EMC Chapter 7 Flashcards
A(n)___ is a magnet whose magnetic energy is produced by the flow of electric current.
electromagnet
An electromagnet consists of an ___ core inserted into a coil.
iron
The left-hand rule states that if the fingers of the left hand are wrapped in the direction of the current flow of the coil, the thumb points to the magnetic ___ pole of the coil.
north
An electromagnet’s strength can be controlled by regulating its ___.
electric current
The strength of a magnetic field and current are ___ related.
directly
A(n)___ is the movable part of a solenoid.
armature
There are ___ different solenoid configurations.
five
A ___ solenoid uses a lever attached to an armature to transform the armature’s vertical action into a horizontal action.
bell-crank
___ current is unwanted current induced in the metal structure of a device due to the rate of change in the induced magnetic field.
Eddy
A(n)___ coil sets up an auxiliary magnetic field that helps hold in the armature as the main coil magnetic field drops to zero in an AC circuit.
shading
A ___ is an electric output device that coverts electrical energy into a linear mechanical force
solenoid
A(n)___ is a single turn of conducting material (normally copper or aluminum) mounted on the face of the magnetic laminate assembly or armature of a solenoid.
shading coil
Magnetic coils are normally constructed of many turns of insulated ___ wire wound on a spool.
copper
In a solenoid coil, the inrush current is approximately ___ times the sealed current.
6 to 10
The magnetic opposition upon energizing a solenoid is referred to as ___ reactance or total impedance.
inductive
Magnetic coil data is normally given in ___.
volt amperes
___ voltage is the minimum voltage that causes the armature to start to move.
Pick-up
For most solenoids, the minimum pick-up voltage is about ___ of the solenoid rated voltage.
80% to 85%
Drop-out voltage can be as low as ___% of the solenoid rated voltage.
70
___ variations are one of the most common causes of solenoid failure.
Voltage
A solenoid’s ___ is usually given in operations per minute.
duty cycle
___ voltage is the minimum control voltage required to cause the armature to seal against the pole faces of the magnet.
Seal-in
A ___ control valve is a valve that is used to direct the flow of fluid throughout a fluid power system.
directional
A ___ is the number of locations within the valve in which the spool can be placed to direct fluid through the valve.
position
A ___ is a flow path through a valve.
way
___-way valves are used as shutoff, check, and quick-exhaust valves.
Two
___ use fluid power, cylinders, actuators, and grippers to provide the required power and movement.
Industrial robots
___ are used to help determine the cause of solenoid failure.
Manufacturer charts
The voltage applied to a solenoid should be +-___% of the solenoid rated value.
10
A ___ circuit is a circuit that suppresses noise and high voltage on the power lines.
snubber
A solenoid ___ when the voltage is excessive.
overheats
A solenoid draws ___ current when first connected to power.
several times its rated
Solenoids usually fail due to electrical problems or ___.
mechanical damage
