A new range of AC drives is available from EP Normand that will enable energy-efficient permanent-magnet motors to be used in a wide range of pump, fan and compressor applications.  Known as the AC650S Series, the new drives will eliminate the need to run permanent-magnet motors with closed-loop speed sensors, thus enabling them to be used as replacements for induction motors and thereby helping manufacturers to improve both performance and profitability.

By using the AC650S drives to switch from induction to permanent-magnet motors, energy consumption can be cut by up to 12% while at the same time reducing the combined drive and motor space requirement by as much as 75%.

Until recently, permanent-magnet motors have not been widely used in many industrial applications.  This is because they are in need of additional speed or position sensing mechanisms and is controlled by high-end drive units which make them relatively costly and complicated to install.  As a result of this, larger and less efficient induction motors have generally been the preferred choice.

By using innovative algorithm control based on motor voltage and current output, the new AC650S drives makes it possible for standard permanent-magnet motors to be used in closed-loop applications without the need for additional sensors.  Companies can therefore benefit from the energy savings that can be achieved from brushless motors, with savings of up to 12 per cent for a 0.75kW system being possible.

The new AC650S drives provide high start-up torque, without the need for additional tuning, and offer a range of features to make them quick and simple to setup and install.  Thus each drive is supplied with free software configuration tools, with pre-set macros for many common applications, and requires just a few motor parameters to be input during commissioning.  In addition, the AC650S has front panel-mounted LCD and input controls, with simple diagnostics, integrated EMC filters and analogue and digital I/O, including RS232 programming ports.  The new drive can also be supplied with optional Profibus-DP and Modbus RTU interfaces, while a cloning module is available to enable up to ten drive configurations to be stored for ease of maintenance.