SKB3400110 - Variable speed drive - CONTROL TECHNIQUES

Control Techniques SKB3400110 Frequency Drive - DIGIDRIVE SK

The frequency drive reference SKB3400110 is an inverter from the Digidrive SK range by Control Techniques (Nidec group), also marketed under the Leroy-Somer name in some territories. Designed for three-phase asynchronous motors, this unit provides industrial speed regulation with robust control logic and integrated protections. Its design includes two microprocessors, one of which is a DSP dedicated to pulse-width modulation (PWM), to optimise torque, stability and motor efficiency. The SKB3400110 addresses maintenance and replacement needs on installed fleets while offering quick commissioning through clear parameters and accessible I/O terminals. Typical applications include conveyors, pumping and ventilation, as well as special machines where a reliable V/f law, acceleration ramps and analogue setpoints ensure continuous production.

Technical specifications

• Manufacturer reference: SKB3400110
• Range: Digidrive SK
• Manufacturer: Control Techniques, distributed as Leroy-Somer depending on market
• Type: Variable speed drive for three-phase asynchronous motors
• Supply voltage: AC, exact values for SKB3400110 not provided in consulted sources; refer to the range documentation
• Power range: from a few hundred watts up to several kilowatts depending on frame size within the Digidrive SK range
• Rated output current: not specified for this reference; depends on the corresponding size
• Output voltage: variable three-phase generated by an IGBT inverter bridge via PWM
• Control mode: Open-loop V/f, other advanced modes available depending on range configuration
• Switching frequency: adjustable via parameters; value depends on configuration
• Control processor: DSP for motor control and a microcontroller for the interface and protections
• Built-in protections: overload, overcurrent, overvoltage, undervoltage, overheating, motor fault and thermal monitoring
• Inputs/outputs: digital and analogue I/O for start/stop, speed setpoint, plus relay outputs for signalling
• Cooling: fan cooling controlled according to load and temperature on applicable sizes
• Degree of protection: depends on size and mounting, typically IP20 for cabinet mounting

Overview of the DIGIDRIVE SK range

The Digidrive SK series is part of Control Techniques' AC drive offering widely used in industrial maintenance. Positioned for standard variable speed applications, it focuses on fast commissioning, broad compatibility with asynchronous motors and proven power electronics. Many sites still use it in original equipment or as replacements, particularly when migrating to newer families such as Commander C or Unidrive, making it a sought-after option for retrofits.

• Robust V/f control: reliable open-loop speed regulation, simple ramp settings, slip compensation and motor-data entry for adaptation to motor characteristics
• Practical integration: standard I/O terminals, optional communication according to range variants, and automatic protections that help ensure service continuity in industrial environments

The SKB3400110 fits this compatibility-and-simplicity approach, with a DSP platform that generates a PWM with adjustable carrier frequency to optimise the trade-off between motor noise, switching losses and control accuracy. This approach is suited to lines where stability and reliability are the priorities rather than vector control for highly dynamic applications.

Industrial applications

This Control Techniques drive is commonly used across manufacturing and utilities. Regulating three-phase asynchronous motors in conveying, pumping and ventilation is its primary field of application, with analogue setpoint configuration, acceleration ramps and integrated motor protection functions. It is also used on special machines and process automation where an accurate, repeatable V/Hz law is sufficient to maintain production quality.

• Material handling and intralogistics: belt conveyors, powered rollers, lifts
• HVAC and utilities: fans, extractors, circulators, centrifugal pumps
• Packaging and labeling: drive rollers, dosing systems, speed-controlled labelers
• Food processing and continuous processes: preparation lines, crate conveyors, transfers
• Special machines: auxiliary drives that do not require vector control

Integration and communication

The SKB3400110 is configured via the range keypad with direct access to essential parameters, simplifying commissioning and maintenance. The analogue inputs accept common speed setpoints, while the digital inputs control start, stop and profile selections. Relay outputs are provided for status and alarm signalling, easing interfacing with an existing programmable logic controller.

Depending on Digidrive SK variants and available options, integration with industrial fieldbuses can be achieved via dedicated communication cards, or through serial interfaces and I/O for straightforward coupling with a line PLC. This flexibility enables progressive modernisation of installations while maintaining compatibility with the existing automation architecture.

Availability and warranty

The Control Techniques SKB3400110 frequency drive is offered by Standard Exchange Industry as a replacement supply, exchange unit or repair, with each unit bench-tested prior to shipment. Dispatch is arranged within 24 to 72 hours to over 120 countries. Our technical teams support you to identify the correct Digidrive SK reference and validate electrical and mechanical compatibility with your motor and cabinet. A warranty covers the service provided, and integration support is available to secure restart and minimise downtime.