Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [electromagnet]

78 questions
26
votes
5 answers

Help with homemade electromagnet

Just for fun, I decided to build what I was hoping would be a relatively powerful electromagnet. I used this copper wire (20 AWG, entire 1 pound spool) and this soft iron core (0.5 in diameter, 6 in length). The total length of the wire is…
x7benihana
  • 261
  • 3
  • 5
20
votes
3 answers

How critical is winding a solenoid/electromagnet neatly?

We've all seen the expensive toroidal winding machines on YouTube, and manufactured solenoids are always so neat in construction - as in: Each winding is neatly packed to its previous, without overlapping itself: like "-/////////-" There's no…
Litch
  • 311
  • 2
  • 5
11
votes
1 answer

Why do I need to remove a part of the insulation on a copper wire on a simple electric motor?

Why do I need to remove a part of the insulation on one end of a copper wire in making a simple coil electric motor? How does removing only a part of the insulator makes the motor spin freely? Reference at step 3. I know why the coil spins. What I'm…
Satou Kazuma
  • 157
  • 1
  • 6
8
votes
5 answers

How do I build an electromagnet?

I want to make an electromagnet that can lift a paper clip off of the ground from a short distance (probably 7 to 8 inches). I naively thought of making an electromagnet as a simple task (because of the short videos which make it seem so simple),…
Will
  • 99
  • 1
  • 4
4
votes
2 answers

LEDs keep dying in 12v circuit with powerful electromagnet

I have a circuit like this: 12V/2A DC input. A small blue LED with a 2.2k resistor in series. A powerful electromagnet with ~40ohm resistance in parallel. It is possible the electromagnet has more components on the inside. When I turn the switch on…
Ants Aus
  • 75
  • 4
3
votes
3 answers

How can I control five hundred 250 mA electromagnets with shift registers and MOSFETs at the same time?

At the moment I control 16 electromagnets. I will later daisy chain the shift register control boards to control 500 electromagnets 250 mA each at 24 V (could be 12 V) with shift registers and MOSFETs at the same time but the current consumption is…
Mastalyn
  • 31
  • 1
3
votes
3 answers

What happens if the secondary of an ordinary transformer is left open?

Let's consider a transformer. The ideal transformer equation is: $$\frac{V_1}{V_2} = \frac{I_2}{I_1}$$ Suppose the secondary is open (that means \$I_2 = 0\$): it will result \$I_1 = 0\$. How is this physically possible? I'd say that, also in case of…
Kinka-Byo
  • 3,340
  • 2
  • 19
  • 58
3
votes
5 answers

Making a electromagnet

Can an insulated wire be used to make a electromagnet? Will there be any difference in strength of the magnet if I use an uninsulated wire instead? By uninsulated wire I mean this:
user29463
  • 105
  • 1
  • 6
3
votes
2 answers

Electromagnetic crane

I want to make a strong electromagnetic crane that would carry weights from one position to another. I am very unsure about the material. Do I use an old transformer? or What type of rods? What type of wire? Also, how can I make sure there is no…
Sarah Jamal
  • 41
  • 4
2
votes
2 answers

H-Bridge Circuit w/ Inductor Demagnetization

I'm building an H-bridge circuit designed to send a pulse through an electromagnet, and then rapidly collapse the field of the electromagnet coil as soon as the transistors switch off. Minimizing the field collapse time is a critical parameter to…
Flywheel
  • 21
  • 3
2
votes
1 answer

How do I make an electromagnet that weighs less than 2 kg but can exert a force of at least 420 N

For a project that I am doing currently I will need an electromagnet whose total weight is less than 2kg, but can exert a force of at least 420 N on a ferromagnetic material 0.03 m (3 cm) away from the electromagnet. The force is going to…
Sreenandan Balasubramaniam
  • 53
  • 6
2
votes
5 answers

Reducing Residual Magnetism in Electromagnets

My issue is that after the electromagnet has been switched off, the magnet and the test steel C45 object attracted to it remain attached. The residual force appears minimal, as no object which was not previously in contact can stick to the magnet,…
Rexcirus
  • 133
  • 8
2
votes
4 answers

MOSFET Drain - Source Current limiting

I am a new enthusiast to MOSFETS. I am trying to use a MOSFET to switch on and off a electromagnet that draws 5 amps at 1.2 volts using an Arduino. The circuit I am using has a diode going from the negative to the positive terminal of the…
Will
  • 29
  • 1
1
vote
0 answers

Mixing power supplies with inductive loads

I have two unregulated power supply - 24V and 12V. My board consists of digital components and sensors that require 3.3V or 5V. All that electronics is resposible for electromagnets or DC brush motors control and PC communication. Electromagnets'…
pajur97
  • 11
  • 2
1
vote
1 answer

Wrong orientation of a diode destroy a circuit (Schematic included)

I get 24V from the barrel jack. The electromagnet is controlled using PWM. Here, I made a mistake and the diode direction is reversed. (The diode is placed to protect from back EMF.) When I plugged in the power it maded a sound and the power…
thankyounaly
  • 119
  • 7
1
2 3 4 5 6