Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [fan]

A device that produces air movement by way of blades or surfaces attached to a rotating motor.

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Life expectancy of fan with magnetic bearing?

I asked this on Superuser a while ago, but since fans are often used for cooling electronic devices, I think that the question would be on-topic here too. So how long is life expectancy of fan with magnetic bearing? I did some looking on catalogs of…
AndrejaKo
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Why does my 24VDC fan draw much less current than labeled?

I have three Delta PFB0824UHE, which were provided to me by a customer for a project. They are labeled 0.93A. When actually hooked up to 24V, the fan draws .45A, regardless of head pressure. This current varies linearly with input voltage, going as…
Stephen Collings
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How to read RPM from 3-wire fan - PIC18F4550

I am working a PIC µC project. I am using 12VDC PC fan (Coolermaster) for my application. A part of the project is to return the RPM from the third wire of the fan to an LCD. First of all, How can I read the signal? Is it a sort of pulses every…
Mohammed Nafie
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Why do fans keep running after power-off

What is the reason why the fan of many electronic devices, such as video projectors, laser printers or kitchen ovens (have to) continue running after the device has been powered off? It is my understanding that fans are required to bring fresh air…
Michael Schmid
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Furnace operated ceiling fan

I was thinking of having a ceiling fan come on when my furnace came on. I used to dabble in electronics but it's been a long while and I know there are new and innovative approaches to accomplish the task. But, I'm kind of out of date on ideas. Does…
Norman Sobieck
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How to slow down 240V AC bathroom fan

I have a small toilet fan which is quite noisy and far too powerful for what we need. I'm looking for a solution where I could reduce AC 240V to AC 110-150V with minimum amount of components. Any transformer is out of question. Simply, no room for…
Artur Adam 70
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Ceiling fan speed controller question

I need to connect 15 ceiling fans. Each bay has 3 ceiling fans that will run of the same speed controller, so 5 controllers in total. They will be wired from a separate circuit from the DB box. Here's the schematic below that I drew up: Since each…
Deadshot
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Running a 12V PWM Water pump on a 5V fan output with tacho input

So on my 3D printer from Prusa they use 5V fans and monitor the fans by the tacho signal. I want to replace the hotend with a water cooled version and still want to have the safety feature to turn off the hotend heater when the fan is not running.…
Empusas
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Can I have two regulator for wall fan - one default one and second I externally connect at switch board

I have bought one wall fan with following specification: Fan speed: 1900 RPM Voltage: 220-240 V Frequency: 50 Hz Power: 125 W It has inbuilt step type regulator with 3 stage button to either slower or faster the fan speed viz., 1=slow, 2=Medium,…
user3099630
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Connecting a computer fan controller for multiple 12V DC fans to 120V AC

I would be interested to control multiple fans in an application that is outside a computer. I didn't find any interesting product for controlling multiple 12V 120mm fans that I could connect to 120V with an adapter. So my question is: if I'm going…
m_power
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Description of signals in Laptop Fans

My laptop has this fan, which I want to replace. But before blindly replacing it and make it work I am curious to know what all signals are associated the four wires: Black, Pink, Yellow & Red. I could not find a technical specification for this…
gpuguy
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How to determine the number of windings needed for a ceiling fan rotor?

I have picked up from the trash, three oldish ceiling fans. They do not run on electronics. Upon opening the rotor, I can see two coils; one outer and one inner. They look real dirty and I would like to learn to clean them up and replace the…
extensa5620
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How do I make a low-noise computer case fan adaptor cable (using a resistor)?

I have a Noctua NF-12x25 5V fan, used in a custom Raspberry Pi case, that's a bit too loud for my taste. Noctua sells low-noise adaptor cables for 12V their fans that, from what I understand, are just cables with an in-line resistor. I know almost…
tibbe
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Fan airflow direction conventions

What are the conventions for the direction of air flow for a fan? To state the question a different way, how can I determine the direction of air flow without actually applying a voltage to the fan? For instance, here's an image of a 24V DC…
MattHusz
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Why is a 12V 3-wire CPU fan very slow at 12V input?

I play around with an old 3-wire CPU fan from a dell server PC. It is this thing: 3612KL-04W-B66 https://www.coolingsurplus.com/index.php?option=com_content&view=article&id=86:3612kl-04w-b66&catid=6:92mm-fans&Itemid=7 It was mounted at the end of…
Artur Cichosz
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