Question I am constructing a prop for our high school musical which calls for a plane with a spinning propeller. We received a 12 volt DC electric trolling motor to use to turn the prop. I would like to slow down the rpm's electronicly so as not to injure any of the students on stage. The manufacturer states the amperage used is from 25 down to 5 amps.
Answer Usually small motors are permanent magnet design. Thus the 12 volts are fed to the armature circuit. To adjust speed you need to vary the voltage 0 to 12 Volts. The current will vary accordingly based on the load.
For variable voltage supply you need to buy a DC drive or variable power source such as a variac and then rectified.
Electric motor winding redesign, AC and DC. Troubleshooting, motors controls generators. Vibration analysis, dynamic balancing, root cause analysis: electrical and mechanical.
thirty five years electro-mechanical and Senior Management
Organizations EASA, CSA, ASTTBC, FSR
Education/Credentials Journeyman Motor Rewinder, Millwright, Industrial Electrician, Vibration Analyst level II. Certified Electrical Technician ASTTBC, FSR Class B, in BC. Laser alignment specialist. Marine machinery repairs. Business Management Certificate. Last 19 yrs as Plant Manager