BoosterpaQ®- Hydro MPC

9.5.3 Control mode (2.1.2)Open loopIn open-loop control, the pumps run at a fixed speed.The pump speed is calculated from the performance set by theuser (0-100 %). The pump performance in percentage isproportional with the flow rate.Open-loop control is usually used when the booster system iscontrolled by an external controller which controls theperformance via an external signal. The external controller couldfor instance be a building management system connected to theHydro MPC. In such cases, the Hydro MPC is like an actuator.See figs 22 and 23.Fig. 19Control modeDescriptionThere are two control modes, namely closed and open loop.Examples:Closed loopThe typical control mode is closed loop where the built-in PIcontroller ensures that the booster system delivers the dischargepressure required (setpoint). The performance is based on thesetpoint set for closed loop. See figs 20 and 21.TM04 6194 5009Fig. 22 Booster system with external controller (open loop)Flow rate [gpm]TM03 2232 3905TM03 2231 3905Fig. 2305Flow rate [gpm]Regulation curve for open loopInput [%] fromexternal controllerTM03 2391 3607Fig. 20Booster system controlled by built-in PI controller(closed loop)100SetpointFig. 21P [ps ]Regulation curve for closed loopTime [sec]Setting via control panel1. Mark the Operation menu with .2. Mark Further settings with or , and press .3. Mark Control mode with or , and press .4. Select Closed loop with or , and press .5. Set the setpoint. See sections 9.5.4 Setpoints (2.1.3) and9.5.1 Operation (2).TM03 2390 41057550255Fig. 2450 70.786.6 100Flow ratePump 1Pump 2Pump 3Pump 4Input [%] fromexternal controllerRegulation curve for Hydro MPC-E in open loopTM03 9977 480725