Lenze's new MCA and MQA asynchronous servo motors are claimed to deliver more power than comparable motors as a result of a revised cooling concept. A common mechanical design with three different forced ventilation options can deliver up to 200 per cent more power at a given inertia. Combined with other state-of-the-art features such as insulated bearings and electronic nameplates, this makes the MCA and MQA motors a good choice for economy and long life.
MCA and MQA motors are available with rated torques up to 125Nm and a large reserve for peak torques up to 500Nm. The high power density is a result of the forced ventilation design. At the lowest level are IP54 motors with conventional external forced cooling. An increase of about 10 per cent is achieved (at the expense of reduced protection to IP23) by means of a radial blower that forces air through internal channels in the motor. A further increase of about 25 per cent is available through a larger blower mounted radially.
High power and high torque with low inertia
In fact all three versions deliver high powers and torques for their size, but the radially blown models are exceptional in combining high power and high torque with low inertia. Compared to other motors of a similar inertia, these motors are said to deliver two to three times more power. There is a space saving too; these motors give 20 to 30 per cent more power for a given volume. The result is better dynamics on high-speed machinery from the increased ability to inertia match together with savings in cost and space.
The versatile MCA and MQA motors come with a wide range of features. Insulated bearings increase motor life because they prevent electro-erosion damage incurred by hazardous bearing currents – which results from the high switching frequency of servo drives. Also standard is a choice between resolvers, incremental and absolute encoders. Each motor can accept a choice of two sizes of spring-applied brakes for emergency stop and holding duties. An electronic nameplate built into the feedback connector allows exact matching to Lenze drives and optimum performance. The connectors themselves are available in new SpeedTec design that reduces machine build time.
Lenze summarises by saying that these asynchronous servo motors deliver market-leading performance in a package that is compact and economical. They are suitable for use with Lenze ECS, 9300 and 9400 servo drives for powers up to 38kW.