Search for RPM in Topics



Air Compressor RPM? Answered

I found an old cast iron 50 + year old 2 stage air compressor and I was wondering what RPM's I should run it at.  My dad says it is running much slower than he remembered and it is going 323 RPM's compared to the original gear ratio that would have run at 269 RPM's.  That should be dramatically faster, so could going too fast decrease performance, or something, or is there a reason the original motor may have slowed down? The RPM's are a complete guess based upon the 1725 RPM motor average.  The only reason I had to change pullies was because the original had FLAT BELTS (awesome) from back when people cared and build stuff right.  Now I have a v-belt on it and the compressor pulley wobbles by like 2 inches and the thing is out of line, but these shouldn't be slowing it down. Basically I need to know what RPM's I should be running the compressor at. P.S.  It can double as a vacuum  pump and it uses old fashion check valves!

Question by jj.inc    |  last reply


RPM of K'nex engines? Answered

Does anyone know the revolutions per minute for the K'nex electric motor (grey one with mains adapter) and the revolutions per minute for the K'nex tethered battery motor (same as standard battery motor I think). Electric one is first picture, battery one is second picture.

Question by The One and Only    |  last reply


RPM/MPH formula

I'm designing an anemometer with Arduino and I need a formula to figure out the speed at which the rotor turns. I have a rotor with three magnets, spaced 71mm apart, triggering a Hall Effect sensor which the Arduino reads and counts. Now I can't seem to figure out a formula to calculate wind speed from this information. Anybody got an Idea (or the answer?)

Topic by smkoberg    |  last reply


Has anyone Hacked the," Nsd Power Ball Sm-01 Speedometer ?

Has anyone Hacked the," Nsd Power Ball Sm-01 Speedometer ? The Sm-01 ( the speedometer of Nsd power Ball ) Functions are: a. the count of revolutions ( hundred unit ) b. the current RPM c. the historical highest RPM/ the current highest RPM d. the physical index, 30 sec., 60 sec., 90 sec. The above-mentioned functions work individually. The speedometer can make users understand the use state of PB and provide real figures for reference. It combines the effects of rehabilitation, entertainment, and contest. Can anyone explain how this speedometer works. Is it Optical ? Since the Power Ball has 5 LED's incorporated in the Gyro Ball does this trigger the output ? Or is it magnetic ? When I, place compass next to the Power Ball the compass dial spins like a motor. How can I, use this speedometer to registered the speed or RPM of wheel ? Looking forward to hearing any suggestions, on how I may HACK this Great Speedometer/ TACH . This speedometer can be found on eBay for about $15.00 it's small and compact. It surprises me that no one has Hacked this for other uses !

Question by MagicLanternProductions    |  last reply


how to run a high voltage motor with low voltage Answered

Hi there, I just wanna know how to run a 12v D.C motor using a 9v battery, is it possible by using  voltage and current doubler circuits? please help me, as i want this knowledge for a project of mine

Question by VivekM12    |  last reply


General question about controlling car engine ??? Answered

Hi ... I would like to ask, how do call the "thing" that control RPM of your engine ??? What I mean ... there is something - kind of small motor, that controls the RPM. When you start your engine and you don't have any gear it holds the RPM on cca 1000 RPM. But in winter (when the engine is cold) it brings the RPM to 1500 ... and then, when the engine becomes warmer, it decreases the RPM. 1. How do you call the part, that controls these RPM ??? 2. Is there any restriction that says what is the maximum RPM that this "small motor" can provide... like it will not make more then 2000RPM ... or you could set it up up to 7000RPM as well ??? Thank you in advance...

Question by zholy    |  last reply


Slow down a DC motor?

Here is another basic electronics question for all of you: What is the easiest way to slow down the RPM of a small DC motor? Much appreciated!

Question by brandegor    |  last reply


Hows this circuit as mileage meter? Answered

I recently got permission from my parents to hack the car,so I thought,what mod is most suitable in India.so I came up with an idea of milage meter My dad told me that the amount of petrol used in each cycle of engine is the same,adjusted to optimum level. So I thought that if i can divide the rpm value with speed,i'll get rounds per distance,ie fuel consumption per distance. and i devised the following circuit for it-

Question by Suraj Grewal    |  last reply


Create standstill effect with LED from hall effect sensor ?

