500 GPM and Multi-pump Video
Systems with two or more pumps in different locations can be controlled with Cycle Stop Valves. These are ways of controlling multiple pumps that can be done at the pump locations with a simple pressure switch. There are no wires or radios connecting these pumps together. When the system requires more flow, more pumps come on to supply the need. As flow in the system decreases, pumps go off when they are no longer needed.
An example would be multiple pumps in different location and pumping into a common distribution system. In these systems each pump must have it's own Cycle Stop Valve, check valve, pressure switch, and small pressure tank. The pressure settings can be 5 PSI to 10 PSI between pumps. Adjustments for elevation differences must be made. If one of the pumps is 23' in elevation below another pump, the lower pump will read 10 PSI higher than the other pump. If the lower pump is required to operate the system at 50 PSI, the setting at the pump would be 60 PSI. The opposite would apply for a pump that is higher in elevation than another.
If there are no differences in elevation of the pumps on the system, pressure can be adjusted as follows. Requiring 50 PSI minimum to operate the system the largest pump is set to come on at 50 PSI. That pumps Cycle Stop Valve it set to maintain the 50 PSI and the pressure switch shuts the pump off at 55 PSI. The next smaller pump, which is a mile from the larger pump, is set to come on and the Cycle Stop Valve maintains 55 PSI. When the system pressure increases to 60 PSI this pump is shut off. A third and smaller pump still a distance from the other two pumps set to start at 60 PSI and go off at 65 PSI.
Pressured up to 65 PSI the system is shut off. When water is used anywhere in the system, the pressure drops to 60 PSI starting the smallest pump. The Cycle Stop Valve on the smallest pump is set to maintain 60 PSI. As long as there is 5 GPM being used in the system its' Cycle Stop Valve holds at a steady 60 PSI. When usage in the system increases beyond the capability of the small pump, pressure will decrease to 55 PSI and the second or medium size pump is started. As long as these two pumps can supply the demand, pressure remains at 55 PSI. When more water is required the pressure will drop to 50 PSI starting the third pump. With all three pumps running pressure will remain at 50 PSI as long as demand stays within the combined output of the three pumps.
When the demand decreases to a flow that can be produced by the two smaller pumps, pressure increases to 55 PSI and the third pump is shut off. Decreasing demand until the smallest pump can supply the flow will increase pressure to 60 PSI, which shuts off the second pump. If flow can be reduced to zero demand the small pump will slowly fill the system to 65 PSI and the last pump is shut off.
Many pumps can be brought on using 5 PSI to 10 PSI between pumps. When there are even more pumps in the system two ways of setting the pressures are possible. One way is for each pump to have only 3 PSI between on and off. For every 3 PSI drop in the system pressure another pump is started. Pumps can also be brought on in groups. Every time the system pressure drops 5 PSI a group of three or five pumps is started. These two ways of control will work with systems that have ten, twenty, or even more pumps.
Multiple Pump Systems
Multiple Pumps in Different Locations with Cycle Stop Valves