What range should my POT be?

Started by kayvee in sci.electronics.basics11 years ago 23 replies

Okay, so I have this motor and it is powered by a 24VDC power supply, and I would like to vary the voltage going to this motor. This motor draws...

Okay, so I have this motor and it is powered by a 24VDC power supply, and I would like to vary the voltage going to this motor. This motor draws 0.4A with 24V. I understand that connecting a pot normally to this motor will burn out the pot rather quickly, so one must use a NPN transistor. I reckon in this fashion: V+ ---+---------------+ | | P /c ...


Help Trying to Use D.C. Motor as Generator

Started by Techmann in sci.electronics.basics11 years ago 16 replies

I have a D.C. motor that spins just fine when I apply 12V to it. The motor has a 1/4" shaft and I would like to use it as a generator. When I...

I have a D.C. motor that spins just fine when I apply 12V to it. The motor has a 1/4" shaft and I would like to use it as a generator. When I hook up a DC voltmeter to the leads and spin the shaft in the same direction with my electric drill (around 1000 RPM) the most I see out of the motor is only .24 volts. I am puzzled why I am not seeing close to 12V output on this motor. Can only cer...


motor wiring / Keeps starting and stopping

Started by Steve Wolf in sci.electronics.basics2 months ago 4 replies

I have motor that was removed from my furnace when a new furnace was installed. I know the motor is good as I replaced it few years. (2 Y...

I have motor that was removed from my furnace when a new furnace was installed. I know the motor is good as I replaced it few years. (2 Y Old). At the time, instead of replacing the motor with a "Furnace" motor for 400 dollars I replaced it with this one for 90 dollars. It worked great until I replaced the furnace. I thought I would now turn it into a grinding wheel. I connect up two wires...


BLDC motor questions

Started by Anonymous in sci.electronics.basics3 years ago 19 replies

Awright youse motor folks, I need info. I have, over the last couple years goofed around with BLDC motors made for RC hobbies. I even made a...

Awright youse motor folks, I need info. I have, over the last couple years goofed around with BLDC motors made for RC hobbies. I even made a couple just to learn winding techniques. The motors are rated in part by the kv of the motor, which is how fast it will spin when powered at a given voltage. The kv stands for thousand revolutions per volt. A hand wound motor, or any motor for that matte...


Stepper motor controller help please

Started by Anonymous in sci.electronics.basics7 years ago 7 replies

I recently acquired a programmable stepper motor controller. It was made by Richmill Manufacturing Company Ltd. around 1982. It is designed to...

I recently acquired a programmable stepper motor controller. It was made by Richmill Manufacturing Company Ltd. around 1982. It is designed to drive a unipolar stepper motor. The guy I got it from said it worked fine when he put it away and then upon trying it about a year later it only works intermittently. I did discover one wire in the cable that goes to the motor does not have continui...


Multimeter Question

Started by Rob Snyder in sci.electronics.basics8 years ago 12 replies

So, I think I learned the hard way this morning that you're not supposed to measure the voltage of an AC motor across the motor's terminals...

So, I think I learned the hard way this morning that you're not supposed to measure the voltage of an AC motor across the motor's terminals while it is running (sparks flew, fuse blew). Am I correct in that I shouldn't have done this, or is it safe to test the motor this way - implying that something else happened? I don't often deal with AC circuits so it's all a bit of a mystery to me. I...


Thought experiment-will this work?

Started by Anonymous in sci.electronics.basics7 years ago 4 replies

I think I pretty much understand how induction motors work. A typical single phase motor has a start winding that is approximately in quadrature...

I think I pretty much understand how induction motors work. A typical single phase motor has a start winding that is approximately in quadrature electrically to the run winding. This provides the phase shift that gets the motor spinning. Energizing just the run winding with the motor just makes the armature rotate back and forth a tiny amount. In a three phase motor the windings are 120 degre...


need help with dc motor controller using spst momenrary button.

Started by Sweetie Pinellas in sci.electronics.basics4 years ago 10 replies

I am looking for a way to control two SPDT relays configured in a ground common configuration like in the link below, which will control the motor...

I am looking for a way to control two SPDT relays configured in a ground common configuration like in the link below, which will control the motor in three states. Normally it would use a SPTT toggle, but I want to have it operate on momentary spst push button. Push and hold it and motor turns clockwise, release and it stops, press again an hold it and motor turns counter-clockwise,


BLDC motor questions

Started by Anonymous in sci.electronics.basics5 years ago 12 replies

DC motor questionsAll, I am making, or at least attempting to make, an electric high speed spindle that fits in a confined space. I do not...

DC motor questionsAll, I am making, or at least attempting to make, an electric high speed spindle that fits in a confined space. I do not want to use air as the motive force. So I have been experimenting with BLDC motors made for model airplanes and the like. I would like to cool the stator, I think I may need to in fact if I want the motor to run continuously. Liquid cooling would be bes...


How to sense motor current to actuate brake?

Started by Anonymous in sci.electronics.basics11 years ago 16 replies

Greetings All, I'm using a servo motor to drive a slide and I would like to sense the current it draws in order to actuate an electromagnetic...

Greetings All, I'm using a servo motor to drive a slide and I would like to sense the current it draws in order to actuate an electromagnetic brake. So the more current the motor is drawing the more drag the brake puts on another shaft. The motor is a DC permanent magnet type and will be drawing 20 amps max at 80 volts max. I'm trying to accomplish a force feedback system. The amount of drag...


24V-> 12V reduction for dc motor

Started by Greg Russell in sci.electronics.basics8 years ago 10 replies

Hello all, I have a 12VDC motor that I wish to intermittently run in a 24VDC system, and am wondering how I might efficiently reduce the...

