Fairchild

Pneumatic Relay

Model 14 Biasing Pneumatic Relay

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Designed for applications that require an output pressure that is the sum of a controlled input signal plus or minus a fixed bias, Fairchild’s Model 14 Biasing Pneumatic Relay provides versatility in its ability to provide either positive or negative biasing in a single unit. The output of the relay is the sum of the spring bias, set with the Range Screw, plus a pneumatic input signal. (Po = Ps + K); where Po is output pressure, Ps is signal pressure, and K is the combined spring constant.


Model 15 Positive Bias Relay

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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. The Fairchild Model 15 relay, available in several bias range configurations to meet a variety of output requirements, offers excellent sensitivity and high flow capacity in a small volume.


Model 22 Pneumatic Computing Relay

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The Model 22 Pneumatic Computing Relay is a highly versatile control valve designed to perform a number of specialized functions, including averaging, differential, inverting, and totalizing. This high quality unit, which offers up to four inputs as well as positive and negative biasing over a broad range, is available in several configurations to meet most application requirements.


Model 90 Low Pressure Selector Relay

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The Model 90 Low Pressure Selector Relay is designed to select the lower of two signal pressures to provide a continuous output pressure to a control device. The Model 90 is recommended for dead end or low flow service in critical applications such as control loops requiring precise, automatic monitoring of signal pressures.