I built a Pulse Width Modulator to control the speed of a 12V DC motor, but the motor doesnt even turn until the potentiometer is at 50%. How can i fix this? Let me give more background. I took apart a Skil 12VDC 1 Amp Drill and removed the motor, gearbox, transmission, and chu…

Right. Operating under those Right. Operating under those assumptions, lets assume the at 0 resistance with the pot the motor is at 99% cycle, and at maximum speed. wouldnt the case hold true for being at 90% resistance of the pot, thus we have 9% cycle, the motor should still tu…

beeping beeper Sounds like you are doing it right. from the manual, page 12: Connecting the Test Leads The meter sounds a warning tone when you set it to measure anything except current and you connect a test lead to +10A MAX. This reminds you not to touch the circuit with the t…

So it seems like I could So it seems like I could measure the amperage at the load, while the motor is on, then remove the motor, and measure the voltage with a load under the 400mA fuse(( ( a 12v LED or some such) for measuring DC Voltage…So I’ll have numbers in a few hours

Dual failure? The PWM drive mentioned doesn’t appear to tell what PWM frequncy is being used, so only an oscilloscope (or a special multimeter) might be able to discern that.Might or might not be important. The motors it typically drives appear to be model train motor, which are…

I took some readings and… It seems that either the PWM is not functioning as predicted, or my multimeter averages values. I first hooked up the motor and decreased pot resistance until the motor started to turn. It read roughly around 1 amp, then raise the resistance and the amp…

12VDC >10AMP PWM I found a schematic for a 12VDC-24VDC >10 Amp PWM, do your 12V DeWalts pull more than 24 Amps? Here is the link for the schematic… http://solorb.com/elect/pwm/pwm1/ perhaps this is the PWM that I should be using Append: After more research some of the 12VDC dr…

Current in a box Many Battlebots guys use NiCad packs that can dump current at a higher rate many wall power supplies. Lead Acid does very well too. A controller that can handle that much current is really needed as well. Innovation First, Robot Power, Vantec, Robot Solutions al…

Nicads were awesome back in Nicads were awesome back in the day and still are. the newer type cells nimh and li-ion have better charging and less memory issues but cost more. You can pull quite a few amps from the nicads…I know some of the folks were pulling something wickid 30+…

measuring averages The behavior of your meter is to be expected. At minimum duty cycle (you describe that as max pot resistance), the pwm controller puts out very short bursts of 12V. Your meter is not an oscilloscope, so it can only present you one reading: an average voltage o…

Options So it seems to me as I have few options: I would like opinions since I’m fairly new at this. Keep in mind what i’m after is speed control at max torque without that initial jump in speed due to the stall current. My bot is about 5 lbs or so and only has the one drive mot…

PWM not causing motor to turn until 50%

Community General Discussions

BaseOverApex September 26, 2008, 2:15pm 22

Doo-Hickeys

These Doo-Hickeys are designed to be plugged into the receiver of an RC car in place of a regular servo, so if you buy one that advertises itself as for this purpose, then you can send it a srandard servo pulse from your picaxe (or other servo controller).

Measure output voltage PWM motor driver, RMS and average voltage, dc motor parameters