Relay Final Flashcards
What are other names for an elementary diagram?
schematic or 1 line diagram, Elementry
How does a reversible motor starter change direction on a 3 phase motor?
Change any two leads
What is the formula for figuring the speed of a motor?
Speed =2 (60) (60) RBN. --------------------- # of Poles
In pneumatic timers the timing is accomplished by ?
It pushes air through an Orpheus.
What are the two basic types of induction motors?
A: wire wound
B: Squirrel Cage
Frequent starting and stopping a motor is called ?
Jogging
_____________ is the difference between the speed of rotational field and the actual rotation of the motor.?
Slip.
A stationary part of a magnetic starter is called the ________ And the moving part is _________?
A: Magnetic Assembly
B: Armature Assembly
The current that a motor draws on start up is ______ to ________ times as normal operating current?
Five - Seven
Manufacturers sometimes give a __________ _________ on the name plate?
Service Factors
When a motor is first started , the current it draws is called _______ or _______ current?
A: In a rush
B: Locked Rotor
The temperature of the air that surrounds you or the enclosed is called what?
Ambient Temp
2 types of starters are ___________, and ____________?
A: Magnetic
B: Manual
What is the manual starter switch called?
Drump switch
Manual starters have low voltage _________ only?
Release.
Magnetic starters have low voltage _______?
Protection
Excessive noise can be caused by a broken _________?
Shading Coil
A/C coil should always be connected in ________ as opposed to series.
Parallel
Fuses are for _______ __________ only
Short Circuit
Unlike fuses overload relays are ??-
Reusable
Overload relays can be classified as ___________ or _______
Magnetic Thermal
Two class of thermal overloads are ?
Bimetalic Melting Alloy
Another name for a melting alloy is a __________?
Solder Pot.
A 3 wire control system uses __________ or ________
A: Push Button
B: Momentary Contacter
Control transformer operates at __________ voltage on secondary,____________ and the other is _____?
A: 120
B: Grounded
C: Hot
A pilot device is operated by________ means?
Mechanical means
The holding circuit interlock (seal in ) contact is wired and is parallel to the start button, is used in ___________ wire control systems
3
The ____________ usually has the highest voltage and current.
The power section
_____________ is when a motor is stopped very rapidly by reversing the rotation… ( is used in a 3 wire)
Plugging
What drawing shows all the parts as closely as possibly is called a ___________ .
Wiring Diagram