Hi everyone, A little bit info of what I'm working on. I am trying to create a standstill effect of the spokes of the car rim. I attached a hall effect sensor and a magnet to inside of the rim . I have tried 2 different approaches : ( code for each method are also attached)              1. use the hall effect sensor to determine the RPM of the rim and then flash the led accordingly to the spokes on the rim. The problem with this approach is that the led flash quite dim and and the spoke image rift.  I cant find the right windows for flashing LED.               2. use the the hall effect sensor to detect any magnetic field and then flash whenever it is detected. This method is quite simple but the effect is blurry. The problem for this is that the magnet detection happen on the arc of the rim instead of at 1 pin point location. Hence the led is on for too long --> blurry effect. I also attache some diagram to explain my problem in case I didn't do well with words.  Do you have any suggestion, solution or comment on the approaches or the code. Please feel free to throw in. Im all ear.  Code:  Method 1: Calculating RPM then flash led : http://txt.do/5b9is I am leaning toward this method but the effect is rifting. Not entirely sure how to fix it or what could possibly cause it.  to clarify: the rifting effect happen when i use 2 magnets on the rim. with only 1 magnet, it still rift but the led very dim, almost unnoticeable.  Method 2:  Image for the 2nd approach in case the pictures didnt show on instructables the front : http://imgur.com/HwFm1lT the back : http://imgur.com/1DvWjZK the side : http://imgur.com/RHZIbfR The problem : http://imgur.com/RHZIbfR flashing LED whenever sensor detect the magnet: http://txt.do/5b9b7

Question by Jack Vu    |  last reply


50k RPM with DIY Motor?

Has anyone built an electric motor that can reach 30-50k RPM? Would you think it is possible to build one?

Topic by Tyoon    |  last reply


Arduino LDR tachometer (RPM counter)- not sensitive enough ?!?

Ladies & Gentlemans  ... I would like to ask you, what I'm doing wrong, in this RPM counter ??? As mentioned in my previous questions, I 've got an ARDUINO and I started with my first part - of my project. To count RPM / or speed. I'm using a LDR (light dependant resistor) and green laser as light source. The scheme is like this: + 5V ------- LDR -------------Analog pin 1                                     \                                       \--------resistor (220kOhm) --------- GND The code for this project looks like this : int LDR=1; // LDR is on analog port 1 int val=0; // this is the value, I get from the LRD void sextup(){  Serial.begin(9600); } void loop() {  val = analogRead(LDR); // read the value getting from LDR Serial.println(val); if (val<1018) {delay(4000);} } To explain the value 1018 in the IF condition ... when pointed the laser on the LDR,I get value from 1019-1020. So my idea was, when the value decrease just by one or more ... let me know, that the laser beam has been interrupt. But I realised, that I can cross the laser beam very quickly, and the LDR/Arduino will not notice it. I really don't know, where I'm going wrong. My few suggestions are : 1. wrong method - to use LDR ... should I use something else ??? 2. wrong RESISTOR value ??? ... should I change to different value to make it more sensitive ??? (I tried 2 different values = 220kOhm, 46kOhm ... that's what my voltmeter said :) ... but with both of them I have the same result ) 3. should I use different code ??? Any ideas ??? Thank you in advance for your answers. Zholy

Question by zholy    |  last reply


How can I use this router bit? Answered

I recently purchased a big 2 HP router and a 15 bit set from Harbor Freight. The router is going on the finished CNC router, but I also needed it to make a few chamfers on the sides of some of the parts. The router is one speed, and says that it has a "Maximum RPM of 29000". The chamfer bit that came with the set, on the other hand, says that it has a max speed of 18000. What do I do, now?

