Save
Busy. Please wait.
Log in with Clever
or

show password
Forgot Password?

Don't have an account?  Sign up 
Sign up using Clever
or

Username is available taken
show password


Make sure to remember your password. If you forget it there is no way for StudyStack to send you a reset link. You would need to create a new account.
Your email address is only used to allow you to reset your password. See our Privacy Policy and Terms of Service.


Already a StudyStack user? Log In

Reset Password
Enter the associated with your account, and we'll email you a link to reset your password.
focusNode
Didn't know it?
click below
 
Knew it?
click below
Don't Know
Remaining cards (0)
Know
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.

  Normal Size     Small Size show me how

Controls

Units 2 & 3

QuestionAnswer
The heavier lines on electrical diagrams usually indicate the control circuit conductors False
In a ladder diagram components are arranged according to their physical position in the installation False
The conductors feeding to a large motor would be considered to be part of the control circuit False
When more than one electrical load is connected in a rung of a ladder diagram, the loads are normally connected in series False
Wires common to each other are usually identified by the same number True
If a control circuit is supplied from a grounded circuit, it makes no difference what side of the line is grounded False
Wiring diagrams are used when installing and tracing wires in electrical installations True
With low-voltage protection, when power is restored after a power failure, manual restarting is required True
No wires or components are normally shown on block diagrams True
The direction of rotation of a DC motor depends on the direction of the magnetic field and the direction of the current flow through the armature True
Motor terminal markings are usually used to tag only those terminals to which connections must be made from external circuits True
Single-phase AC motors are typically constructed in small horsepower sizes True
All 3-phase motors are wired so that the phases are connected in either Wye or Delta configuration True
The rated nameplate speed of a motor is its approximate speed with no load applied False
The motor nameplate Design letter is an indication of the motors torque speed curve True
A motor with a low power factor rating will draw less current for the same horsepower than a motor with a high power factor False
Two-wire control circuits are designed to protect against automatic restarting when power returns after a power failure False
Ladder diagrams show the electrical connections
The two basic parts of a typical motor circuit are the control circuit and power circuit
On a ladder diagram, all wires that connect to a common point are assigned the same numbers
Which of the following diagrams shows an electrical installation reduced to its simplest form single-line diagram
In a dual-voltage split-phase motor, the two run windings are connected in ___ for the High voltage operation series
When a split-phase motor is operated with a capacitor in series with one of the stator windings the starting torque is higher
The speed of an AC induction motor depends on the voltage of the electrical power supply and number of poles built into the motor
NEMA requires that the motor be able to carry their rated horsepower at nameplate voltage plus or minus 10%
Standard NEMA motor insulation classes are given by alphabetic classification
A motor nameplate indicates that the motor has a "service factor" of 1.25. This means that the motor can on occasion safely develop 125% of its HP
The nameplate of a motor indicates that its thermal protected. This means the motor has a built in thermal device
The plugging of a motor refers to braking by reverse rotation
With "low voltage protection" motor control is a power failure disconnects service and when power is restored manual restarting is required
Which of thhe following types of motor starters connects the motor directly to the supply line on starting? full voltage starter
Two-wired control circuits use a ___-contact type of control device maintained
A ladder diagram is a _____ representation of an electric circuit schematic
On electrical diagrams, conductors that cross each other and make contact are represented by a heavy ___ at the junction dot
For a ____ connection of loads, the voltage across load is the same as that of the applied voltage parallel
On a ladder diagram, a line is defined as a complete ___ from L1 to L2 that contains a load path
A wiring diagram is intended to show the actual ____ of all components location
Industrial applications use DC motors because the ___/____ relationship can be easily varied speed/torque
The rotating part of an AC motor is referred to as the ___; the stationary part is called the ____ rotor, stator
The phase rating of a motor is listed on the nameplate as ___,____,____ DC, 1-phase, 3-phase
The amount the motor winding temperature will increase above the ambient at full load is specified according to the nameplate _______ rating temperature rise
The two general classifications of motor enclosures are ____and ____ open, totally enclosed
Single-phase power is usually supplied to an industrial customer False
The higher the level of the distribution voltage, the more difficult and expensive it becomes to safely insulate between line wires, as well as from line wires to ground True
The switchboard is usually supplied from the panelboard False
Movement of the coils within a transformer produces the transformation of voltage False
For an ideal transformer, the power input is equal to the power output True
The voltage ratio of a transformer is equal to its turns ratio True
If the secondary circuit of a transformer becomes overloaded, the primary circuit will not be affected False
A transformer has subtractive polarity when terminal H1 is adjacent to terminal x1 True
In a Delta-connected transformer, the phase and line voltages are equal True
Instrument transformers provide insulation between the instrument and the high voltage of the power circuit True
High voltages are used in transmission lines to reduce the transmission ____ current
For a given amount of power delivered, doubling the transmission voltage cuts the electrical loses by ___ 75%
A unit substation of a building contains high-voltage switch gear, low voltage distribution devices, transformer
Conduit conductor capacity is generally based on a ___ fill ratio 40%
The transformer winding coil that delivers power to the load is known as the ___ coil secondary
The principle of operation of a transformer is based on ___ induction mutual
The efficiency of a transformer is typically in the ___ range 90%
The low-voltage windings leads on a single-phase transformer are marked X1 and X2
Three-phase transformers are normally connected in ___ or ___ Wye Delta
If the phase-to-neutral voltage is 120 volts in a Wye transformer system the phase-to-phase voltage would be 208v
Compared to an equivalent traditional transformer the autotransformer is lower in cost, smaller in size, lower in weight
The secondary winding of a current transformer is designed to produce a standard current of 5A
Current transformers are used to supply a small amount of current that is proportional to the main current
Created by: jairoandres90
Popular Engineering sets

 

 



Voices

Use these flashcards to help memorize information. Look at the large card and try to recall what is on the other side. Then click the card to flip it. If you knew the answer, click the green Know box. Otherwise, click the red Don't know box.

When you've placed seven or more cards in the Don't know box, click "retry" to try those cards again.

If you've accidentally put the card in the wrong box, just click on the card to take it out of the box.

You can also use your keyboard to move the cards as follows:

If you are logged in to your account, this website will remember which cards you know and don't know so that they are in the same box the next time you log in.

When you need a break, try one of the other activities listed below the flashcards like Matching, Snowman, or Hungry Bug. Although it may feel like you're playing a game, your brain is still making more connections with the information to help you out.

To see how well you know the information, try the Quiz or Test activity.

Pass complete!
"Know" box contains:
Time elapsed:
Retries:
restart all cards