Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [solenoid]

An electromagnet combined with an actuator to convert electrical energy into linear physical motion.

601 questions
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Why aren't solenoid/electromagnet windings insulated?

This has been bugging me for a long time. Take this video for example. I have always thought that electricity will take the shortest path. When the electromagnet's windings are uninsulated, it seems that the electricity would flow straight through…
Joel
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Why did my fuse blow after 3+ years of no problems?

For several years, I've had a solenoid wired to the 24VDC output of a PLC (Rockewell Automation 1769-OB16). To protect the PLC output card, a fast-acting 500mA fuse was installed between the PLC and the solenoid. The fuse has been working without…
CaptJak
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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
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How to properly wind coils for a solenoid?

I need to wind a small electromagnet "solenoid?". About 3cm high and 2~5cm wide running at 5V/0.5A. This magnet will be put into a desk bell so it pulls the clapper down and rings the bell. I have found ready made solenoids that push out but not…
Piotr Kula
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My MOSFET operated solenoid circuit destroys my Arduino inputs

I made a series of PCBs to power some solenoid valves that use an external power supply. I switch them with BS170 MOSFETs using an Arduino as gate signal. I based it a solution by Jason S. This is an illustration of what my circuit looks like: On…
Dyte
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Electrocuting a fruit fly using magnetic induction

We are electrically inducing heart attacks in fruit flies to test the effects of various treatments on survival. We are shooting for roughly a 50% survival recovery rate in our control group. I work with a lab that is studying cardiac function in…
user146252
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MOSFET broke after attaching capacitor bank

I have a solenoid that has a coil resistance of \$0.3\Omega\$ and accelerates a steel projectile here. I've posted the schematics below. Normal Version that acts as a control The GPIO8 goes to 5V to switch on the MOSFET and turn it off when the…
user229515
11
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1 answer

Is there such a thing as an ultra low power solenoid?

I am looking for a tiny push-type solenoid that can be driven with milliwatts. The plunger need only move 2-3 mm. Does such a thing exist?
augustzf
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Do solenoids exhibit back EMF like motors?

I just purchased some pinball machine solenoids and was experimenting with them; DC resistance is about 30 ohm, they actuate at about 30 volts, and they hold at about 6. I tried controlling them with 10A relays and found that the a relay sometimes…
supercat
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Measuring the activation time of a solenoid

I'm trying to measure the activation time of a pull-type solenoid. When the solenoid doesn't have a load connected to it, you can measure its activation time through the current it consumes. At first, the solenoid will consume current until the…
Florian Humblot
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2 answers

Electrical behavior of holding magnets when you pull them apart

I'm going to buy a holding electromagnet and a strike plate to hold some things, and I want to design my circuit (arduino-controlled) not to fry like bacon. I'm aware that since a holding magnet is an inductor, I should use a flyback diode and…
Ed Krohne
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Can Solenoids Get Sticky From Improper Usage?

I bought three spring-return, push-type solenoid. I can't remember them being sticky from the start because I only was using one at a time, but they may have been. Now that I tried to work them together, two are so sticky that they have become…
Andrew Spitz
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Why is this reed switch / solenoid circuit not working?

The (normally open) reed switch should close by waving a magnet across it, completing the circuit. The 6v solenoid lock should pull inwards allowing the door to be opened. When the magnet is removed the reed switch should open. So my issue is the…
Dominic Edwards
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changing direction of solenoid

note I know essentially nothing about solenoids I brought this solenoid thinking that I could use it to hit an object, but when I put it to a power supply, the only direction that it would go is down. I tried changing the direction of the current…
manoli
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How to decrease solenoid speed?

My project concerns speed control of a solenoid. In this project, the stroke is 30 mm. I want the plunger to cross 30mm in a few seconds (like 5 seconds).) For this purpose I want to control the current of the solenoid coil with PWM, but it seems…
farshid
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