Question by Shagglepuff    |  last reply


how do you build a rpm meter and what is it called? Answered

Iv been tring to design a time mechine for a few months now and the best solution to this problem that i could find was gravitational time dialation this is the thery inwich gravity slows time down inside the gravitational field. to do this i decide to build a big centrofuge with a power full motor but to do this i will need a rpm meter to mesure the angular velocty of the centrofuge but the bad part about this is i dont know where to buy 1 so i ducided to build 1 but i need 1 that feed data into a laptop through a usb port 

Question by lj123456    |  last reply


Ideal Gear ratio?

Hello i am competing in a design challenge at school. were were each given a 9v 12000 Rpm Motor, the object of the challenge is to build a land vehicle that can go 10m as fast as possible. we will be holding a race on november 3rd to see who has designed the fastest vehicle. anyway my question for the community is using a 12000 rpm electric motor what would be the best gear ratio to use between the motor and the axle to optomise take off speed as well as having a high top speed. (if the gear ratio is to high then the car wont accelerate fast enough to low then the car wont have a fast enough top end) so basicly im looking for that perfect med ground. if anyone here has had much experience with gears and help would be great thanks (PS the vehicle cant be any biger then a vhs case but can be as tall as i want it)

Question by brl60    |  last reply


Help about Pogramable intergrate circuit? Answered

Hi everyone i need help on my rpm counter project..i had found a circuit that use lm2917 as frequency to voltage circuit (2 output.-ve and +ve)... now i need a pic that can compute the voltage to display onto the 8x2 lcd screen.. did someone know which type of pic that i should use? could some one show me explain on how to pogram that circuit? did someone have done this project that could share  a little knowledge to me? i have a little knowledge in electronic..but i can understand english..thanks..

Question by kill_them_now    |  last reply


Using a 3 wire fan with Arduino? Answered

So I got a couple of 12v PC fans. They have a black wire, a red, and and yellow. So if you just hook up the red and black wires to 12v, the fan works, but you no way of controlling the speed. So this yellow wire, I'm assuming it's much like the control wire on a   servo? If I hook up this yellow wire to the Arduino should I be able to control the speed of the fan using PWM??? I just want to be sure before I fry my Arduino :D Thanks!

Question by HavocRC    |  last reply


What motor should I get? PLEASE HELP?

For science fair,  i need to make a car for a 'king of the hill' type thing I need 2 motors (one for each back wheel) that can get me up the hill relatively quickly. The maximum power source i'm allowed is two nine volt batteries at one time (i can switch out dead ones in between runs) The hill is 40 inches in height and the ramp leading to the top of the hill is eight feet long The motors need to have a driveshaft sticking out about 1-2 inches I'm not allowed to use remote control but i've devised a way so that the car will stop, regardless of what the motor is. A link to a website where i can buy the motors or where i could get them would suffice (please below $15 per motor) Help would be GREATLY appreciated edit: my car will weigh about 1 -1.5 pounds edit: i dont know a whole lot about which motor to get so if someone could (not to sound helpless) pick one for my situation that'd be great

Question by ishmal1103    |  last reply




What's up with slow rpm motors? Answered

What's the deal with slow rpm motors? I need one for a project and can't seem to find any online. Why not? Am I looking in the wrong place?

Question by noahh    |  last reply


How to find the rotating shaft rpm?

I have used AC motor of 750 rpm... motor then transmit its power to gear box then to shaft... on shaft rope drum is connected to do the required work i-e lifting or lowering of load

Question by waseemhaider.syed    |  last reply


is there any way to measure rpms cheaply?

