The Heating and Cooling 2-pipe Control with 2-position Valve and Proportional valve Module controls a 2-position valve and a proportional valve for either reheat or cooling. The module can be configured for DA-T, RA-T, or ZN-T control. The module is designed with temperature control, low limit control, and a Low OA Temperature mode. In addition to the proportional valve, this module is also designed to control a circulating pump. This module incorporates tracking the overridden value of the actual output object (AO, PAO). The module resets the PIDs to default tuning parameters if the Reset PID Tuning input is not Normal.
This module provides a second output that incorporates lead compensation to control devices. This function attempts to remove some of the dynamics of the control loop. This process results in forward-looking predictions and speeds up controller responses. The effect is similar to adding derivative action to the controller. Lead compensation is incorporated into most zone temperature control processes where oversized or nonlinear valves might be applied. For more information on the Lead Compensator block, see Lead Compensator in the Control category of the Logic section.