12v dc small motor, speed control,

AI Thread Summary
The discussion revolves around controlling the speed of seven 12v DC motors used in a model of an American police car's roof bar light. The user needs five motors to run at approximately 100 RPM and two at about 50 RPM, without requiring precise synchronization. Suggestions include using a simple voltage or current regulator to achieve the desired speeds. The project is a one-time effort for a traffic cop's show vehicle, and gearmotors are recommended as a potential solution. The user is seeking advice on parts and suppliers to facilitate this project.
polmech
Messages
2
Reaction score
0
Hi anyone
I have 7 small 12v dc motors RF-500 TB, max efficiency 0.08 amp max speed 2180 rpm.
These motors are just holding plastic reflectors of an american police car's roof barlight, they are individually fitted in separate pods with their own 50 watt bulbs.
I need 5 pods to spin slower than the other 2, but all to spin a lot slower than when the cars 12v supply is added from the battery ( 2180 rpm the reflctor would take off!).
I have asked several parts distributors, They can supply the part but can't tell me what part i need ( Head against brick wall).Any help with what i need and where to get it would be really really appreciated.
Thanks in advance
Mat
 
Engineering news on Phys.org
Shouldn't be a terribly difficult project. Since the load on the motors is constant, a simple voltage or current regulator can probably do the trick.

Some additional info will help:
Do the motors need to run synchronously (as a set of 5, and/or the "faster" pair), or can the speed vary a small amount between each motor?

Define "a lot slower" -- 10 rpm, 100 rpm, 1000 rpm?

Is this a one-time project, a couple of dozen units, or continuing production?

Are these the motors? http://www.jameco.com/webapp/wcs/stores/servlet/Product_10001_10001_238511_-1
 
i think you'll want gear-motors.
 
Hi pantaz, Thanks for your reply.
I would need the 5 to run about 100 rpm and the other 2 about 50 rpm if poss, and no they don't have to be spot on synchronised really.
This is a one time project for now and a learning curve for me. It is a traffic cop friend of mines american police car that he run's for fun for shows etc.
The motor in your link looks like the one.
Thanks for your interest.
Mat
 
I'd try servocity.com and look for gearmotors.
 
Hi all I have some confusion about piezoelectrical sensors combination. If i have three acoustic piezoelectrical sensors (with same receive sensitivity in dB ref V/1uPa) placed at specific distance, these sensors receive acoustic signal from a sound source placed at far field distance (Plane Wave) and from broadside. I receive output of these sensors through individual preamplifiers, add them through hardware like summer circuit adder or in software after digitization and in this way got an...
I am not an electrical engineering student, but a lowly apprentice electrician. I learn both on the job and also take classes for my apprenticeship. I recently wired my first transformer and I understand that the neutral and ground are bonded together in the transformer or in the service. What I don't understand is, if the neutral is a current carrying conductor, which is then bonded to the ground conductor, why does current only flow back to its source and not on the ground path...
I have recently moved into a new (rather ancient) house and had a few trips of my Residual Current breaker. I dug out my old Socket tester which tell me the three pins are correct. But then the Red warning light tells me my socket(s) fail the loop test. I never had this before but my last house had an overhead supply with no Earth from the company. The tester said "get this checked" and the man said the (high but not ridiculous) earth resistance was acceptable. I stuck a new copper earth...
Back
Top