DC motors, like AC motors, can be configured to turn in either direction. Their direction can be easily controlled by inverting the polarity of the applied armature voltage by reversing the armature leads. This works with shunt, series, and compound wound DC motors.
How do you reverse the rotation of a DC motor?
The direction of rotation of a dc motor can be reversed:
- By reversing the connections of both armature and the field windings with the supply.
- By reducing the field flux.
- By reversing the connections of either the armature or the field winding connection with the supply.
What happens if you turn a DC motor backwards?
If you try to stop or reverse it manually, then it will try to draw whatever current is needed to continue running at that speed. The high current could heat the motor to the point of damage, unless the power supply limits the current.
How can you make a motor spin faster?
ANSWER: In order to make the motor spin faster or slower you must increase or decrease the strength of the magnetic field. This is done by either changing the amount of current running through the motor or varying the distance of the permanent magnets from the motor.
How can you tell if a DC motor is positive or negative?
You’re measuring voltage because the definition of a DC voltage source is a dipole of charges, positive and negative. Touch red to one wire and black to the other. If the value is negative (-), switch the probes on the wires and the voltage should be positive. The wire in contact with the red probe is (+).
Can you reverse an electric motor?
Motor rotation is essentially created by the manipulation of wires and magnetic fields. Thus, you can often reverse AC motors by switching the wire connections. This is as easy as unhooking and re-crimping the designated wires.
How much voltage drop does it take to cause problems to a motor?
In general, satisfactory motor performance requires a voltage within ± 5% of its rated nominal value in steady-state operation, Starting current of a motor can be 5 to 7 times its full-load value (or even higher). If an 8% voltage drop occurs at full-load current, then a drop of 40% or more will occur during start-up.
What would cause a fan motor to run backwards?
Watch out: yes it is indeed possible for some electric motors to run “backwards” following damage to the motor’s start capacitor or windings. … For example the blower fan motor in an air handler can start and run backwards as can some air conditioner compressor unit cooling fan motors.