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59 Cards in this Set
- Front
- Back
- 3rd side (hint)
what is the most common motor in the industry? |
induction motors |
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how many leads come out of a connection box commonly? |
9 leads |
pg 2 |
|
duel voltage motors are designed to operate on either |
240 or 480 |
pg 2 |
|
a single voltage 3 phrase stator has how many windings? |
3 groups or 3 |
pg 2 |
|
a single voltage motor has how many leads? |
6 leads |
pg 2 |
|
how are each leads labeled? |
1 t1 t4 2 t2 t5 3 t3 t6 t1 t2 t3 winding starts t4 t5 t6 winding finishes |
pg 2 |
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where are t4 t5 t6 connected? |
stator |
pg 2 |
|
ic uses what labels instead? |
u v and w |
pg 2 |
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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 |
counter clockwise |
pg 3 |
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review page 3 - observe inversion |
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duel voltage motors have how many windings? |
6 windings or groups of windings |
pg 3 |
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review page 4 5 6 for transformer variety hook ups |
page 4 |
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|
wye and delta high voltage connections are |
the same |
pg 5 |
|
to apply full voltage starter us |
across the line starters |
pg 9 |
|
reduced voltage starters |
provide reduced voltage at start and full at run |
pg 9 |
|
full voltage manual and magnetic starters apply full voltage at |
instant of start with currents of typically 500-600% of full load and 150% of full load torque |
pg 9 |
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reduced voltage starters have what problem |
lower starting torque |
pg 9 |
|
cec rules on disconnects |
manual must be on line side of motor |
pg 10 |
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part winding starters and motors work how |
|
pg 10 |
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part winding motor in rushed current is reduced ________ |
60 to 65 percent of in rush current if both windings are on |
pg 11 |
|
if the full load is present the motor could be damaged if |
the starter does not switch to energize both windings within 2 seconds in a part winding motor |
pg 11 |
|
reduced voltage starter is used when the high starting current can cause |
excess voltage drop or voltage sag for the system |
pg 11 |
|
reduced voltage starters can cause damage to |
fragile or high inertia loads by the sudden imposition |
pg 12 |
|
belt driven fan and other loads similar have |
quiter starts when started at reduced voltage |
pg12 |
|
voltage starters may incorporate what? |
timing relays |
pg 12 |
|
on delay relay |
the delay occurs after the relay coil is energized |
pg 12 |
|
on delay is also called |
tdoe |
pg 12 |
|
off delay relay |
the delay occurs after the coil is de energized |
pg 12 |
|
off relay is also called |
TDOD |
pg 12 |
|
to and tc mean |
time open and time closed |
pg 12 |
|
some timing relays can have |
instantaneous contacts |
pg 12 |
|
review and memorize |
|
pg 12 |
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how are auto transformers used in starters |
|
pg 13 |
|
reduced voltage current formula and what are the units of measurements |
|
pg 13 |
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starting line current to an auto transformer starter is proportional to |
square of starting motors voltage |
pg 13 |
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review pages 13 and 14 on calculating reduced voltage current |
yes |
|
|
starting torque is calculated as |
|
pg 14 |
|
an auto transformer has how many current reductions |
2 |
pg 14 |
|
review bottom paragraph of page 14 dealing with taps and reduction of current |
yes |
|
|
auto transformers can be |
open or closed transition starters |
pg 15 |
|
open transition starters momentarily disconnect the line during reduced voltage starting to full voltage starting |
pg 15 |
|
|
closed transition starters maintain current to motor through the |
auto transformer windings from reduced voltage to full voltage |
pg 15 |
|
open transition starters have higher transition currents, higher torque changes and torque bumps have a |
quick fall and rise |
pg 15 |
|
how does a control and power circuit start transition and run? |
table 1 on page 16 |
|
|
inrush current is larger when |
delta connected and it is root 3 bigger |
pg17 |
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wye delta starter reduces the inrush to a ___ and similarly the ___ |
1/3 and torque |
pg17 |
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this starting torque is |
|
pg 17 |
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explain open transition wye a delta starter overload setting and process of starting transition and running starting transition and running |
pg 18 19 |
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make sure to read and study pg 20 and on |
electronic soft starters I did not make cards yet too much info |
|
|
phase converters that allow |
3phase to run on single phase |
pg 24 |
|
phase converters are 120° apart? |
no almost 120 but not equal |
pg 24 |
|
you would install phase converters instead of 3 phase because |
it's cheaper than a new install sometimes |
pg 24 |
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single phase motors are worse in most ways but fractional horse power motors are |
read pg 24 last paragraph |
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there are 2 types of phase converters what are they and what's the difference |
|
pg 25 |
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rotary phase converters look like |
induction motors without an output shaft |
pg 25 |
|
electrolytic capacitor supplies a leading current to help |
start the induction motor generator |
pg 25 |
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once started explain the process the electrolytic capacitor is... explain this process |
|
pg 25 |
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review pgs 26 27 28 to much to explain atm |
what did you read? |
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phase converters are 120° apart? |
no not truly |
pg 24 |