What device does the schematic symbol depict?

The schematic symbol shown corresponds to a pneumatic motor, which is a device that converts compressed air into mechanical energy to perform work. These motors are characterized by their ability to operate without the need for electrical power, relying instead on compressed air supplied from a pneumatic system.

Pneumatic motors are widely used in applications where explosive atmospheres are a concern, or where electric motors might pose a safety hazard. The symbol typically consists of a circle with an 'M' inside it, which is a standard representation in schematic diagrams for this type of motor.

In contrast, the other devices listed have distinct symbols and functions:

• A hydraulic pump would generally use symbols that include elements such as connected cylinders or fluid symbols.

• An electric motor would often display a different representation that might showcase electrical connections or coils.

• A compressor has its unique schematic symbols that reflect its function to compress air or gas.

Recognizing the specific characteristics of each device through their schematic symbols is crucial in understanding how they integrate into larger automation systems.