Decentralised low-power variable speed drives

“The compactness and flexibility of the MW500 variable speed drives allow users to install them exactly where they are needed”, explains Johannes Schwenger, Head of Product Management Low and Medium Voltage Drive Systems Europe at WEG.  “The new frame size extends our successful drive product line with a flexible and durable solution for low power levels.”

The MW500 supports both voltage vector control (VVW) and V/f characteristic curve control and offers a robust and durable solution. The vsd can handle high overload of 150% for 60 seconds every 10 minutes and can be deployed at ambient temperatures up to 40°C (wall mounting) or 50°C (motor mounting).

Sturdy design for diverse applications
A sturdy housing design with protection rating IP66 or NEMA 4X allows the variable speed drives to be mounted directly on the motor terminal box or on the wall using an adapter plate. This eliminates the need for a motor feed cable and switch cabinet, reducing complexity and costs for installation and commissioning. This allows users to install the MW500 close to the controlled motor, increasing deployment flexibility. Designed for decentralised installation, the variable speed drive can be used for a wide range of applications, including centrifugal pumps, compressors, pumps in the process industry, fans and blowers, mixers and filling machines, washing machines and dryers, conveyors, and general mechanical engineering.

Designed for decentralised installation, MW500 variable speed drives are now available for operating induction motors with low power in the range of 370 to 550 W. This means the MW500 series is available for the range of 370 W to 7.5 kW with mains voltage 280 to 480 V in three frame sizes (A, B and C), and for 370 W to 1.5 kW with 200 to 240 V in one frame size (A).

Extensive configuration options and easy operation
The standard version of the MW500 comes with a PID process controller and an integrated PLC with numerous programming functions. The device includes an EMC filter compliant with EN 61800-3. Versions for categories C2 and C3 are optionally available. An analogue speed control potentiometer is also included in the drive to enable setting the speed of an induction motor without the need for a control panel. If desired, users can operate the device easily and intuitively using an optional integrated control panel (HMI), which is available in a version with remote control. Three LEDs on top of the drive indicate the Ready, Alarm and Fault states. An optional mains disconnect switch can also be installed for easy and safe maintenance. A special coating (IEC 60721-3-3, category 3C2) protects the electronics boards of the MW500 against dust, humidity and chemicals. The drive is cUL and CE certified.
To ensure maximum flexibility, digital I/O and communication protocols such as CANopen, DeviceNet and Profibus DP are available for the MW500 as optional extension modules. The Windows-based SuperdriveG2 application software for programming, control and monitoring of the MW500 is available to customers on the WEG website as a free download.

Modular design
The decentralised drive is based on the same successful device platform as the CFW500 variable speed drive, which features a modular design and offers similar optional accessory modules. The MW500 can also automatically recognise and activate the accessory modules, which are designed as convenient plug-and-play units. The available extension modules include analogue and digital I/O as well as USB, RS485 and RS232 interfaces. A mobile memory card (Mcard) additionally allows convenient transfer of process data from one device to another. The extension modules and compatibility with the CFW series of variable speed drives (CFW500, CFW700 and CFW11) allow a wide variety of applications to be covered by a single device. This enables users to reduce stocks, saving both space and costs in stockkeeping.