Questions tagged [rpm]
Revolutions Per Minute, a measure of rotational speed or rotational frequency.
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Brushless DC motor power over rpm
I am trying to get my head around how to theoretically describe the relationship between power and rpm of a brushless DC motor. I want to do this to check which motors from a list of available ones ...
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Need a suggestion how to convert an analog signal to a digital signal
I am trying to make a speed monitoring system. I want to monitor motor RPM with an IR phototransistor sensor.
I am getting analog values and negative peaks when a sensor flashes on a reflective ...
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Calculating the torque and RPM requirements for a DC motor
Say I'd like to calculate the motor specs required for lifting a 1kg weight at a rate of 1 m/s. How much torque and RPM should the motor have, assuming a wheel radius of 1cm?
My calculations are as ...
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Exceeding max RPM of wind turbine [closed]
I have a wind turbine that reaches its max output power at 1000 RPM, and I want to know if there's any problem if I make it go faster than that (e.g. around 1250 RPM).
I have a TESUP Yuzo. You can ...
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Advice needed for super low noise motor 15-30 rpm motor for diy project
I am doing a project where i have to rotate a hardboard disc of 20 inch diameter using a motor.
The disc is about a 1lb heavy. My current set up is using a 12V 20rpm DC motor from Amazon store:
https:/...
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How do I calculate the RPM and torque of a 12 V DC motor that gets 5 V?
I have a PCB that outputs 5 V to each of the two motors. It was part of a robotics kit that included two 12 V 360 RPM motors.
I want to attach a 12 V DC motor with 3500 RPM. How do I calculate how ...
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RPM of a motor from frequency
I have a very old motor which I can't find any information about. I need to calculate its RPM for some work. I've attached a cog to it, held a piece of paper up to it and recorded the pitch. It was ...
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Will running four motors (two high speed and two high torque) get the robot rolling? [closed]
I've been building a 2WD robot for 3 months now and been switching the motors frequently and been running into the same issue - low torque.
I had these low RPM, high torque motors around and thought: ...
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How can I calculate RPM for a DIY custom BLDC motor that works on 12/24 volts?
I'm working on a project where I'm designing a 12/24V BLDC motor. I have nine slots for winding and eight neodymium magnets. I used this for calculating the winding factor which is 0.94521 and winding ...
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How can I connect two motors in parallel with different RPM and voltage?
I have a kid's electric toy car with a 12 V battery and 2 DC motors (Model: RS380/6 V & 12 V with 15000 RPM) connected to battery in parallel and to wheels using gearboxes. For some reason, the 6 ...
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Two-pole motor driver circuit
I am working on the following circuit. This circuit is the driver of a two-pole DC motor using a MOSFET as a switch.
The coil voltage is 48 V.
MOSFET M1,M2 = STB4NK602T4
Coil1 & coil2 (two-pole ...
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How is power consumed by an induction motor calculated based on speed (from a VFD) and torque induced by the rotor shaft?
I've been tasked with carrying out some design improvements on my company's production floor.
There is a flat belt conveyor assembly line, whose movement forward movement is controlled by a single ...
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Is it OK to reduce fan speed by reducing voltage?
I have this air cooler whose speed is just too much even on the lowest speed setting, so I added one more speed controller(or regulator) in series which is basically used to control the ceiling fan ...
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How to reduce the RPM of a DC motor
I need a small 3-pole commutator motor with 4000 RPM @ 12 V and the best I can buy is 8000 RPM @ 12 V. I am considering buying an 8000 RPM motor and replacing the existing windings with thinner wire.
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Brushed DC Motor Closed Loop Speed Control Under Load
I've designed a PI controller to control brushed DC motor speed between 0.6Hz - 6Hz (RPM:36 - 360). When I control the motor speed at 0.6Hz (approximately 4.0V supply and 60% PWM duty), it can rotate ...
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Is it normal that a 12 V DC motor changes its RPM depending on its orientation?
I got a 40mm brushless DC fan from SHENGSHIDA which is rated at 12V and 0.15A. I supply it with 5V from a Raspberry Pi.
