ANSI C50.4

Description / Abstract: This standard applies to direct-current motors and generators They are arranged under six classifications according to machine size and type as follows:

(1) General

(2) Fractional-horsepower motors and generators

(3) Integral-horsepower motors

(4) Integral-horsepower generators

(5) Large motors

(6) Large generators

Section 4-2 of this standard applies to all motors and generators Section 4-3 applies to machines built in a frame smaller than that having a continuous rating of 1 hp, open construction at 1,700-1,800 rpm. Section 4-4 applies to motors larger than those in Section 4-3 up to and including motors rated 0.75 hp/rpm. Section 4-5 applies to generators larger than those in Section 4-3 up to and including generators rated 0.60 kw/rpm. Section 46 applies to motors larger than those in Section 4-4. Section 4-7 applies to generators larger than those in Section 4-5.

Excluded from the scope of this standard are the following:

(1) Machines for traction use [see American Standard for Rotating Electric Machinery Forming a Part of the Power Equipment Electrically Propelled Railway Cars, Railway Locomotives and Coaches (Trolley and Prime Mover), C35.1-1962 (IEEE Publication No.11, August 1962) .]

(2) Rotating exciters for synchronous machines within the scope of American Standard Rotating Exciters for Synchronous Machines, C50.5-1955.

(3) Mill motors within the scope of American Institute of Steel Engineers Standard for Mill Motors, Std. No.1, 1957.

(4) Machines used in aircraft or automotive equipment.