Variable frequency drives provide infinitely variable speed control. Typically, they are used to control AC fans or pumps in HVAC applications. These frequency inverters can control various motor types: single phase AC motors, IE2, IE3 and IE4 induction motors, AC permanent magnet motors, brushless DC motors, synchronous reluctance motors, etc. They use IGBT technology to vary both motor voltage and frequency via pulse width modulation. This results in a very precise and efficient motor control. Thanks to the integrated macros, configuration remains easy. Pump mode makes energy efficient pump control possible. Fan mode (incl. fire operation) makes air handling a breeze, ideal for simple HVAC systems.