Product Overview
The Emerson SP4403 is a high-performance AC variable speed drive from the Unidrive SP series, designed to control the speed and torque of three-phase AC induction motors. It provides a reliable and efficient means of matching motor output to changing process demands in industrial applications. By adjusting motor speed instead of using mechanical throttling or flow-restriction methods, the drive helps reduce energy consumption and mechanical wear while improving process control.
The SP4403 is a size 3 Unidrive SP drive with a 45 kW / 60 HP rating and a 480 VAC, 60 A input and output capability. It supports open-loop vector control for standard three-phase induction motors, making it suitable for applications that require good speed regulation without the added cost and complexity of a feedback encoder. Its 150% overload capacity provides additional torque for short-duration demands commonly encountered during starting or load changes.
The Emerson SP4403 uses an integrated SMARTCARD for parameter storage, drive backup, and rapid commissioning. This feature allows configuration to be copied between drives, reducing setup time during installation or replacement. The drive also includes standard analog and digital I/O, a serial communications interface, and expansion capability through optional plug-in modules. This flexible architecture allows the SP4403 to adapt to a range of machine and process automation requirements.
Designed for demanding industrial environments, the drive incorporates robust protection features including overcurrent, overvoltage, undervoltage, earth fault, and motor overload monitoring. Its open-loop vector control, flexible I/O, and parameter management make it suitable for pump, fan, conveyor, compressor, mixer, and material handling applications. Although the Unidrive SP series has been superseded by newer Control Techniques and Emerson drive platforms, the SP4403 remains a widely used installed-base product and an important spare-part requirement for many facilities.
Technical Specifications
| Parameter Name | Parameter Value |
|---|---|
| Product Model | Emerson SP4403 |
| Product Series | Unidrive SP |
| Manufacturer | Emerson Industrial Automation / Control Techniques |
| Product Type | AC Variable Speed Drive / Inverter |
| Frame Size | 3 |
| Rated Power | 45 kW / 60 HP |
| Input Voltage | 380–480 VAC, 3-phase |
| Input Current | 60 A |
| Output Voltage | 0–480 VAC, 3-phase |
| Output Current | 60 A |
| Control Method | Open-loop vector control |
| Overload Capacity | 150% |
| Standard I/O | 5 digital inputs, 2 analog inputs, 2 analog outputs, 3 relay outputs |
| Communications | Serial communication interface; optional fieldbus modules |
| Parameter Storage | Integrated SMARTCARD |
| Operating Temperature | 0…40 °C, derating above 40 °C |
| Storage Temperature | -40…+70 °C |
| Protection Rating | IP20 |
| Dimensions (H × W × D) | 391 × 200 × 192 mm |
| Weight | 8 kg |
Main Features and Advantages
The primary advantage of the is its combination of power, control performance, and flexible configuration. With a 45 kW / 60 HP rating and 60 A output capacity, the drive can control medium-power three-phase motors across a wide range of industrial applications. Open-loop vector control provides good speed regulation and torque performance without requiring a motor feedback device in many installations.
Energy efficiency is another significant benefit. By varying motor speed to match process demand, the can reduce the energy used by pumps, fans, conveyors, compressors, and similar equipment. The drive also helps minimize mechanical stress by providing controlled acceleration and deceleration. This can extend the service life of motors, couplings, gearboxes, belts, and connected machinery.
The integrated SMARTCARD enhances commissioning and maintenance efficiency. The uses the removable card to store drive parameters and configuration data. During replacement, the SMARTCARD can simplify restoration of the original setup, helping reduce downtime. It also allows configuration templates to be transferred between drives in multi-motor installations.
Flexible connectivity supports integration with industrial control systems. The drive provides standard analog and digital I/O, three relay outputs, and a serial communication interface. Optional expansion modules allow the to support additional I/O and industrial communication protocols. This makes it adaptable to both standalone machine control and integrated automation systems.
Comprehensive protection is built into the drive. Overcurrent, overvoltage, undervoltage, earth fault, and motor overload monitoring help protect the motor and drive from abnormal operating conditions. The also includes a keypad interface for local monitoring, commissioning, and adjustment. These features make it easier for maintenance personnel to diagnose problems and restore normal operation.