We are making wind turbines in one of my classes and my team is making a tesla turbine as ours. we want a way to measure how fast the disks are spinning. please help.☺

Question by DehLeprechaun    |  last reply


Measure RPM and MPH on motorcylce with Arduino

Hi all, I have an idea for an Arduino based instrument cluster for my cafe racer (1980 xs400). My question is what kind of rotary encoder I should use to measure the rotation from the cables coming from the engine block and front wheel that went to the original cluster (shown in pictures). I want something that won't break at higher RPMs and is more or less water proof. I have an idea of how to code this on the software level as well, but I'm not to experienced with C/C++ so any help there would also be appreciated. The end goal for this part of the cluster is to output the RPM and MPH to respective WS2812B 5050 LED strips, and possibly a small oLED later down the line. If something could be made more clear on this post let me know and I'll try to elaborate. Thanks again

Question by AedanGraves    |  last reply


Reducing speed / RPM of pedestal fan

I have a 400 mm pedestal fan rated for 230V 50Hz AC, 120W with minimum 2200 RPM which uses motor coils winding for speed regulation. Its speed and noise is very much even at lowest setting. I want to reduce its speed even further. I am thinking of three options - one - changing the OEM fitted 3.00 micro-farad 440V capacitor with 1.5 or 2.0 micro-farad 440V capacitor, second - using a capacitance based speed regulator (used with ceiling fans) and the third - using a resistance based speed regulator (least preferred option though). Please tell which option will work fine without doing any harm to motor coil? Any other options are highly welcome.

Question by sharmavk83  


Stepper motor high speed(rpm)?

I need a high speed (rpm) stepper motor but i don't exactly know where and what to look for. I have recently assembled this project for a laser harp : https://www.instructables.com/id/Frameless-Laser-Harp/?ALLSTEPS I have finished everything but the stepper motor parts. The stepper motor I had ( 28BYJ-48 – 5V) had a high torque but was far too slow to split the beams properly. My stepper motor shopping has left me more confused than when i started. Where can I find a quick stepper motor that can run on say 5-24 volts? It seems the stats rarely include speed or rpm. Thank you for any help in the matter.

Question by TheIronHobo    |  last reply


Which Low RPM Gear Motor?

I am working on a robot that will have a grabbing claw, of sorts, and I'm not sure what gear motors to use to actuate the claw.  It needs to have significant gripping power, so the gear motor must be low-RPM and high torque.  The two best options I have found so far are these: 1. 12VDC Gear Motor, 7 Rpm 2-7/16" x 1-5/16" Dia. 2.  Tamiya 70110 4-Speed Crank-Axle Gearbox Kit   If I used the Tamiya gearbox, I would also have to buy higher voltage motors, so the cost of the two is approximately equal.  Because of its layout, I think the Tamiya would be easier to use, but I'm worried about stripping the plastic gears.  Also, I have a smaller Tamiya gearbox, and the axle has some play in it and is extremely noisy. The 12V gear motor, on the other hand, appears to be more robust and probably has metal internal gears, but it would make my robot a bit larger. Does anyone have experience with Tamiya gearboxes?  How do they handle high loads?  If anyone has any input on these two choices, or other motors you think would be even better, I'd really appreciate the help.  Thanks!

Topic by ben_k    |  last reply


Variable, low-RPM DC motor setup?

Hey guys, I'm hoping to build a motorized slider system for my DSLR camera. I'm going to build the slide from scratch and probably attach a motor with a pulley system to move the slide, this should give me the option of having the camera climb the slide if it's on a slight angle. I'm not extremely electronically inclined but I understand I will need a low RPM motor and a PWM unit to adjust the speed. I'm thinking RPM between 0.5 & 10 would be ideal. Could I buy one of these (http://www.aliexpress.com/item/12v-100w-pwm-speed-controller-motor-governor-DC6-15v-STP50n05-wholesale/1663330358.html) add a 12v battery and a 12v DC motor and call it a day? If this is the case, should I be aiming for a 10 RPM motor that I can turn the speed down on? Is a 12v battery/motor likely to give me reasonable torque for dragging a DSLR camera up a moderate incline? Battery life shouldn't be an issue as the longer the use the less RPM I'll need. Any thoughts would be much appreciated.