I noticed that the rotational speed of the rotor changes depending on the ...
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MAX9926 Maximum Variable Reluctance Input Frequency
I am planning on using the MAX9926 to read 2 variable reluctance (magnetic pickup) sensors installed in the crankcase of an engine. The sensors will read the teeth of the starting gear to get the RPM ...
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What is the effect on speed and power when we connect three motors on a single shaft? [closed]
Rolls Royce used three 750R (YASA) motors in their aircraft "Ionbird." All motors are mounted on the same propeller shaft.
What is the effect on the overall speed and power of the motors?
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How can this BLDC motor have constant torque over its RPM range?
I was going through this catalogue of BLDC motors for my EV project. I found two motors in it, one rated at 2.5 kW of peak power, and the other 6 kW of peak power.
My questions are as follows:
It is ...
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How to convert pulse width modulation (PWM) of DC motor to RPM or distance traveled?
I have a DC motor attached to a robot car wheel which can give me the PWM data as the motor is linked with the TB6612FNG H-bridge, but there is no other sensor to measure the RPM of the wheel. The ...
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Fan humming sound when decreasing speed with a dimmer [closed]
I am using a ~large 400mm wall mounted metalic fan (specs below).
I wanted to decrease the speed (and noise) with light dimmers (I tried 2 models so far) but when speed is decreased it makes humming ...
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how can rpm of a brushed dc motor be measured
My brushed dc motor spec. sheet lists BACK EMF CONSTANT (Ke) V/K R.P.M. 20.8. So knowing/controlling the voltage sent to the motor would make it easy to calculate, and set the rpm. My problem is my ...
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Underwater train project's battery powered DC/BLDC/Stepping motor gear/non gear requirements and water proof sealing problem
I am a software developer by trade, having put together a few beginner Arduino projects and such.
My next project entails an underwater roller-coaster (without loops, just going over the surface, so ...
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Determination detection of direction with 2 optic sensors which are on opposite sides of disc
I would like to ask you is it possible to detect the direction of rotation with 2 optic sensors which are on opposite sides of disc? In the disc is small hole, when the part with hole goes through the ...
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Average data transfer rate
I am learning computer architecture and organization I am stuck in the following question.
Consider a hard disk with sector size 1024 bytes, 5000 tracks per surface,
64 sectors per track, and 8 ...
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DC Motor, Torque vs RPM
I am making a pulley system (for an electric bike) that requires about 300rpm and 40lb-inch torque. The motor that I am looking at is a 24V DC Permanent Magnet Electric Motor Generator 250W 2750RPM ...
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Need to increase the amplitude of op-amp output
I'm using this circuit to measure the RPM of a DISC rotating at 24000 rpm. This circuit is working fine. But the problem is with amplitude. It should be of 4.2V, but actually is of 2V as shown in ...
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What is the relationship between the RPM, power, and impedance of an induction motor?
Does an induction motor draw more power at higher RPM?
Increasing the frequency of the AC power supply will increase the RPM of the induction motor. However, that should also increase its impedance (...
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How to lower the RPM of a motor without using PWM or gears?
I need to lower the RPM of a simple DC motor to almost 20 - 30 RPM for some reasons. I cannot use PWM signals or gears to lower the RPM of the motor (I know how to use them but I want a simple ...
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Does this motor have a gearbox inside?
I have a DC motor and the sticker says its rated for 24Vdc and 3700rpm.
There is an AC tacho inside it which I am using to measure the speed of the motor.
So when I run the motor with a 24Vdc supply ...
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Converting pulses to RPM
I have a question about how to take an output from a sensor and calculate RPM.
The sensor produces a square wave at a maximum frequency of 1kHz.
So I think I have two options:
Count rising edges in a ...
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Why don't *small* electric cars use small cheap hobby motors? [closed]
The automotive blogger Jason Torchinsky recently bought an inexpensive electric car, a Changli Nemeca, whose motor he describes as being powered by five car batteries and producing 1.1 horsepower (820 ...
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How much load DC motor can move? [closed]
with 1000 rpm how much load it can move on 12v?
