IP54 frequency inverter benefits from WEG Optimal Flux technology

Paul Boughton

WEG is extending the application range of its CFW-11 variable-frequency inverter, with an IP54 variant. Integrating all of the innovative features of the standard CFW-11, the IP54 version offers extended scope for operation in harsh environments such as in the food and beverage industry, providing protection against the ingress of dust and splashing water.

In addition to providing safeguards for inverter control operations in tough applications, the IP54- rated CFW-11 offers users the benefits of WEG's patented Optimal Flux technology. This minimises the losses of totally enclosed fan-cooled (TEFC) induction motors used with constant- and variable-torque loads, especially at low speeds where motor ventilation is inefficient. Optimal Flux overcomes the problem of reduced torque under these operating conditions, as well as the costs of traditional alternatives - such as motor oversizing and additional ventilation.

In addit6ion to delivering optimised control of motors, even at low speeds, the CFW-11 IP54 provides users with an easy-to-use, universal drive platform. It offers plug-and-play technology that is automatically configured, enabling the inverter to suit a wide range of drive applications: standalone, centralised, and decentralised with networks. This flexibility provides a wealth of integration possibilities, lowering total system costs whilst improving productivity. Furthermore, it enables users to standardise on one product for all types of VFD control, with the commensurate benefits of savings on equipment costs, inventory, training and maintenance requirements.

What makes the CFW11 so configurable is the number of features that combine to produce an overall systems platform. Principle among these are plug-and play technology, which automatically recognises and configures accessories and option cards used for customisation, enabling easy installation while eliminating the costs and time associated with manual configuration.

Thanks to Universal Drive Selection, the CFW11 IP54 can perform in V/f, VVW voltage vector, sensorless vector and vector encoder modes. Onboard systems modules tailor the drive both in terms of scalable control, (ie replacing a PLC) and in terms of communications, with one of the widest choices of fieldbus options (including Ethernet IP) available from any drive system. A further choice of normal and heavy-duty ratings allows the drive to be adapted optimally to all types of load. A full-function, onboard HMI with backlit graphic display and soft keys facilitate inverter programming and monitoring, and built-in DC link inductors enable compliance with IEC 61000-3-12 regarding harmonics; they also enable the use of cables up to 100m long, without the requirement for external line reactors.

The facility to customise the CFW-11 IP54 and achieve scalable control systems tailored to OEM needs is realised with a total of 14 options cards: I/O (digital and analogue 14 bit A/Ds and D/As), PLC, encoder and communications. These simply clip into five slots on the CFW-11 IP54 and are automatically recognised and configured, thereby eliminating the need for manual input. At any time up to four of these modules can be used. The PLC-11 options card suits applications where the frequency inverter on its own cannot provide the required level of control or interfacing. By removing the requirement for a separate PLC, it provides OEMs and users with substantial reductions in equipment, enclosure and installation costs. Simply by installing a PLC-11 option card into the drive, users can perform general digital and analogue I/O control tasks, or to employ functions such as positioning with trapezoidal and S profiles (absolute and relative), master/slave synchronisation between two or more motors, or an electronic gearbox.

In addition, the CFW-11 IP54 also offers the options of: a safety stop feature, in accordance with EN 954-1 category 3; an RFI filter in compliance with EN 61800-3 (internal); and the facility for an external 24V DC control feed.

For more information, visit www.weg.net

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