Download bridge rectifier to use.

Datum: 25. 3. 2012
Projekt OBOGATENO UČENJE TUJIH JEZIKOV
Primer PRIPRAVE NA POUK tujega jezika za mesec MAREC 2012
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Srednja šola tehniških strok Šiška
partneska šola
Gradivo za elektrotehniko
ANGLEŠČINA
Operacijo delno financira Evropska unija iz Evropskega socialnega sklada ter Ministrstvo za šolstvo in šport. Operacija se izvaja v okviru Operativnega programa razvoja človeških virov v obdobju 2007-2013,
razvojne prioritete: Razvoj človeških virov in vseživljenjsko učenje; prednostne usmeritve: Izboljšanje kakovosti in učinkovitosti sistemov izobraževanja in usposabljanja.
BASIC ELECTRONICS BRIDGE RECTIFIER
I. WATCH THE VIDEO
Basic Electronics Bridge Rectifier tutorial: http://www.youtube.com/watch?v=1pwBmGy9sz0, 6.54
http://xcircuit.sourceforge.net/tutorial/tutorial2.html
http://www.tradenote.net/keyword/KBPC
II. TRANSLATE THE KEY WORDS FROM THE VIDEO INTO SLOVENE.
1. bread board
2. transformer
3. output
4. input
5. coil
6. led, light emitting diode
7. capacitor
8. resistor
9. circuit
10. bend* (bend-bent-bent)
11. silver strip
12. junction
13. AC, alternating current
14. DC, direct current
15. positive terminal
16. blank
17. jumper
19. mains
20. supply
21. discharging
III. WHAT IS A RECTIFIER? FILL IN THE GAPS:
A rectifier is an electrical device that converts ___________________ (AC), which
periodically reverses direction, to ____________________ (DC), which is in only one
direction, a process known as ________________________.
A device which performs the opposite function (converting DC to AC) is known as an
___________.
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RECTIFIER, USMERNIK
IV. Complete the crossword with the help of the words from the video.
Half-wave rectifier application: Two level lamp dimmer.
http://www.allaboutcircuits.com/vol_3/chpt_3/4.html
Across
Down
4. spoj
9. usmerjanje
13. razelektritev
14. trak
15. izmenični tok
16. omrežje
18. usmerjati,usmeriti(el.tok)
20. svetleča dioda
1. zviti,2.obl.glagola
2. upor
3. kondenzator
5. pol,priključek
6. izhod
7. vhod
8. prazen
10. mostiček, povezava, prevezava
11. vezje
12. enosmerni tok
17. oskrba,napajanje,dobava
19. tuljava
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THE USE OF BRIDGE RECTIFIERS
V. TRY TO ANSWER THE QUESTIONS AND THEN CHECK YOUR ANSWERS IN
THE FOLLOWING TEXT.
1. Bridge rectifiers were developed about ___________ years ago.
2. They are used for powering our _______________________________________________.
3. They take household current and change it into a more _____________________________.
4. The reasons we have bridge rectifiers is the need for
_______________________________.
5. Direct currrent runs most of our _______________________________________________.
6. In a power supply, the rectifier is situated between a _____________________ and a set of
__________________.
7. The transformer drops the 110-volt household current down to ______________________,
usually between 3 and _________volts, depending on the appliance.
8. This lower voltage, still A.C., is changed to D.C. by ______________________________.
9. The bridge rectifier, necessary for a strong, reliable supply of D.C. power, was an
essential part of the ________________ revolution.
10. ________________and _______________ are prime concerns for
choosing the kind of
bridge rectifier to use.
THE KEY WORD
Unscramble the tiles to reveal a message.
Created by Puzzlemaker at DiscoveryEducation.com
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WHAT IS A BRIDGE RECTIFIER USED FOR?
By J T Barett, Bachelor of Science in physics, eHow Contributor (adapted)
http://www.ehow.com/about_5048018_bridge-rectifier-used.html
Bridge rectifiers, developed about 100 years ago, are an essential part of powering our
electronic appliances. They take household current and change it to a more useful form.
Having that fundamental ability has given us stereos, computers, television and radio, as well
as powerful commercial and industrial equipment.
DIRECT CURRENT
The reason we have bridge rectifiers is the need for D.C., or direct current. Direct current runs
most of our home electronics. While it can be supplied by batteries, they have limited lifespan
and power. It's better in many instances to have a strong, continuous source of D.C. We can
get power from the household electrical outlet, but that's A.C., or alternating current.
Fortunately, there's a way to change A.C. into D.C., and that's by using a power supply with a
bridge rectifier.
CIRCUITRY
In a power supply, the rectifier is situated between a transformer and a set of capacitors. The
transformer drops the 110-volt household current down to a safe and useful level, usually
between 3 and 24 volts, depending on the appliance. This lower voltage, still A.C., is changed
to D.C. by the bridge rectifier.
The D.C. coming out of the rectifier is noisy and imprecise. For some uses, like a battery
charger, this rough D.C. is adequate. For others, like running a stereo, the noise needs to be
removed. The power is filtered by the capacitors and held to a fixed level by a regulator.
BENEFITS
The bridge rectifier, necessary for a strong, reliable supply of D.C. power, was an essential
part of the electronics revolution, from radio and television to stereos, cell phones, and
computers. Though batteries filled this need to some extent, they also added size and weight
to electronic gear. Reducing or eliminating the need for batteries made equipment smaller,
lighter, and more reliable.
CONSIDERATIONS
Current and voltage are prime concerns for choosing the kind of bridge rectifier to use. The
smallest can be used to power cell phones and mp3 players. These are a few millimeters on a
side with modest cooling requirements. Larger items like stereos need a bigger rectifier,
possibly with a heat sink. Commercial and industrial systems like telecommunications
equipment need even more power, calling for larger or multiple rectifiers with forced-air
cooling.
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