I want to no load of DC gear motor on 12v and 5v
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Difference between analog and digital rpm controller
I was doing some research into RPM governors for diesel engines and could essentially find two different approaches. One was based on some NE555 based PWM circuit that based on the input RPM from a ...
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BLDC Motor question
Im looking for a solution, i have a 3kW 320V 3000rpm rated BLDC motor with position hall encoder and a chinese driver. The hall-feedback is working with it.
I would like to use motor between 15 and ...
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Alternator output rating
Overview:
I am currently working on a project that requires a 24v alternator, which is powered by a mower engine.
This engine in particular runs around 3,000 RPM, and does not exceed 3,200 RPM (based ...
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Torque issues with DC motor
I am currently trying to use a DC motor with a lead screw to eventually open an close a window. My window requires around 2 kg's of force to open and the distance that needs to be traveled is 20 ...
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Calculations for a DC motor
I want to open and close a window using a DC motor and a lead screw. My window is 20 inches long.
I know buying recommendations are outside the scope of this forum. I have little to no knowledge ...
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How does gearing affect power generated by a permanent magnet DC motor?
I am currently working on a project to harvest electrical energy from a rowing machine. I am trying to make use of gearing ratios to adjust the resistance level offered by the system, and the impact ...
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Alternator and voltage regulator recommendation(s) for antique engine based 12V power source
What would be good hardware to provide 12V DC for battery bank charging driven by an antique stationary engine that does not run at a steady RPM?
These old engines can run on practically any liquid ...
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How to calculate RPM from a square wave signal Voltage-Time graph
I'm struggling to understand how to show the relationship between the input and output of a hall effect sensor used as a wheel speed sensor through mathematical expression. How can I calculate the RPM ...
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Correct way of calculating BLDC torque for a given RPM and Current
A permanent-magnet 3-phase brushless DC electric motor is attached to a load.
Motor is operated with vESC6.6 inverter, which is software-limited to 140A. Measured efficiency at maximum power is 81%.
...
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Is 1 Hz equal to 1 rotation of a motor shaft?
I'm rather new to the world of electronics but I have been trying to find the frequency of a DC motor. I've found that 1 hz is equal to 1 revolution per second, but does that refer to shaft rotation ...
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Confusion with RPM calculation of a DC fan from its datasheet
I want to calculate pulse periods from a tacho output of a DC fan. I want to read pulses by a MCU and convert them to RPM and display in LCD.
But I'm confused with the following description of RPM ...
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If a high rpm motor is run at lower rpm, will it produce more torque?
I did the following calculations:
Max current = 1.2A, Max voltage = 12V
Then power = 14.4 watts = 0.019hp
Rpm = HP * 5252 ÷ torque
I need a torque to 2kgf-cm = 0.144 lb-ft
Gives rpm= 698.
Thus this ...
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ratiometric hall effect sensors outputs at high RPM
Im using an allegro A1308 linear ratiometric hall sensor to measure the rpm and angular position in a shaft rotating at 20K rpm. My magnet is a 2mm dia 1120 mT magnet placed at around 15mm from the ...
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How to properly utilize RPI 1391
I'm trying to get going with the RPI-1391 sensor but I'm obviously doing something wrong.
I'm connecting it to a Raspberry Pi, where:
Pins 1 and 3 are connected to Pi's ground
Pin 2 is connected ...
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Is there an economical 2-3 RPM 120v motor with speed control? Or what components could I use to achieve that scenario? [closed]
I've got a mechanical design for a piece of catering equipment and I need to figure out a way to achieve some variable speed control for a slow RPM motor. This is a direct drive application (imagine ...
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Motor Speed Output Signal [closed]
I need an advice.
I just got a DC motor and its controller board.
On the controller board it has 6 pin/wire: +12V, GND, PWM, ENABLE, DIRECTION, SPEED OUT.
What I want to know is how do I interpret ...
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Calculating RPM from Angular Changes
For a project, I have to determine the RPM of a turning resolver. I can correctly read the angular position of the resolver as as a hex number via an RDC. This number is then converted into a 14-bit ...
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