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1. Pro vide Local control ()('the Bypaiss valve when (lie valve LOCAU REMOTE sw =itch is in <br />the LOCAL posil.ion. Allow valve control from the PLC when the switch is in the REMOTE <br />Position, <br />2. Provide a valve percent open position si; nai, and REMOTE signal to the PLC" <br />B, PLC Functions <br />1. Monitor the valve "percent open " position signal, and provide discrete OPEN and CLOSE <br />cotnnaands to the valve operator from tire: PLC. <br />2. Bypass valve position control <br />a. Provide a position controller (AUTO/ MANUAL) in the PLC; with "OpEW' and <br />"CLOSE" discrete outputs:, to conlrol the position of the Bypass Valve, Use the analog <br />valve position signal as the; controller .feedback. <br />h. "Computer Manna]" control: Allow the Operator to control the valve position by <br />entering a "percent open" setpoint when controller Manual is selected. <br />c. Auto Mode; The position of the valve is controlled by the output of the bypass line flow <br />P117 controller. <br />3. F3ppass lirrs l7oev caaratro1ler: <br />a. Provide a PLC .soft bypass line flow controller (AUTO /MANUAL) to control tlae now <br />in the bypass line using tile, bypass; line analog floe"," meter signal for glee controller <br />feedback. The controller output is a hyposs valve position setpoint.. <br />b, Computer 1 ,rnual: When Manual flow controller mode is selected allow the operator <br />to enter flow setpoint to the controller. <br />c, AUID ;t"fode: ah'hen the controller is pul into Auto mode, the; flow setpoint is switched <br />to the output of tlae Bypass Pressure controller. <br />4. Bypass line pressure controller: <br />a. Provide a PLC based PID controller for system pressure control when in By <br />lauass h"locle <br />using the system pressure analog signal as feedback. The output of the controller is ,a <br />flow setpoint to the [low controller. <br />b, Allow the Operator to enter to enter a Bypass pressure setpoint at the 14MI <br />5. Lraahle atttnrnatic hq aass caantrar1 when the Hallowing eonditions are rnou <br />a, Bypass Control is Enabled <br />h. All hooster pumps are OFF <br />