Shunt Motor Flashcards
What is the defining characteristic of a shunt DC motor?
The shunt field winding consists of many turns of relatively small wire and is connected in parallel with the armature.
How does armature current affect the flux in a shunt DC motor?
The strong magnetomotive force and resulting flux produced by the small amount of shunt field current is not significantly affected by the armature current flow.
What device is used to control the field flux in a shunt DC motor?
A shunt field rheostat.
What is the relationship between torque and armature current in a shunt DC motor?
Torque changes that occur with mechanical load changes are mainly due to the change in armature current.
What is the equation for torque in a shunt DC motor?
T1 = k * Ф x larm T.
How does the starting torque of a shunt DC motor compare to other motor types?
The starting torque is relatively low compared to the other motor types.
How do speed changes from no-load to full-load in a shunt DC motor compare to other motor types?
The speed changes are relatively small as compared to the other motor types, providing excellent speed regulation.
What can be done to achieve speeds above base speed in a shunt DC motor?
Increase the resistance of the shunt field rheostat.
What condition may occur if the field current is too low or non-existent in a shunt DC motor?
Runaway conditions will typically occur.
Will a shunt DC motor operate at safe no-load speeds if the field winding is connected?
Yes, it will operate at safe no-load speeds.
Fill in the blank: A shunt field winding consists of many turns of relatively _______ wire.
small
