Which device in pneumatic systems is used to decrease pressure to desired levels?

In pneumatic systems, the device that is specifically designed to decrease pressure to desired levels is the regulator. Regulators control the output pressure of a gas by allowing the user to set and maintain a specific pressure level, regardless of variations in input pressure or flow rates. This is crucial because it ensures that the pneumatic equipment operates effectively and safely within the required pressure range, which is essential for optimal performance and to prevent damage to the components.

In contrast, a compressor is used to increase the pressure of air or gas, a reservoir acts as a storage tank for compressed air, thereby providing a supply buffer during varying usage demands, and an accumulator serves to store energy in a fluid system and help maintain pressure. While these components are integral to pneumatic systems, only the regulator is focused on reducing and regulating pressure to meet specific requirements.