Question by tig5    |  last reply


Please can any1 help me to find out the RPM of a 120mm Fan via USB Idea ? without connecting the fan to the motherboard

Hi folks, i have a few PWM 120mm PC Fan's, but one is so cheap & nasty that it only had the power specs on it and i have quite a few fans like this but wanted to find out the RPM of it but without actually hooking it up to my motherboard of my PC as im severely mobility impaired and my pc is in such an area that it would take an able-bodied person a few days of removing the barricade-mountain of 'stuff', lol, from all around it to get to the PC, so... ive got a bunch of usb cables just sitting around so is there a way i can use 3 USB cables to connect to 3 individual ports to supply the 12v needed by this 120mm fan (and somehow reducing the 15v in total from 3-added USB sockets' power added together to give 12v and my USB Hub is powered) and also a way of connecting the PWM wire of the fan to one of the USB ports so that a software like SpeedFan could detect it being connected so that i could find out the RPM of it (and write up an instructable about it too !!) the only info on the fan is: DC Brushless 12V 0.30A this would be a great project i wouldn't mind sinking my teeth into and i simply cant afford such fancy devices like a digital stroboscope that measures fan RPM so kinda living on a shoe-string here and i would really love to make some kind of USB-type simple device that could detect any fan's RPM that plugged into it via 4-pin Molex or the 3-pin connector: would i need extra circuitry for the software SpeedFan to use to enable it to detect a fan at the USB Port ? would it be possible to make a simple schematic for me if circuitry would be needed (i can read-schematics (just-about, lol, only started learning electronics!) & make my own PCB's) & how would i drop 15volts to 12volts so that the voltage doesn't fry my fan ?!? any & all advice is greatly appreciated and i thank you all in advance !!

Question by offtherails2010    |  last reply


how do you know how many rpms your engine has?

Such as a weedeater.

Question by TSC    |  last reply


i want to make low rpm less torque 1kw generator or alternator?

Can someone please tell me that how to make 1kw low rpm generator or alternator , please tell me the specs of  generator or alternator which is easy to build and takes low rpm for power generation actually i want to make a generator or alternator which needs less torque and rpm , so please tell me the specs for making low rpm less torque generator or alternator specs like how much magnets do i need shape , quantity , grade of a magnet , rpm of a magnet , torque  , gauge of a copper wire , turns of a copper wire , quantity of copper coils , distance between copper coil and magnets etc ( i want rpm of a 1kw generator or alternator  to be 80 -100 rpm )

Question by MuhammadK19    |  last reply



is the 250 rpm dc motor is good for electric bike??

Is the 8kg-cm and 250 rpm dc motor is good for electric bike??  hi i have a 12v dc geared motor 250 : rpm 8 km-cm : torque is this good for build ebike ??

Question by ShocoM    |  last reply



Use LED VU meter as Tachometer?

Hi, i want to share and ask something.   Somedays back i bought a digital tachometer with dial and needle. I wanted to test it, so i connected its power terminals (12V) and connected the Tach input wire to audio speakers output (+ve) terminal and played a loud song.  I saw Tach needle going up at certain frequencies. I want to ask that if tach can detect audio signals SAME AS a VU audio meter does. So, CAN A LED VU METER BE CONNECTED SAME IN PLACE OF TACHOMETER  to detect car RPM signals.? Plz help and guide.

Question by waqasjamil    |  last reply


I have the main motor from a vacuum cleaner what can I do with it? Answered

The motor is very powerful. It runs off of 120 V AC. The cable that plugs into the wall runs electricity straight to the motor. It weighs about 3-4 pounds and has brushes. It has alot of torque. So much so that it will flip in the air to ~1.5 feet when it is first started. I believe it spins at perhaps 2000-3000 rpm though I'm not sure. This motor was the motor that powers suction in the vacuum cleaner. I would love if someone could tell me if I could either use it as an alternator (for pedal power electricity generation) or what I could use it as a motor for?

Question by cdubnbird    |  last reply


Is there a way to slow down the speed of a moter while keeping the power the same, without resorting to a gear system?

I have a lawnmower moter, and need to slow it waaaaayy down to like 30rpm but maintain the power (or as much of it as possible). I really dont want to have to use belts, chains, gears or any of that hassle.

Question by coatesy900    |  last reply



Use brushless DC motor (or stepper motor) as RPM sensor?

