Ramsey MSC1C DC Motor Speed Control Kit

by Ramsey

Product Details

• Item Weight: 2.6 ounces
• Shipping Weight: 1.5 pounds (View shipping rates and policies)
• ASIN: B0002NRKGM
• Average Customer Review: 1.0 out of 5 stars  See all reviews (1 customer review)
• Amazon Best Sellers Rank: #102,701 in Electronics (See Top 100 in Electronics)

Product Description

You see, controlling a DC motor s speed is not as easy as varying its supply voltage. The motor loses torque (power) as the voltage is lowered and finally stops rotating. The MSC1 uses a technique known as Pulse Width Modulation - PWM - to control speed. This is the same system used on electric cranes, buses and subway cars. With PWM, the motor receives full voltage whenever energized - however, the duration of the voltage changes; it's sort of like flipping an on/off switch very rapidly! The motor rotates smoothly and with full power - no matter what the speed. The MSC1 will control DC motors from 3 to 50 volts at up to 10 amps! Complete instructions detail how the PWM circuitry operates and some hook-up ideas. Assembly takes only an hour or two. Kit operates on 9 to 12 VDC and controls motor supply of 3 to 50 volts. Includes our custom case set measuring 5 W x 1 1/2 H x 5 1/4 D.

Customer Reviews

Most Helpful Customer Reviews

2 of 3 people found the following review helpful:

1.0 out of 5 stars Worthless, March 16, 2011

By 

Daniel M. Pomerantz "dmp" (St. Louis, MO) - See all my reviews
(REAL NAME)   

This review is from: Ramsey MSC1C DC Motor Speed Control Kit (Electronics)

I bought this kit at an electronics store under the promise that using PWM it would slow down a DC motor without losing torque. The documentation even said that if it detected a stall it would apply full voltage until the stall was removed, allowing the motor to continue operation. After I built it, I had it verified by the tech at the store, and then I excitedly it up to realize that it, in no way, shape, or form, delivered on its promise. Sure it allowed the speed of the motor to be decreased, but at a signifigant loss of torque too! I couldn't use this in my application because at the speeds I needed, there was not enough torque to turn the motor.

The documentaion is very condescending, claiming that the company knows the kit works as advertised, and if it doesn't, then it must have been assembled incorrectly, but they provided some free phone support. I contacted the manufacturer to discuss why it didn't work, and the "engineer" I spoke to said I was confused in what it was supposed to do, or that he didn't know how it worked. Either way, he was no help what-so-ever and offered no resolution.

I put the controller on the shelf and then had another use for it a few months later where torque wasn't a big deal, this time controlling a DC centrifugal blower. It didn't work on that either. I took it back to the shop to get an explaination, and was told that the blower porbably converted the DC current to AC internally, so it wouldn't work in this case. Again, useless. Not as advertised.