The PH1240-N8 St. Louis Motor is a classroom demonstration apparatus which shows the relationship between electric and magnetic fields and the electric motor as a common application of electromagnetism.
The St. Louis motor was first made for use as a classroom instruction tool because all parts of the motor can be seen and studied. Students can explore how a simple electric motor works by doing a series of investigations. This demonstration will also check students' understanding of electromanetic concepts and reinforce on how to apply the right hand or left hand rule. This particular St. Louis motor can be adjusted so students can study the effect of voltage and position of the brushes on the commutator. The motor consists of a two pole D.C. armature. The brush holder, with two heavy binding post terminals, can be rotated for experiments. The permanent bar magnets are supported by spring brass clamps which allow the magnets to slide in and out easily but stay securely put once adjusted to the desired location. Not included but necessary for this apparatus are 4 D cell batteries with holder or a power supply and two connecting leads with either alligator clips or plug ends (preferably one red and one black). You may also wish to use a compass and two crescent or box end wrenches for tightening and loosening nuts.