Motors Flashcards
Why would you talk to Operations prior to working on a motor?
Process interuption.
To understand process prior to failure.
How would you find replacement parts?
Obtain motor information from name plate and contact our planning staff.
What are the most common failures that occur within a motor?
Windings and bearings.
What are two common ways to test motor windings?
Ohm testing with a multimeter.
Insulation integrity testing with a megger.
What is the most reliable winding test?
Megger.
What shoukd you do to a wire after you have megged it out?
Discharge the wire by touching it to ground.
What methods are used to determine that the bearings are going bad?
Amperage on motor is slightly higher than listed on nameplate.
Sound that the motor makes.
What instrument is used to check motor amperage?
Clamp on amp probe.
When do you LOTO a motor?
When I need to disconnect motor leads or remove any guards.
Where do you place your lock when LOTO-ing a motor?
On the MCC bucket, lock box or starter panel.
What should be checked when a motor is replaced?
Motor amperage.
Rotation.
How do you change the rotation of a three-phase motor?
Switch any two of the three phases.
How do you check rotation?
Bump test the motor with the load disconnected.
What kind of information can you find on a motor nameplate?
HP, voltage, rpm, frame size, amperage, single vs two speed, single vs dual voltage, area classification rating.
What does TEFC stand for?
Totaly Enclosed Fan Cooled.
