What Is a Remote Solenoid?

A remote solenoid is a device that produces a working motion, allowing operators and automated systems to activate secondary devices from a remote location. This functionality is made possible by the translation of electromagnetic force to linear motion by the solenoid. A typical solenoid consists of a static, wire wound coil connected to a electric power source and a moving, spring loaded ferrous metal plunger positioned close to the coil. The plunger is, in turn, attached to the secondary device via a set of linkages. When the coil is energized, a strong magnetic field is generated around it, attracting the metal plunger, which moves toward the coil, transferring the required motion to the secondary device in the process.

The simple physical act of switching on a light, opening a door or putting a compact disc (CD) in a CD drive are generally carried out by most people without any conscious thought. In some situations, though, the device that requires the action is too far away, in too tight a space or somewhere dangerous. This type of situation probably accounts for more work requirements than manual inputs do, and it is the domain of actuators such as the remote solenoid. These devices supply working movements used to switch devices on and off, move things and operate machinery remotely or as part of an automated or pre-programmed system.

Solenoids are one of the most common types of actuators, and they produce a bi-directional linear movement. The remote solenoid is very simple, consisting of a wire wound coil and a spring-loaded, moving ferrous metal plunger. The remote solenoid coil is connected to a suitably rated alternating current (AC) or direct current (DC) power supply. This circuit generally is interrupted at some point by a control system such as a push button or automated interface. A series of linkages are used to attach the plunger to the device that requires activation.

When the remote solenoid control circuit is switched on, power flows to the coil energizing it. This creates a powerful electromagnetic field around the coil. The magnetic force attracts the metal plunger, causing it to move very rapidly toward the coil against the tension of the spring. The plunger is connected to the secondary device, so this motion is transferred to it, effectively switching it on or moving it into place in the process. When power is cut to the solenoid, the spring tension on the plunger returns it to the neutral position, completing the remote solenoid's characteristic bi-directional movement.