Specifies mechanical and electrical requirements and dimensions for footmounted d.c. mill auxiliary motors for heavy duty steel mill service. Covers series, compound, shunt, compositely and separately excited motors and motors with compensating winding, with rated voltages of 230 V, 460 V and 550 V, with rated outputs 3.75 kW to 243 kW, and rated speeds 360 rev/min to 1130 rev/min.