What aspect of direct-operated regulators affects their control quality significantly?

The control quality of direct-operated regulators is significantly affected by their sensitivity, particularly in the context of how accurately and promptly they respond to pressure changes. High sensitivity in these regulators enables them to detect even minor fluctuations in pressure and adjust the valve position accordingly to maintain the desired output pressure. If the sensitivity is poor, the regulator may not respond adequately to pressure variations, leading to instability and erratic performance. This results in suboptimal control quality because the regulator is unable to maintain steady and precise pressure levels over time.

Other factors, like pressure regulation, temperature sensitivity, and flow dynamics, play a role in the overall functioning of regulators but may not directly impact the immediate responsiveness and control quality as dramatically as sensitivity does. For example, while temperature sensitivity can influence how a regulator performs under varying thermal conditions, its fundamental ability to accurately regulate pressure hinges more on its sensitivity. Therefore, poor sensitivity is a critical aspect that directly influences the control quality, making it essential for effective regulation.