Today, we’d like to discuss how you can perform a comprehensive measurement using Electrical Signature Analysis (ESA) for your motor analysis. This technique allows us to gather crucial insights by measuring both the three-phase current and voltages.

To measure the current accurately, you have several options e.g. current transformers, current clamps, or Rogowski coils. For low-voltage measurement, direct measurement using shunt resistors is a reliable choice. Remember to ensure that your data acquisition system has a sufficiently high bandwidth and dynamic range to capture accurate readings.

From a connection standpoint, there are two approaches to consider: measuring in the motor terminal box or in the motor control cabinet. While measuring in the terminal box provides greater accuracy, the latter, measuring in the control cabinet, is considered safer and therefore preferable. The schematic representation on the right illustrates how this connection can be established.