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Two lead motor
Another way to refer a shaded pole induction motor?
DRAW 2 POSITION DOUBLE BREAK PG 121
DRAW 2 POSITION DOUBLE BREAK PG 121
DRAW 2 POSITION SINGLE BREAK PG 121
DRAW 2 POSITION SINGLE BREAK PG 121
DRAW 3 POSITION DOUBLE BREAK PG 121
DRAW 3 POSITION DOUBLE BREAK PG 121
DRAW 3 POSITION SINGLE BREAK PG 121
DRAW 3 POSITION SINGLE BREAK PG 121
shaded coil
In a shaded pole induction motor, the rotating magnetic field is created by a?
air timers
Pnuematic timers are often referred to as?
Current
The movement of electrons is called?
True
True or False. Electrons have a negative charge.
False
True or False. Voltage is not the force that causes electrons to move.
False
True or False. You can have a voltage at only one point.
True
True or False. You can only have a voltage when you have a difference of electrical potential between two points.
True
True or False. ground is commonly connected to the neutral and sometimes to Line 2
True
True or False. split phase or P.S.C motor can be reversed by changing the direction of current flow through the start or run winding but not both.
Voltage
What is the measurement of the difference of electrical potential between 2 points.
circuit breakers and fuses
What provides short circuit protection?
pnuematic timers
What type of timer operate by restricting the flow of air through an orifice to a rubber bellows or diaphragm?
Permanent split capacitor
Whats P.S.C stand for?
branch circuit
Whats everything (loads, devices, conductors, etc.) after the final over current device.
magnetic starter
a contactor with an overload relay assembly
N.C.T.O
abbreviation for normally close time delay to open
N.C.T.C
abbreviation for normally close time delay to re-close
N.O.T.C
abbreviation for normally open time delay in closing
N.O.T.O
abbreviation for normally open time delay to re-open
8 times per hour
although the capacitor-start induction run motor has a high starting torque, the motor should not be started more than ?
overload
another word for running protection?
short circuit
another word for starting protection?
contactor
big relay. handles higher current 10A or more.
one direction
dc flows in how many directions?
heat
electric current produces?
thermal devices
electrical circuits can be protected against overloads by ?
relay
electromagnetic switch. solenoid and plunger device
600 volts or less
how many volts does fuses go up too?
bigger wire (thicker)
if the motor flc is high the stator winding must be made out of?
small wire
if the motor flc is low the stator winding must be made out of?
cannot
if the selector switch is in the off position the coil ____ be energized and the motor will be off.
automatic
in the ______ position, the coil will only be energized when the 2 wire pilot device is in its closed position.
stator windings
long piece of wires that has been covered with a very thin coating of insulation and wrapped into a coil
coil, plunger, contacts
main parts of the relay is ?
40%
no load current is approximately how many percentage of flc?
Electrical charge
objects become electrically charged by adding or removing electrons from them.
10
pilot devices are usually designed to carry how many amps max?
fractional
shaded pole motor are generally used for fractional or integral horsepower motors?
ground fault
special kind of short circuit that occurs when one of the line conductors comes into direct contact with a grounded metal part of the electrical system.
motor current
the current drawn by a motor is proportional to its load. the greater the load connected to the shaft of the motor, the more current the motor must draw to enable its shaft to move the load.
full load current
the current drawn by a motor when its producing its rated horsepower at its rated torque.
locked rotor current
the current drawn by a motor when the shaft is unable to turn. it is approximately 6 times the full load current. also called the "in rush" current
no load current
the current drawn by the motor windings when there is nothing connected to the shaft of the motor.
voltage
the difference of electrical potential between two points
draw more current
the only way a motor can produce more power is to?
feeders
the wires or circuits that connect between panels or enclosures
synchronous speed
this refers to the speed of the rotating magnetic field of the stator?
resistive, inductive and capacitive
three types of AC loads are?
sine, square, sawtooth
three types of ac wave forms are?
common, separate, control circuit transformer
three types of control circuits.
pure, varying, pulsating
three types of dc wave forms are?
Add electrons
to give an object a negative charge
Remove electrons
to give an object a positive charge
False
true or false The plunger is not being held closed by a latch on a latching relay.
true
true or false. a relay is not a manual switch. you don't manually open or close a relays contact as you would a toggle switch
false
true or false. ac reverses its direction of current flow never at periodic intervals.
false
true or false. branch circuits never connects to loads.
true
true or false. feeders never connect to loads.
true
true or false. fuses come in many shape and sizes.
false
true or false. inductors does not oppose a change of current
True
true or false. latching relays (contactor) has 2 coils (on and off)
false
true or false. pilot devices and selector switches cannot be used with manual motor starters.
True
true or false. pneumatic timers are unaffected by variations in ambient temperature or atmospheric pressure.
true
true or false. the 2 characteristics of resistive loads are they produce heat and the voltage and current are in phase.
true
true or false. three types of split phase motors are resistance start induction run, capacitor start induction run and capacitor start capacitor run
false
true or false. timing relays do not have timed contacts
true
true or false. you cannot change the voltage applied to a motor when the motor needs to produce more power.
Two leads
voltmeters has how many leads?
horsepower
volts x amps
pushbuttons
what are momentary contact devices?
inductor
what is a coil of wire?
shaded pole motor
what is another common type of single phase induction motor?
trip free
what is it called when the contacts of manual motor starters cannot be held closed manually when the overload relay has tripped.
HAND OFF AUTOMATIC switch
what is used so a motor can be controlled manually by an operator or automatically by using a 2 wire pilot?
manual motor starter
what motor has an on-off switch with motor overload protection?
dc motor
what motor works on the principle of the attraction and repulsion of magnetic fields.
induction motor
what motor works on the principle of the rotating magnetic field?
overload heater
what provides running protection?
clearing contacts
what type of contacts you use when a latching relay is controlled by a maintained contact device?
pushbutton interlocking
what type of interlocking prevents 2 coils from being energized at the same time
mechanical interlocking
what type of interlocking prevents 2 plungers from being closed at the same time.
contact interlocking
what type of interlocking prevents two or more coils to be energized at the same time
L1, L2, L3, N
what're the four possible different electric potentials?
conductor, magnetic field, movement
what're the three things magnetic induction need to take place?
overload, short circuit, ground fault
what're the three types of over current?
fractional hp and integral hp
what're the two types of manual motor starters?
overload
when the current drawn by a load exceeds the rated ampacity of the circuit conductors.
off delay
when the relay coil is energized, the off delay contacts go to their alternate position immediately. When the coil is de-energized, the contacts delay returning to their normal position. what type of delay is this?
on delay
when the relay coil is energized, there is a delay until the contacts go to their alternate state position. when the coil is de-energized, on delay contacts will return to their normal position immediately, without a delay. What type of delay is this?
short circuit
when there is a low impedance path for current that by-passes the load.
control and power
when using an electromagnetic switch (relay or contactor) to control a load, what are the 2 separate circuits?
service
where the power from the utility company enters the building. this includes the meter and the main fuses or breaker and the enclosure they're located in
off coil
which coil controls the latch on a latching relay?
No charge
zero potential is a place in a circuit where there is?