Hello all, I have a 12VDC motor that I wish to intermittently run in a 24VDC system, and am wondering how I might efficiently reduce the voltage, please. The motor draws 40A at initial torque in a 12V system, but quickly drops to ~1A. If my beginner's knowledge serves, that would mean 20A initially in the 24V system. If E=IR (voltage=amperage*resistance) then does an inline resistor...


DC potentiometer

Started by Joe Schmucker in sci.electronics.basics8 years ago 34 replies

Easy question from a really dumb noob. I have a 9volt DC motor that draws 500 ma current. Is there a simple potentiometer I can put on this...

Easy question from a really dumb noob. I have a 9volt DC motor that draws 500 ma current. Is there a simple potentiometer I can put on this motor to control the speed? It is on a wire fed welder that is either ON or OFF. I want to control the speed of the feed motor. Appreciate any advice. If you slam me for being a dorkus, I will take it. I'm not too thin skinned. :-) Joe


Accelerometer

Started by Anonymous in sci.electronics.basics4 years ago 3 replies

Hi, I am controlling a single axis DC motor to follow the elevation of the Sun using two light sensors. The motor moves 180 degrees in a day....

Hi, I am controlling a single axis DC motor to follow the elevation of the Sun using two light sensors. The motor moves 180 degrees in a day. The control circuitry of the motor ( solar tracker) will be mounted on the moving solar panel mechanical assembly. I want to know the changing tilt / position. I choose the following accelerometer to calculate the tilt from dimension engineerin...


0.5 rpm motor

Started by dave...@yahoo.co.uk in sci.electronics.basics4 years ago 10 replies

hi, i am in the uk, and need a 0.5 rpm ,low voltage (3v to 12v)motor no real torque needed its just to rotatae a disc slowly.....anyone know...

hi, i am in the uk, and need a 0.5 rpm ,low voltage (3v to 12v)motor no real torque needed its just to rotatae a disc slowly.....anyone know what might do ? dave


req: help to wire a 1phase ac motor

Started by Garth Oor-Tael in sci.electronics.basics11 years ago 3 replies

Hi, I would appreciate help in wiring a 1 phase AC motor. I tried getting a diagram but couldn't find any for this motor. Here's what I...

Hi, I would appreciate help in wiring a 1 phase AC motor. I tried getting a diagram but couldn't find any for this motor. Here's what I know: -3 leads coming out (red, blue, black) -2 visibly different wiring inside (colors: red-ish, gold-ish) -need an external capacitor (which I have) Inductance measurements: black-red: 12.18 mH black-blue: 13.14 mH red-blue: 30.0 mH Info...


AC fractional synchronous motor

Started by Richard in sci.electronics.basics9 years ago 14 replies

I have a well-made vintage motor (used in a vintage professional chart recorder)and the motor is marked "Synchronous". (Evershed & Vignoles...

I have a well-made vintage motor (used in a vintage professional chart recorder)and the motor is marked "Synchronous". (Evershed & Vignoles type FCX31/AS15 and it's about 2 long and 2" diameter). Four coloured wires come out of it and seem to be marked as follows: Blue: "1" Yellow: "2" Red: "X" Green: "Y" "1" - Connects to "X" and a wire that goes to capacitor. "2" - Connects to...


Help please with DC motor control

Started by Anonymous in sci.electronics.basics5 years ago 23 replies

Greetings All, I am working on a project in my shop that requires constant tension on a nylon cord. The cord comes is pulled off of a spool a...

Greetings All, I am working on a project in my shop that requires constant tension on a nylon cord. The cord comes is pulled off of a spool a certain amount and cut. I have drag on the spool because I don't want it keep spinning when I'm not pulling. But pulling against this drag is tiresome. So I was thinking that I could use a motor to help pull the cord. The motor would not have quite eno...


Controlling a Stepper Motor.

Started by calcasmy in sci.electronics.basics8 years ago 4 replies

Greetings, To start with, I am not even a beginner and am planning to learn... I am trying to control a stepper motor. This is where I got so...

Greetings, To start with, I am not even a beginner and am planning to learn... I am trying to control a stepper motor. This is where I got so far: 1. Stepper Motor connected to power supply (12V) with darlington pair. 2. Converted USB serial signals to parallel signals for connecting to the darlington pair. 3. I wanted to use a microcontroller, but didn't want to complicate it (next ...


*analog* brushless DC motor control?

Started by Anonymous in sci.electronics.basics7 years ago 19 replies

My son and I took apart a dead hard drive, and salvaged the motor. Apparently it's a brushless DC motor that needs a dedicated controller. Any...

My son and I took apart a dead hard drive, and salvaged the motor. Apparently it's a brushless DC motor that needs a dedicated controller. Any way it can be powered by analog, discrete circuitry? If I understand it correctly, each of the three power wires needs to be energized while the other two wires are held at ground, and the three wires take turns being powered by, what, +5V, right? ...


Issues with a stepper motor drive

Started by chetanthegreat in sci.electronics.basics4 years ago 6 replies

Hello folks, I am facing some issues regarding a stepper motor drive. The stepper motor I have is a 20KG 12V DC L/R Full step driven one. I...

Hello folks, I am facing some issues regarding a stepper motor drive. The stepper motor I have is a 20KG 12V DC L/R Full step driven one. I need it to drive a Lead screw which eventually builds up pressures of the likes of 400Kg cm in a cylinder. I have attached a gear box of ratio 12:1 to the stepper and tried boosting the torque. With the direct coupling the pressure used to reach aroun...