Reactors and Isolation Transformers
Help!
|
|
||||
|---|---|---|---|---|---|
| 1. A __ is a distortion in a voltage waveform where the voltage quickly drops toward zero and then returns to the correct value( Choke; Notch; Relay; Switch) | Notch
🗑
|
||||
| 2. __ is the opposition to current flow in an AC circuit. (Choking; Impedance; Reactance; Shielding) | Reactance
🗑
|
||||
| 3. A __ is an inductor whose inductance is controlled through the use of a magnetic field created by a second winding wound around the same iron core as the primary winding. (Next Card) |
🗑
|
||||
| (Common-mode choke; Drive isolation transformer; Saturable-core reactor; Silicon-controlled rectifier) | saturable-core reactor
🗑
|
||||
| 4. Electric motors typically draw many times their full-load current during startup. T/F | True
🗑
|
||||
| 5. A reactor should have about __ impedance to reduce notch depth by about 50% (3%; 5%; 10%; 12%) | 3%
🗑
|
||||
| 6. All two-winding transformers are isolation transformers. T/F | True
🗑
|
||||
| 7. __ is a type of electromagnetic interference induced on power or communication lines ( Common-mode noise; Notching; Resonance; Zero-switching) | Common-mode noise
🗑
|
||||
| 8. A __ is a reactor used to reduce common-mode noise current generated by the rapid switching of a motor drive or a signaling device . ( next card) | Common-mode choke
🗑
|
||||
| (Capacitor bank; Common-mode choke; Isolation transformer; Silicon-controlled rectifier) | Common-mode choke
🗑
|
||||
| 9. In a saturable-core reactor, large amounts of DC current can be controlled by a small amount of AC current. T/F | False
🗑
|
||||
| 10. Zero-crossover are often used for timing signals and to activate equipment T/F | True
🗑
|
||||
| 11. With a variable-frequency drive, unwanted pulses of current are caused by fast-changing voltages from the drive T/F | True
🗑
|
||||
| 12. Explain the formation of voltage notches when using SCRs | Two SCR are fired at the same time
🗑
|
||||
| 13.Explain the rationale for reducing notch depth by 50% . Why not more? Or less? |
🗑
|
||||
| 14. A saturable-core reactor consists of one winding T/F | False
🗑
|
||||
| 15. Electrostatic shields can prevent common-mode noise from transferring from the transformer's primary to the secondary only if the secondary is grounded T/F | False; secondary ungrounded
🗑
|
||||
| 16. __ help eliminate voltage spikes by slowing down the rate of change in the drive output voltage. ( Drive isolation transformers; Output reactors; Output rectifiers; Variable-frequency drives) | Output reactors
🗑
|
||||
| 17. To reduce notching, a reactor can be used to add impedance. the added impedance__ (next card_ |
🗑
|
||||
| (Decreases notch depth & narrows notch width; | Decreases notch depth and widens notch width
🗑
|
||||
| 18. List the three basic functions of a drive isolation transformer | page 148
🗑
|
||||
| 19. A __ is a reactor used to restrict the current to AC or DC drives in the case of short circuits in the drive itself | Choke
🗑
|
||||
| 20. A drive isolation transformer is designed with additional __ to reduce power quality problems associated with nonlinear loads ( flux; reactance; resonance; shielding) | reactance
🗑
|
||||
| 21. List 3 benefits associated with grounding the secondary of a drive isolation transformer | p 149
🗑
|
||||
| 22. The secondary of a drive isolation transformer represents a separately derived system T/F | True
🗑
|
||||
| 23. List 3 uses for line input reactors | p 141
🗑
|
||||
| 24. Nonlinear rectified power supplies are a common cause of power quality problems T/F | True
🗑
|
||||
| 25. A ___ is a coil added in series with a load to reduce inrush current, voltage notching effects, and voltage spikes ( capacitor; plolarized-frequency relay; reactor; silicon-controlled rectifier_ | Reactor
🗑
|
||||
| 26. Rectifiers are ;used in the starters of large synchronous motors to provide a voltage to the AC coil of the polarized-frequency relay T/F | False
🗑
|
||||
| 27. HOw are drive isolation transformers and line reactors similar? Which can provide additional benefits, and what are they? | p 150
🗑
|
||||
| 28.Match the picture p 105 |
🗑
|
Review the information in the table. When you are ready to quiz yourself you can hide individual columns or the entire table. Then you can click on the empty cells to reveal the answer. Try to recall what will be displayed before clicking the empty cell.
To hide a column, click on the column name.
To hide the entire table, click on the "Hide All" button.
You may also shuffle the rows of the table by clicking on the "Shuffle" button.
Or sort by any of the columns using the down arrow next to any column heading.
If you know all the data on any row, you can temporarily remove it by tapping the trash can to the right of the row.
To hide a column, click on the column name.
To hide the entire table, click on the "Hide All" button.
You may also shuffle the rows of the table by clicking on the "Shuffle" button.
Or sort by any of the columns using the down arrow next to any column heading.
If you know all the data on any row, you can temporarily remove it by tapping the trash can to the right of the row.
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
Normal Size Small Size show me how
Created by:
JoshHampton