DC Motor Speed, Current and Stall Lab
A 12 V battery runs a DC motor through a switch and a 15 A fuse: about 3000 rpm and 1 A with no load. Lower the voltage, add load, reverse the battery or…
Use this circuit in class: DC motor experiment: speed, current and back-EMF
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A DC motor is a winding and a magnet: the current turns the rotor, and the turning rotor makes a back-EMF that pushes against the battery. That is why a free-running motor draws only about 1 A here, while a stalled one draws V ÷ R, up to 20 A at 12 V.
Change the battery voltage, the motor’s Load (%) and Locked rotor settings, or flip the battery, and read the speed, the current and the back-EMF on the motor’s labels. The 15 A fuse protects the motor if it stalls at full voltage.
What's inside
- 1× Battery
- 1× Switch
- 1× Fuse
- 1× DC Motor
- Measured with Voltmeter/Ammeter