Hi all, I'm making an Arduino based digital instrument cluster for my 1980 XS400 motorcycle. all the old tach and speedo instruments are mechanical so I need to convert the spinning cable's rotation to digital RPM. I've tried IR tachs but I can't seem to get them to be accurate enough (the lowest RPM I could get out of them was about 375, which isn't low enough) I'd love to use a more mechanical means of getting the RPM. could I use a 3 phase DC motor to count RPM? if I can, how?

Question by AedanGraves    |  last reply


Will a leak in my muffler cause rpms to increase slightly ?

This happens in neutral as well as when in gear.  Only talking 2-300 rpms in each case.  Will be replacing muffler tomorrow regardless.

Question by BOB J    |  last reply


How can I limit the RPM of an electric motor by using resistors or trimpots? (cheap/simple way)?

I've done it with a small trimpot that almost ignited by heating. What the problem? The current is to high? To lower the RPM must i lower the current or the voltage? And what exactly do the resistance lower? voltage or current?

Question by vinacarv    |  last reply


why machine maximum tortion happened at low rpm?

What caused it happened

Question by ririd    |  last reply



How can I increase/amplify my rpm for a motor? Example: I rotate my wheel 5times it will rotate my motor 100+ times?

Along a generator and trying to figure out what is it that people do that allows them to amplify there rpms so they can rotate there motors faster. Saw some people put series of belts and gears or they use some device that they attach on to the motor "stub" is what I'll call it can't remember right now what it is called but the part that sticks out of the motor that you would put a belt on to spin it. Or hand crank it. Any help guys? Thank you! Have a great day, hope to get a response soon.

Question by onepower    |  last reply


I am building a v-axis wind turbine. I need to know what kind of DCmotor to use for a low RPM DCgenerator. Help me?

The winds in my backyard aren't extremely strong, but I want my design to work and provide a good amount of power if possible.  What kind of DC motor do I need?  Is it easy to create a DC generator from scratch for this type of thing?  Would the ideal motor have a low RPM?  (Because I'm pretty sure my turbine will have a low RPM) Low torque?  Obviously I'm just starting to wrap my head around all of these ideas.  How do I know which motor to get based off the information I am given from the site? Right now I am looking around at www.allelectronics.com , if anyone knows of a better site that would also be appreciated as well. Bottom line: I'm looking for as much power as I might be able to get, but I have low winds, and not a whole lot of money.  I was thinking I might be able to setup the axle to a pulley system with some sort of rubber band going from the axle to the motor, would this work? I know it sounds liek I haven't done my homework, but truly I have, I'm just getting drowned in the options and choices and possibilities at the moment. Thanks so much for you help!  I truly do appreciate your time to help me! Best regards, Aaron

Question by Mr. Retro    |  last reply


ntc thermistor for auto rpm pc fans

I have 470 ohm thermistors and i want to auto control my pc fans ie when the temperature is low the fans are off or low speed,when temperature go high the fans rpm follow up.is there a scematic how to do a pcb?

Question by napoleonis    |  last reply


Changing LEDs colours as a car goes up in RPM?

I'm buiding a buggy and would like to build a visual effect when going up through the RPM and have some LEDs in the back change colour as i complete in the night events,    My question is there  away of building a system that  runs off the aultnator as the RPM rises it changes the colours in the light out put

Question by Bazzabushmechanic    |  last reply


which has high rpm and torque, the 3v dc brushed motor or the 12v brushed motor, they are running the same at 6v battery

Is it advisable to use a 12v motor to have high torque and rpm than a 3v motor?they both run at 6v,

Question by antitaengbasuraman    |  last reply


Speed sensor

I have a 60 tooth ferromagnetic ring gear with a speed sensor attached. Each passing of a tooth creates a pulse in the sensor sending a signal to the ecu for calculation of attained rpms. It calculates the interval between the teeth to obtain the rpms, thus determining when to kick in the rev limiter on my 06 polaris ranger XP 4x4. Is it possible or even practical to eliminate every other tooth to "fool" the sensor into a lower rpm reading, and creating higher rpm levels within the motor?

Topic by hiatt65    |  last reply