Which statement about DCV schematics is true?

DCV schematics, or Directional Control Valve schematics, are designed to illustrate the various positions and functions of the valve within a pneumatic system. The correct statement asserts that DCV schematics show all positions of the DCV. This includes not just the default or resting position but also any alternate positions that the valve can assume during operation. By depicting all possible positions, these schematics provide crucial information for understanding how the valve directs airflow or fluid through the system.

This comprehensive representation allows technicians and engineers to analyze and troubleshoot the system effectively, as they can see how the valve interacts with other components in different states. Understanding all positions is vital for designing control systems, diagnosing faults, and ensuring efficient operation of pneumatic circuits.

The other choices do not accurately capture the full functionality shown in DCV schematics, which is why they do not hold true. For instance, stating that DCV schematics only show the default position, or that they never show operation methods, misrepresents the purpose and detail provided in these important documentation tools. Additionally, omitting blocked paths would undermine the purpose of creating a full picture of the valve's operation within the system.