Lincoln Electric SVM194-A service manual DC Generator Machines

E-11	THEORY OF OPERATION	E-11
	FIGURE E.10 - DC GENERATOR MACHINES

Return to Section TOC Return to Master TOC

Return to Section TOC Return to Master TOC

MECHANICAL

COUPLING

DC GENERATOR MACHINES

	C
F	U
	R
I	R
E	E
L	N
D	T
SHUNT FIELD WINDINGS	DC CURRENT
MAGNETIC FIELD
GENERATOR	BRUSH
	ARMATURE
	SHAFT
ARMATURE	BRUSH
MAGNETIC FIELD	DC CURRENT
SHUNT FIELD WINDINGS
	C
F	U
	R
I	R
E	E
L	N
D	T

Return to Section TOC Return to Master TOC

Return to Section TOC Return to Master TOC

The armature winding of a DC generator is located on the rotating member. Current is conducted from it by means of carbon brushes. The field winding is located in the stator, which is stationary, and is excited by direct current. The armature coil sides are placed at opposite points on the rotating shaft with the conductors parallel to the shaft. The armature assembly is normally turned at a constant speed by a source of mechanical power connected to the shaft. Rotation of the armature through the magnetic field produced by the stationary field winding induces a coil voltage in the armature winding. The voltage induced in an individual armature coil is an alternating (AC) voltage, which must be recti- fied. In a conventional machine, rectification is provid- ed mechanically by means of a commutator. A commu- tator is a cylinder formed of copper segments insulated from each other and mounted on, but insulated from, the rotating shaft. Each copper segment is connected to a corresponding armature winding. Stationary car- bon brushes held against the commutator surface con- nect the armature windings to external terminals. The commutator provides full-wave rectification, transform- ing the voltage waveform between brushes and mak- ing available a DC voltage to the external circuit.

NOTE: Unshaded areas of Block Logic Diagram are the subject of discussion

CLASSIC® 300D & 300G