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Imagine standing in front of a brand-new high-voltage switchgear panel. Millions of dollars of equipment sits right behind those heavy steel doors. Your team is ready to energize the facility, and everybody is watching. You put your hand on the main breaker. Do you flip it and just hope for the best?

Excitation current testing can help detect winding faults such as turn-to-turn shorts, open circuits, and grounded windings.

To understand excitation current testing, it helps to start with magnetism. Every magnet has a magnetic field made up of lines of force. These magnetic lines leave the north pole and enter the south pole. The total number of magnetic field lines is called magnetic flux.

When a power or distribution transformer is disconnected from the power system, the transformer core may not return to a completely unmagnetized state. Some magnetic flux can remain in the core. This is called remnant magnetism or residual magnetism.

What does the future hold for our industry — especially when it comes to those all-important standards that ensure reliability, protect property, and help us to avoid injury or death? As we revise and update codes and standards from NETA, NFPA, IEEE, ASTM, NEMA, CSA, and OSHA, I think we should all read this very carefully, especially the summary.