Solenoid 101: What is a Solenoid?

Mar 12, 2025Updated Jul 1, 2025

What is a solenoid?

A solenoid is a device comprised of a coil of wire, the housing and a moveable plunger (armature). When an electrical current is introduced, a magnetic field forms around the coil which draws the plunger in. More simply, a solenoid converts electrical energy into mechanical work.

  • The coil is made of many turns of tightly wound copper wire. When an electrical current flows through this wire, a strong magnetic field/flux is created.
  • The housing, usually made of iron or steel, surrounds the coil concentrating the magnetic field generated by the coil.
  • The plunger is attracted to the stop through the concentration of the magnetic field providing the mechanical force to do work.
You’ll see a brief explanation of solenoid operation as well as a demonstration of the different types of solenoids.

This article was originally published by TLX Technologies

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