confirm motor full-load current, service factor, efficiency, base frequency and expected operating torque. For continuous high-load operation close to 38 A, additional current margin may be advisable.

Motor Control Technology

The GA500 platform supports V/f control and open-loop vector control for induction motors, together with compatible permanent-magnet motor operation. Open-loop vector control can provide improved low-speed torque and speed regulation without encoder feedback when motor parameters and autotuning are correct.

Commissioning data must come from the connected motor nameplate. Enter motor voltage, current, frequency, speed and power accurately. Evaluate shaft rotation and connected machinery before carrying out rotational autotuning.

Control, Safety and Communication

Programmable I/O allows integration of run commands, speed references, machine interlocks, fault signals and operating-status feedback. Embedded RS-485 supports MEMOBUS/Modbus RTU. Other industrial networks require compatible communication options and correct protocol configuration.

The GA500 Safe Torque Off circuit is rated SIL3 under IEC 62061 and PLe under ISO 13849-1 when incorporated into a validated safety system. STO disables torque production but does not provide electrical isolation.

Technical Specifications

Application Engineering

Applications include larger pumps, fans, conveyors, process machinery, industrial mixers and material-handling equipment. Review load inertia, breakaway torque, continuous current, minimum speed, acceleration time, stopping energy and mechanical speed limits.

The built-in braking transistor permits use of a correctly engineered external braking resistor. High-inertia equipment or frequent stopping can generate substantial heat, so resistor selection must include both peak energy and average duty.

Installation and Commissioning Notes

Install the IP20 drive in an enclosure with appropriate environmental protection and calculated heat dissipation. At this current level, verify supply capacity, upstream protection, conductor size, grounding, terminal torque and cabinet airflow. Follow applicable derating instructions for temperature, altitude, carrier frequency and mounting arrangement.

Before normal operation, test motor direction, speed limits, acceleration, deceleration, safety inputs, communication and protection response. Confirm the motor and machine remain within their electrical and mechanical limits.

Replacement Checklist

• Confirm GA50U4038ABA and its complete specification number.
• Select 38 A ND or 31 A HD operation correctly.
• Verify motor current and load-duty requirements.
• Check supply, conductor and protection capacity.
• Back up parameters and terminal functions.
• Verify STO, network and braking components.
• Inspect cooling fans and cabinet airflow.

Related GA500 Models

GA50U4031ABA provides 31 A Normal Duty and 24 A Heavy Duty output. GA50U4044ABA is the adjacent higher rating and should be considered when additional continuous-current capacity is required.

Inquiry and Supply Notes

Provide complete drive and motor nameplates, application duty, stopping requirements and communication protocol. Confirm external components, price and delivery time before ordering.