Intro to Inrush Current

Have you ever heard of an inrush current? Do you know why it is essential? The video gives an overview of how to measure inrush current and summarizes some of the features of an inrush surge mitigator.

Inrush current on a motor is also known as the starting current. It is the initial high input current needed to charge capacitors and transformers.

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Measuring the inrush current on a motor allows you to calibrate its transformers. Inrush current will increase as a motor age or needs its bearings greased.

To measure inrush current, you will need a clamp meter. Once the motor is connected to the meter, hit the inrush button on the meter, start the motor, and the reading will appear. You will need to look at the inrush current for 5 cycles. It will have settled out by then, so you can get an accurate reading. The inrush current will settle out quickly if you have a good motor. If you have a bad motor, it will take quite a long time. A large inrush current can lead to voltage dips and equipment failure, so it is important to monitor it continually. Now you know all about inrush current.