What information does the (MM) designation on an electric meter badge indicate?

The (MM) designation on an electric meter badge signifies the number of wires and the form designation of the meter. This information is essential for understanding how the meter is designed to connect to the electrical system and how it measures the current flowing through the wires.

In practical terms, the number of wires indicates whether the meter is for a single-phase or three-phase system, which affects both the installation and the accuracy of the meter readings. The form designation provides additional details about the specific configuration and capacity of the meter. Understanding the (MM) designation helps utility workers and engineers ensure that the correct meter is used for a given application, promoting efficient and accurate energy measurement.

The other choices address different aspects of the meter but do not pertain to the specific information conveyed by the (MM) designation. The meter manufacturer pertains to the brand or company that produced the meter, the watthour meter constant is related to the calibration and measuring capability of the meter, and the frequency rating indicates the operational frequency but does not link to the wiring or form designation.