Three-Phase Motors And Starters

Front 1

what is the most common motor in the industry?

Back 1

induction motors

Front 2

how many leads come out of a connection box commonly?

Back 2

9 leads

Hint 2

pg 2

Front 3

duel voltage motors are designed to operate on either

Back 3

240 or 480

Hint 3

pg 2

Front 4

a single voltage 3 phrase stator has how many windings?

Back 4

3 groups or 3

Hint 4

pg 2

Front 5

a single voltage motor has how many leads?

Back 5

6 leads

Hint 5

pg 2

Front 6

how are each leads labeled?

Back 6

1 t1 t4

2 t2 t5

3 t3 t6

t1 t2 t3 winding starts

t4 t5 t6 winding finishes

Hint 6

pg 2

Front 7

where are t4 t5 t6 connected?

Back 7

stator

Hint 7

pg 2

Front 8

ic uses what labels instead?

Back 8

u v and w

Hint 8

pg 2

Front 9

motors rotation is going in what direction when looking at not drive end when hooked up to t1 t2 and t3 with l1 l2 l3 accordingly

Back 9

counter clockwise

Hint 9

pg 3

Front 10

review page 3 - observe inversion

Back 10

Front 11

duel voltage motors have how many windings?

Back 11

6 windings or groups of windings

Hint 11

pg 3

Front 12

review page 4 5 6 for transformer variety hook ups

Back 12

page 4

Front 13

wye and delta high voltage connections are

Back 13

the same

Hint 13

pg 5

Front 14

to apply full voltage starter us

Back 14

across the line starters

Hint 14

pg 9

Front 15

reduced voltage starters

Back 15

provide reduced voltage at start and full at run

Hint 15

pg 9

Front 16

full voltage manual and magnetic starters apply full voltage at

Back 16

instant of start with currents of typically 500-600% of full load

and 150% of full load torque

Hint 16

pg 9

Front 17

reduced voltage starters have what problem

Back 17

lower starting torque

Hint 17

pg 9

Front 18

cec rules on disconnects

Back 18

manual must be on line side of motor

Hint 18

pg 10

Front 19

part winding starters and motors work how

Back 19

Hint 19

pg 10

Front 20

part winding motor in rushed current is reduced ________

Back 20

60 to 65 percent of in rush current if both windings are on

Hint 20

pg 11

Front 21

if the full load is present the motor could be damaged if

Back 21

the starter does not switch to energize both windings within 2 seconds in a part winding motor

Hint 21

pg 11

Front 22

reduced voltage starter is used when the high starting current can cause

Back 22

excess voltage drop or voltage sag for the system

Hint 22

pg 11

Front 23

reduced voltage starters can cause damage to

Back 23

fragile or high inertia loads by the sudden imposition

Hint 23

pg 12

Front 24

belt driven fan and other loads similar have

Back 24

quiter starts when started at reduced voltage

Hint 24

pg12

Front 25

voltage starters may incorporate what?

Back 25

timing relays

Hint 25

pg 12

Front 26

on delay relay

Back 26

the delay occurs after the relay coil is energized

Hint 26

pg 12

Front 27

on delay is also called

Back 27

tdoe

Hint 27

pg 12

Front 28

off delay relay

Back 28

the delay occurs after the coil is de energized

Hint 28

pg 12

Front 29

off relay is also called

Back 29

TDOD

Hint 29

pg 12

Front 30

to and tc mean

Back 30

time open and time closed

Hint 30

pg 12

Front 31

some timing relays can have

Back 31

instantaneous contacts

Hint 31

pg 12

Front 32

review and memorize

Back 32

Hint 32

pg 12

Front 33

how are auto transformers used in starters

Back 33

Hint 33

pg 13

Front 34

reduced voltage current formula and what are the units of measurements

Back 34

Hint 34

pg 13

Front 35

starting line current to an auto transformer starter is proportional to

Back 35

square of starting motors voltage

Hint 35

pg 13

Front 36

review pages 13 and 14 on calculating reduced voltage current

Back 36

yes

Front 37

starting torque is calculated as

Back 37

Hint 37

pg 14

Front 38

an auto transformer has how many current reductions

Back 38

2

Hint 38

pg 14

Front 39

review bottom paragraph of page 14 dealing with taps and reduction of current

Back 39

yes

Front 40

auto transformers can be

Back 40

open or closed transition starters

Hint 40

pg 15

Front 41

open transition starters momentarily disconnect the line during reduced voltage starting to full voltage starting

Back 41

pg 15

Front 42

closed transition starters maintain current to motor through the

Back 42

auto transformer windings from reduced voltage to full voltage

Hint 42

pg 15

Front 43

open transition starters have higher transition currents, higher torque changes and torque bumps have a

Back 43

quick fall and rise

Hint 43

pg 15

Front 44

how does a control and power circuit start transition and run?

Back 44

table 1 on page 16

Front 45

inrush current is larger when

Back 45

delta connected and it is root 3 bigger

Hint 45

pg17

Front 46

wye delta starter reduces the inrush to a ___ and similarly the ___

Back 46

1/3 and torque

Hint 46

pg17

Front 47

this starting torque is

Back 47

Hint 47

pg 17

Front 48

explain open transition wye a delta starter

overload setting and

process of starting transition and running

starting transition and running

Back 48

pg 18 19

Front 49

make sure to read and study pg 20 and on

Back 49

electronic soft starters I did not make cards yet too much info

Hint 49

Front 50

phase converters that allow

Back 50

3phase to run on single phase

Hint 50

pg 24

Front 51

phase converters are 120° apart?

Back 51

no almost 120 but not equal

Hint 51

pg 24

Front 52

you would install phase converters instead of 3 phase because

Back 52

it's cheaper than a new install sometimes

Hint 52

pg 24

Front 53

single phase motors are worse in most ways but fractional horse power motors are

Back 53

read pg 24 last paragraph

Front 54

there are 2 types of phase converters what are they and what's the difference

Back 54

Hint 54

pg 25

Front 55

rotary phase converters look like

Back 55

induction motors without an output shaft

Hint 55

pg 25

Front 56

electrolytic capacitor supplies a leading current to help

Back 56

start the induction motor generator

Hint 56

pg 25

Front 57

once started explain the process the electrolytic capacitor is... explain this process

Back 57

Hint 57

pg 25

Front 58

review pgs 26 27 28 to much to explain atm

Back 58

what did you read?

Front 59

phase converters are 120° apart?

Back 59

no not truly

Hint 59

pg 24