The Model 15 Positive Bias Relay is designed for applications that require an output pressure that is the sum of a controlled input signal plus a fixed bias. This pneumatic relay provides an output pressure that represents the input signal pressure plus a preset bias. Mathematically Po = Ps + K where Po is output pressure, Ps is signal pressure and K is the spring constant. This unit, available in several bias range configurations to meet a variety of output requirements, offers excellent sensitivity and high flow capacity in a small volume. The Fairchild Model 15 Pneumatic Biasing Relay is well suited to a variety of control applications, including range shifting, and tension control, and pressure control from a remote location.