Automation Technician Interview Questions and Answers

4-20 mA signal has a minimum value of 4 mA and a maximum value of 20 mA, while 0-20 mA signal ranges from 0 mA to 20 mA.

• 4-20 mA signal has a minimum value of 4 mA representing the lower limit of the signal range.

• 0-20 mA signal starts from 0 mA, allowing for a wider range of values compared to 4-20 mA signal.

• Both signals are commonly used in industrial automation for transmitting analog signals to control systems.

• 4-20 mA signal is often used for process control applications, w...read more

VFD stands for Variable Frequency Drive, which controls the speed of an AC motor by varying the frequency and voltage of the power supplied to it.

• VFD converts fixed frequency AC power to variable frequency and voltage output

• It allows for precise control of motor speed and torque

• VFDs are commonly used in industrial applications to save energy and improve process control