SK4,5T - Variable speed drive - LEROY SOMER

LEROY SOMER SK4,5T Variable Speed Drive - AC Family

The reference variable speed drive SK4,5T is a drive unit in the AC family from LEROY SOMER. Designed to control three-phase asynchronous motors by frequency variation, it is aimed at maintenance departments, system integrators and OEMs looking for a reliable solution for speed control and energy optimization of driven equipment. This model integrates into existing automation architectures and meets the common requirements of continuous production lines, plant utilities and special machines. Its design promotes structured commissioning, stable operation and predictable maintenance to limit unplanned downtime and safeguard operational availability. For modernization projects or like-for-like replacements, it is a relevant reference when functional compatibility, longevity of interfaces and process continuity are priorities.

Technical specifications

• Manufacturer reference : SK4,5T
• Range : AC drive family from the manufacturer, suitable for controlling asynchronous motors
• Manufacturer : LEROY SOMER
• Type : Frequency drive for three-phase asynchronous motor, speed control by frequency modulation
• Supply voltage : according to the reference configuration and the site network, details to be confirmed on the nameplate
• Rated power : depends on the version associated with SK4,5T, to be validated via technical documentation or on-site measurement
• Rated output current : value depends on motor sizing and variant, to be confirmed
• Output voltage : three-phase AC motor supply with PWM control, range depending on supply and settings
• Control mode : V/f or sensorless vector depending on series configuration and available options
• Control interfaces : common digital and analog I/Os, local terminal strip, PLC compatibility depending on wiring
• Communication : fieldbus options available via communication cards, to be selected according to the architecture
• Degree of protection : varies depending on version and panel integration environment, check the exact reference

Product range overview

LEROY SOMER AC variable speed drives are widely deployed in industrial installations to provide precise speed control, limit inrush current and adapt torque to load conditions. Their broad use across process equipment and utilities simplifies maintenance, parts availability and the reuse of parameter templates across multiple machines in the fleet. The range philosophy focuses on consistent configuration menus, compatibility with standard automation signals and ease of on-site replacement to reduce downtime during corrective interventions.

• General variable speed usage : control of conveyors, fans, pumps and mixers with speed laws adapted to the application
• High-dynamics applications : ramp functions, current limitation and acceleration configuration to protect mechanical components and the motor

The SK4,5T model fits this standardization approach, which facilitates reusing existing parameters during a standard exchange and reduces the risk of errors at restart. It is therefore relevant for sites seeking operational continuity without redesigning their automation architectures.

Industrial applications

The SK4,5T drive is suitable for many environments, both for new installations and for corrective or preventive maintenance. It meets needs for speed control, reduction of mechanical stress and improved energy efficiency on AC drives.

• Conveying and intralogistics : fine-tuning belt speeds, soft starts, synchronization via PLC
• Pumping and fluid handling : speed laws to maintain flow or pressure, reduction of water hammer
• Ventilation and industrial HVAC : adapting speed to real needs to limit consumption
• Mixing, extrusion, dosing : controlled ramps to preserve kinematics and process quality
• Material handling and packaging : stable control of auxiliary drive axes with status feedback to the PLC
• Food and chemical industries : adapting throughputs according to recipes and process constraints

Integration and communication

The SK4,5T integrates into an automation architecture via standard signals or optional fieldbuses depending on the version. Typical integration schemes include Start, Stop, direction, preselected speeds via I/Os, an analog speed reference, as well as relay status feedback. Optional cards can provide fieldbuses such as Modbus RTU, CANopen, PROFIBUS-DP or equivalents, depending on the chosen configuration and availability on the reference, which simplifies parameter exchange and integration with a PLC or existing numerical control. Commissioning follows a methodical approach including motor identification, verification of rotation direction, setting ramps and current limits, then functional validation by no-load and loaded tests.

From a reliability standpoint, attention is given to EMC compliance, use of filters and chokes if required, upstream protection by appropriate circuit breakers or fuses, and brake resistor management if the application demands it. Common local supervision functions via display, parameter set backup and restore, and the ability to duplicate a configuration from one unit to another help reduce maintenance intervention time. Daily operation benefits from alerts and standardized fault codes, easing diagnosis and return to service.

Availability and warranty

Standard Exchange Industry offers the LEROY SOMER SK4,5T for supply, standard exchange or repair depending on the condition of your installation. Each unit supplied is bench-tested according to a functional test protocol, then shipped within 24 to 72 hours depending on stock and destination. Services come with a warranty ranging from 6 to 24 months depending on the selected service. In the event of a line stoppage or obsolescence, our technical team supports you to confirm reference compatibility, define the critical parameters to recover and secure the return to production as quickly as possible.