Pneumatic Indicating Controller – Model 40 Controller

The Model 40 Pneumatic Controller automatically positions a valve or other final control element to maintain process pressure at the desired set point. As receiving controllers, they can control any process variable transmitted as a pneumatic signal. Standard models have proportional band adjustments for controlling processes where load changes are infrequent and can be corrected by the manual reset feature, standard in every controller. By a simple screwdriver adjustment, the standard proportional controller can be changed to two-position control action with adjustable differential gap. Model 40 Controllers are available with control modes of 100% proportional, 200% proportional plus reset and 300% proportional plus reset plus rate (PID) (for processes with frequent load changes). They not only satisfy ordinary control requirements, but are equally proficient in controlling processes with unfavorable characteristics.