Excella Electronics manufactures AC Variable Frequency Drive is available in 4 models viz. VF - NC1, VF - S11, VF - PS1 and VF - AS1; is used in ventilation systems for large buildings, on pumps, elevator, conveyor and machine tool drives. Excella Electronics is an ISO9001:2008 and CE certified company. Excella Electronics also supplies products like Power Supplies, Tachogenerators, Shaft Couplings, Static Eliminators, Stepper Motors, Electronic instruments, Stepper Motor and controller, encoders and Gear Boxes. AC Variable Frequency Drive is a device for controlling the rotational speed of an alternating current [AC] electric motor by controlling the frequency of the electrical power supplied to the motor. The AC Variable Frequency Drive is easy to wire and install, easy to select as per the application and easy to set up and operate.