The VFD055E43A is a specific model of Delta inverter. The "VFD" stands for Variable Frequency Drive, which is a type of inverter used for controlling the speed of an electric motor. 

The "" in the model number refers to the power rating of the inverter, indicating that it is capable of driving motors up to 55 kilowatts. The "E" indicates that it is an economy-class drive, while the "43A" represents certain specifications of the drive such as voltage, current, and other features.

As an inverter, the VFD055E43A allows for precise control of motor speed and performance. It can handle various motor types and is commonly used in industrial applications for machinery, pumps, fans, and other equipment. It offers features such as adjustable frequency, torque control, and programmable input/output terminals.