Tom Bishop, PE
EASA Senior Technical Support Specialist
On January 9, 2026, NEMA announced that MG 00001-2024, Motors and Generators, Table 12-23 had been revised. The new title of Table 12-23 is “Full-Load Efficiencies of 60 Hz Premium 4 Efficient Polyphase Electric Motors Rated 600 V or Less.” In the original edition of MG 00001-2024, Table 12-23 was titled “Full-Load Efficiencies of 60 Hz Super Premium Efficient Polyphase Electric Motors Rated 600 V or Less.” Note that NEMA has changed some of the terminology for these higher efficiency (IE 4 level) motors with “Super Premium” becoming “Premium 4.”
The revisions added new nominal and minimum full-load efficiencies for 2-, 4-, 6- and 8-pole open motors rated 1-75hp, and 300-750hp. The original edition covered 2-, 4-, 6- and 8-pole open motors rated 100-250hp. Publication of the new Table 12-23 will occur in 2026 as part of the next edition of NEMA MG 00001.
The revised table can be downloaded using the link below. It is effective immediately for manufacturers to mark these efficiency levels on their applicable motor nameplates.
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