Select the compressor Nr. to operate according to the last compressor which was in operation: the other compressor is selected; Start the compressor; Wait until the water level switch to stop the compressor is triggered in the pressure vessel. If it is not triggered after 30 min (adjustable parameter), start the second compressor; Regulate the stop and start of the compressor according to the activation of the corresponding water level switches in the pressure vessel; When the compressor planned is not available (in "Manual" or "0" position or in default) the other available compressor shall start. The automatic particular control philosophy of starting a pump in automatic mode is as follows: Assure that the selector switch of the pump is in automatic mode; Alternate the pump to start according to the last pump which was in operation: the other pump is selected; that the positions’ switch of the gate valve downstream the pump is triggered on the "Close" position. If it is not triggered, launch a "close" order of the valve and wait until the positions’ switch is triggered on the "Close" position; Close the valve of the vacuum pipe for priming the pump; Start the pump at minimum speed (i.e. 60% of the rated frequency) and increase the speed gradually; Increase the until the discharge pressure sensor of the pump delivers a measured value equal to the minimum pressure according to the equation of the network curve ( = 2.7 bars, adjustable parameter); Open the gate valve downstream the pump and wait until the positions’ switch is triggered on the "Open" position; Another pump cannot be started before the end of this sequence; Begin the regulation phase: According to the water flow measured by the flow-meter, accelerates or decelerates the frequency controlled drive to reach the pressure of the set point calculated with the flow/pressure equation. This pressure is measured by the pressure sensor of the discharge main pipe. The set point is calculated every 30 s (adjustable parameter) and implemented with the Proportional/Integral/Derivative function of the PLC (PID controller);
Select the compressor Nr. to operate according to the last compressor which was in operation: the other compressor is selected; Start the compressor; Wait until the water level switch to stop the compressor is triggered in the pressure vessel. If it is not triggered after 30 min (adjustable parameter), start the second compressor; Regulate the stop and start of the compressor according to the activation of the corresponding water level switches in the pressure vessel; When the compressor planned is not available (in "Manual" or "0" position or in default) the other available compressor shall start. The automatic particular control philosophy of starting a pump in automatic mode is as follows: Assure that the selector switch of the pump is in automatic mode; Alternate the pump to start according to the last pump which was in operation: the other pump is selected; that the positions’ switch of the gate valve downstream the pump is triggered on the "Close" position. If it is not triggered, launch a "close" order of the valve and wait until the positions’ switch is triggered on the "Close" position; Close the valve of the vacuum pipe for priming the pump; Start the pump at minimum speed (i.e. 60% of the rated frequency) and increase the speed gradually; Increase the until the discharge pressure sensor of the pump delivers a measured value equal to the minimum pressure according to the equation of the network curve ( = 2.7 bars, adjustable parameter); Open the gate valve downstream the pump and wait until the positions’ switch is triggered on the "Open" position; Another pump cannot be started before the end of this sequence; Begin the regulation phase: According to the water flow measured by the flow-meter, accelerates or decelerates the frequency controlled drive to reach the pressure of the set point calculated with the flow/pressure equation. This pressure is measured by the pressure sensor of the discharge main pipe. The set point is calculated every 30 s (adjustable parameter) and implemented with the Proportional/Integral/Derivative function of the PLC (PID controller);