SK5,5T - Variable speed drive - LEROY SOMER

LEROY SOMER SK5,5T frequency converter - Commander SK

The frequency converter SK5,5T belongs to the Commander SK series distributed by LEROY SOMER for controlling three-phase asynchronous motors. Designed for demanding production environments, it meets the needs of maintenance teams, integrators and engineering departments facing machine uptime and energy optimization requirements. In retrofit as well as in new installations, the Commander SK range provides a reliable platform for speed variation, torque adjustment and motor protection, with methodical commissioning and stable operation. The SK5,5T is positioned as a suitable solution for conveyors, pumps, fans and general drive assemblies, where speed consistency and control quality directly impact process performance. The reference coding guides sizing and must be checked on the nameplate to validate supply, power and installed options.

Technical characteristics

• Manufacturer reference : SK5,5T
• Range : Commander SK
• Manufacturer : LEROY SOMER
• Type : Variable speed drive for three-phase asynchronous motors
• Supply voltage : depending on series version, typically 200-240 V AC or 380-480 V AC, 50/60 Hz
• Rated power : the SK5,5T designation is generally associated with ~5,5 kW, to be confirmed on the nameplate and installation documentation
• Nominal output current : depends on chassis, thermal setting and ventilation conditions
• Output voltage : 0 to supply voltage, three-phase, PWM modulation
• Control mode : V/f and sensorless vector control, depending on software configuration and options
• Protection functions : overvoltage, overcurrent, overheating, under/overvoltage protections, dependent on parameter settings
• Degree of protection : typically IP20 for cabinet mounting, to be confirmed by version

Overview of the Commander SK range

The Commander SK series targets ease of implementation and operational stability, with a clear parameter philosophy and functional blocks dedicated to common speed variation applications. It is suited to scalable automation architectures, operating locally via terminal block inputs/outputs, or integrated with a automate programmable through optional communication cards. Units in the series are sized for industrial cabinet wiring, with mounting accessories, EMC filters and, depending on variants, braking resistor components. The control logic provides acceleration and deceleration ramps, torque limits, thermal monitoring and controlled stop functions in line with good motor control practice. This range is widely deployed in installations where operational continuity and maintainability are priorities, which facilitates identical replacement or interchangeability within a managed obsolescence strategy. To ensure compatibility, verification of board references, firmware and I/O options is recommended during a standard exchange or repair.

Industrial applications

The SK5,5T drive integrates into processes where speed and torque regulation determine quality and efficiency. It is intended for continuous production lines and standalone stations requiring precise control of accelerations and setpoints. The following examples illustrate typical use cases, subject to power and supply compatibility with the installed motor :

• Conveying and handling : speed adjustment, section synchronization, soft starts to limit mechanical stress
• Pumping and fluid processing : flow and pressure adaptation, reduction of hydraulic shocks and energy optimization
• Industrial ventilation and HVAC : control of fans and extractors, fine adjustment of airflow according to process needs
• Food & packaging : drive of rollers, dosing and bagging machines, with parameterised acceleration profiles
• Assembly machines : control of auxiliary motors, simple positioning via sensorless vector control
• Textile and paper : regulation of drive sections with web tension constraints
• Intralogistics : control of sorting systems, transfers and lifts, integration with supervision

Integration and communication

The Commander SK connects via terminal block to logic and analogue inputs for local control by potentiometer, 0-10 V or 4-20 mA setpoint, and run/stop, direction, fault and preset signals. Integration into automation architectures is possible via optional fieldbus interface cards such as Modbus RTU, PROFIBUS-DP, DeviceNet or CANopen, depending on the installed card and hardware version. This connectivity facilitates networking drives with a automate programmable and a commande numérique, feedback of statuses to a supervision system and real-time parameter adjustment. Configuration follows a structured approach, with selection of V/f or vector control type, motor identification, ramps, current limits and fault management. Common application profiles, such as pumps and fans, can be reproduced using parameter templates, speeding up restart after maintenance. In case of replacement, recording existing parameters and controlled duplication of settings ensure identical motor behaviour while respecting the installation's thermal and EMC constraints.

Availability and warranty

The LEROY SOMER SK5,5T frequency converter is offered as reconditioned supply or as a standard exchange, tested on bench according to documented procedures. Standard Exchange Industry ensures shipment within 24 to 72 hours to over 120 countries and provides a warranty adapted to the chosen service. Our technical team supports you to validate power, voltage and communication option compatibility, and to define the best approach between replacement, supply or repair. In the event of a line stop, rapid analysis of the nameplate, wiring diagram and existing parameters helps define the scope of intervention and secure the return to service. For any migration or retrofit, we recommend evaluating mechanical loads, cabinet ventilation and EMC requirements to ensure long-term compliance and stability of motor control.