Developing Electrical Troubleshooting TPC
Exam|95 Questions with Answers
The actual location and routing of circuits is shown on a - -wiring diagram
- A power-installation drawing shows - -only power outlets
- Changing the number of magnetic poles in the stator of a squirrel-cage
motor permits the motor to run - -two or more fixed speeds
- Most reversing starters with low-voltage remote pushbuttons are all of the
following EXCEPT - -mechanically interconnected
- Deterioration in a selenium rectifier is indicated by - -a gradual rise in the
input current
- In autotransformer input circuits, each input line should be - -fused
- Which of the following is NOT a common cause of mechanical vibration? - -
Worn brushes
- All of the following are common reasons why a split-phase motor makes a
noticeable noise when operating, EXCEPT - -too little end play
- On an electrical diagram, a control relay is indicated by the designation - -
CR
- The ____________ circuit of an electrical schematic is the simplest part of the
diagram and the easiest to follow. - -power
- Mixing brush grades in a dc motor causes - -unequal load distribution
among brushes
- A film of oil on the commutator does all of the following EXCEPT - -prolong
brush life
- Overvoltage, excessive current and too-frequent operation are possible
causes of - -burned or short-circuited magnet coils
- A relay that has "dogs" located directly above the operating bar is called a
____________ relay - -latching
- Which are most affected by overvoltage? - -Slow-speed motors(not sure)
, - If a motor stops for no apparent reason and you are called to inspect the
motor starter, the first thing you should check is the - -trip levers on the
thermal overload relays
- NEMA recommends seasoning linear lamps for _____ hr before dimming - -
12
- The color temperature of the light produced by a lamp is expressed in
degrees - -Kelvin
- Mechanical linkages of motor contacts, relays, and solenoids on new
equipment should - -move freely when the machine is turned on
- In the identification 8TR15XTO, the X indicates - -normally closed
- Thermal overload relays can generally be reset after cooling for about - -1
minute
- One added feature of newer motor starters is a single-phase sensor that
detects - -current unbalance
- A circuit that provides undervoltage release and has two wires connected
to the pilot device that energizes the magnetic control circuit is said to have
- -two-wire control
- The ____________ contacts on a motor starter provide a parallel path for the
current to the coil - -auxiliary
- Most methods of reducing motor speed when using multispeed controllers
involve the operator - -pressing the STOP button
- Operating a heavily loaded motor at __________ can cause a high slip - -
reduced voltage
- Adding limit switches to the control circuit of a reversing motor provides -
-overtravel protection
- On a reversing starter, mechanical interlocks are used to prevent both sets
of three-phase contacts from being operated at the same time. The closing
of ____________ operates a mechanism that prevents the closing of the
opposite contactor. - -one contactor
- Which of the following is not typically used to identify conductors in a
motor-control circuit? - -Colors
Exam|95 Questions with Answers
The actual location and routing of circuits is shown on a - -wiring diagram
- A power-installation drawing shows - -only power outlets
- Changing the number of magnetic poles in the stator of a squirrel-cage
motor permits the motor to run - -two or more fixed speeds
- Most reversing starters with low-voltage remote pushbuttons are all of the
following EXCEPT - -mechanically interconnected
- Deterioration in a selenium rectifier is indicated by - -a gradual rise in the
input current
- In autotransformer input circuits, each input line should be - -fused
- Which of the following is NOT a common cause of mechanical vibration? - -
Worn brushes
- All of the following are common reasons why a split-phase motor makes a
noticeable noise when operating, EXCEPT - -too little end play
- On an electrical diagram, a control relay is indicated by the designation - -
CR
- The ____________ circuit of an electrical schematic is the simplest part of the
diagram and the easiest to follow. - -power
- Mixing brush grades in a dc motor causes - -unequal load distribution
among brushes
- A film of oil on the commutator does all of the following EXCEPT - -prolong
brush life
- Overvoltage, excessive current and too-frequent operation are possible
causes of - -burned or short-circuited magnet coils
- A relay that has "dogs" located directly above the operating bar is called a
____________ relay - -latching
- Which are most affected by overvoltage? - -Slow-speed motors(not sure)
, - If a motor stops for no apparent reason and you are called to inspect the
motor starter, the first thing you should check is the - -trip levers on the
thermal overload relays
- NEMA recommends seasoning linear lamps for _____ hr before dimming - -
12
- The color temperature of the light produced by a lamp is expressed in
degrees - -Kelvin
- Mechanical linkages of motor contacts, relays, and solenoids on new
equipment should - -move freely when the machine is turned on
- In the identification 8TR15XTO, the X indicates - -normally closed
- Thermal overload relays can generally be reset after cooling for about - -1
minute
- One added feature of newer motor starters is a single-phase sensor that
detects - -current unbalance
- A circuit that provides undervoltage release and has two wires connected
to the pilot device that energizes the magnetic control circuit is said to have
- -two-wire control
- The ____________ contacts on a motor starter provide a parallel path for the
current to the coil - -auxiliary
- Most methods of reducing motor speed when using multispeed controllers
involve the operator - -pressing the STOP button
- Operating a heavily loaded motor at __________ can cause a high slip - -
reduced voltage
- Adding limit switches to the control circuit of a reversing motor provides -
-overtravel protection
- On a reversing starter, mechanical interlocks are used to prevent both sets
of three-phase contacts from being operated at the same time. The closing
of ____________ operates a mechanism that prevents the closing of the
opposite contactor. - -one contactor
- Which of the following is not typically used to identify conductors in a
motor-control circuit? - -Colors
