What is a cause of generator brush arcing?
What is the cause of generator brush arcing? Low spring tension.
What are the characteristics of a DC series wound motor?
Characteristics of a DC Series Motors:
- Speed-Current Characteristic:
- Since on no load the series motor attains dangerously high speed, which causes heavy centrifugal force resulting in the damage of machine, series motors are not suitable for the services:
- Torque-Current Characteristic:
- Speed-Torque Characteristic:
How does the magnetic brake use to stop the rotation of an electric motor armature operates?
How does the magnetic brake used to stop rotation of an electric motor armature operation? A friction brake is applied by a spring and released by a magnet. … changes alternating current produced in the armature into direct current as it is taken from the armature..
What is the working principle of DC series motor?
What is DC Motor? The DC motor is the motor which converts the direct current into the mechanical work. It works on the principle of Lorentz Law, which states that “the current carrying conductor placed in a magnetic and electric field experience a force”.
What are different reasons for sparking in commutator?
Following is a brief rundown of the more common causes of sparking, along with suggestions for their diagnosis and treatment.
- Brush Holders not equally spaced. …
- Brush holders off electrical neutral. …
- Brush Holders damaged or dirty. …
- Holders too far from commutator surface. …
- Wrong interpole strength. …
Which is the most effective method of balancing armature?
The best way to minimize balance problems, is to minimize the initial unbalance which will need to be corrected. Unbalance in a small electric motor can be split into two categories, unbalance that is created BEFORE the armature is balanced, and unbalance that is created AFTER the armature is balance.
Which DC motor is preferred for constant speed?
Explanation: Rotary compressor generally demand constant speed operation throughout the load. Sometimes, DC machines are not able to produce constant speed throughout the process hence, synchronous machine is used. 4.
What is the difference between field current and armature current?
The field of a machine is the part that generates the direct magnetic field. The current in the field does not alternate. The armature winding is that which generates or has an alternating voltage applied to it.
How can the direction of rotation of a DC electric motor be changed?
So in order to change the direction of rotation, we can simply reverse the voltage, causing the current to flow in the opposite direction, changing the force by 180 degrees and the motor to be driven ‘backwards’.