Speed indicator and current indicator devices are two types of instruments that are commonly used in conjunction with Variable Frequency Drives (VFDs) to measure and monitor the performance of electric motors.

A speed indicator, as the name suggests, is a device that measures the rotational speed of an electric motor that is being controlled by a VFD. It can be a physical device such as a tachometer that is attached to the motor shaft or an electronic device that measures the motor's frequency and calculates the speed. The speed indicator provides real-time feedback on the motor's speed, allowing operators to adjust the VFD settings as needed to maintain the desired speed.

A current indicator, on the other hand, is a device that measures the electrical current flowing through the motor while it is running. It can be a physical device such as an ammeter or an electronic device that measures the motor's current using sensors. By monitoring the motor's current, the current indicator provides information on how much power the motor is consuming, allowing operators to adjust the VFD settings to optimize energy efficiency and prevent damage to the motor due to overloading or overheating.

Both speed and current indicators are important tools for monitoring and controlling the performance of electric motors that are being controlled by VFDs, helping to ensure efficient and safe operation.