Exp. #6: Flyback Diodes

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rjagodowski
Posts: 1782
Joined: Fri Sep 04, 2015 6:59 pm

Exp. #6: Flyback Diodes

Post by rjagodowski »

This week's experiment investigates the action of flyback diodes. A pdf of the assignment is attached below. A printed copy will be provided for you in lab.

Flyback diodes are used with inductive elements, usually placed directly in parallel with them, to reduce the back emf induced across the coil when the current through the coil is interrupted. In this experiment, you should see back emf voltages in the 150V to 300V range, possibly higher. When the diode is placed in parallel with the coil it is installed such that it is reverse biased in relation to the polarity on the coil when it is energized. That is, during regular operating, it looks like an open circuit and has no effect on circuit operation. The current through the coil will create a magnetic field around the coil. (For the relay used in this experiment it's that very magnetic field that is switching the contacts on the output of the relay. But ALL coils will have this similar action. Inductors, relay coils, motors, ignition coils, solenoids, speakers...anything with a coil.) However, when the coil through the current is interrupted, a very brief voltage spike will appear across the inductor as the collapsing magnetic field cuts the windings in the coil. with the polarity which forward biases the diode. The forward voltage drop across this diode will limit the back emf to somewhere in the neighborhood of 2-5 Volts. The 0.7 volts usually attributed to a standard silicon diode will be a bit greater than that due to the high voltage and high instantaneous current through the diode.

Read the attached document carefully. Your completed lab report is due on or before 5:00 PM on Thursday, April 8, 2021 for those in the Thursday (-D02) lab section. The due date is on or before 5:00 PM on Tuesday, April 13, 2021 for those in the Tuesday (-D01) lab section.


Flyback Diode Experiment v21.1.pdf
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noong0001
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Joined: Fri Sep 06, 2019 9:52 am

Re: Exp. #6: Flyback Diodes

Post by noong0001 »

FLYBACK DIODE
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noong0001
Posts: 41
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Re: Exp. #6: Flyback Diodes

Post by noong0001 »

FLYBACK DIODE
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samohamed0001
Posts: 49
Joined: Tue Sep 18, 2018 6:10 pm

Re: Exp. #6: Flyback Diodes

Post by samohamed0001 »

no flyback diode and flyback doide
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samohamed0001
Posts: 49
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Re: Exp. #6: Flyback Diodes

Post by samohamed0001 »

flydoide
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bking0001
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Joined: Fri Sep 06, 2019 9:44 am

fly back diodes

Post by bking0001 »

this is chart
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noong0001
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Re: Exp. #6: Flyback Diodes

Post by noong0001 »

Naing Ong-Flyback Diode.pdf
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jcolon0004
Posts: 31
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Re: Exp. #6: Flyback Diodes

Post by jcolon0004 »

Flyback diode
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mmlopez0002
Posts: 40
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Re: Exp. #6: Flyback Diodes

Post by mmlopez0002 »

mmlopez0002
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hbonney0001
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Re: Exp. #6: Flyback Diodes

Post by hbonney0001 »

WK 6 FLYBACK WITH NAI BH
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ljwalsh0001
Posts: 28
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Re: Exp. #6: Flyback Diodes

Post by ljwalsh0001 »

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