General
All AC machines achieve rotation due to this
Stator RMF
TRIPLE PLAY
name the 3 types of 3 phase motors discussed in class
SCIM, WRIM, SYNCH
If a Synchronous motor is rotating at 1200 RPM. What is the speed of the rotating magnetic field of the stator?
1200RPM
WRIM's were used due to this operating characteristic
High starting torque/amp
TRIPLE PLAY!
Name the 3 types of single phase motors discussed in class
Resistance start induction run
Cap start induction run
Cap start Cap run
the letter code associaetd with each motor refers to what?
rotor construction/ type
This is how you change the rotation of a 3 phase motor
swap any two leads
What voltage is used for the excitation current of a separately excited synchronous motor
DC
The 3 lines going to the stator are T1-3
What are the 3 lines connecting to the rotor numbered?
M1-3
What are the names of the 2 windings in a single phase motor?
Start/Aux and Run/Main
The part of an AC motor that rotates is referred to as a
rotor
This tool can be useful when bumping a motor is not an option
Phase analyzer
This is the name given to the set of rotor bars in a separately excited motor
Amourtissuer winding
How do these machines allow for connection to a bank of resistors to the rotor?
Slip rings
In what application discussed in class would you see a single phase motor in the elevating industry?
residential lifts
This is the formula for calculating Synchronous speed
SS= 120xF/P
Concerning dual voltage motors, how should windings be connected in relation to one another for low voltage operation?
Parallel
This is how a PMSM is able to achieve its rotation
Slowly increase frequency to stator
Where in the industry would you expect to see a WRIM?
Older geared traction elevators
To disconnect the start winding of a Cap start induction run motor.
What percentage of voltage fluctuation are motors constructed to withstand?
10%
Single phasing
DAILY DOUBLE- BE SPECIFIC
If a synchronous motor was started with excitation current flowing, what would the effect be on motor operation.
No, stator field too fast therefore cannot over come own inertia and will be attracted and repelled quickly, rocking in place.
Variable resistor OR fixed resistor/ contact network
What would happen upon start up if a single phase motors centrifugal switch failed open?
No rotation, would not start.