The invention of the pump itself was a major breakthrough for mankind. It significantly simplified the supply of normal water. With growing demands for a well balanced water supply, largely free from pressure fluctuations, and at the same time increasing demands on the energy efficiency of buildings, pumps are actually making their contribution as booster pumps. What their task is, how they function and what pressure switches do along the way is explained briefly and succinctly in the following paragraphs.
What are booster pumps needed for?
A booster pump increases low water pressure and, with that, improves the flow rate. It provides an extra boost to bring the water pressure to the desired level. Booster pumps are often used in pipelines to increase the pressure therefore to move the liquid along to another pump, and also for pumping in residential houses or large commercial buildings. An expansion vessel can extend a pressure booster system. Through the use of such an expansion vessel, the water pressure is likewise stabilised and therefore improved.
Booster pumps in operation
The figure gives a synopsis of the various measuring points within a pressure booster system:
1 Input pressure ? Pressure
2a Dry run protection ? Pressure
2b Dry run protection ? Level
3 Output pressure ? Pressure
4 Pump performance ? Differential pressure
How does a booster pump work?
Booster pumps are selected based on application demands. Rather than selecting one large pump, consider selecting multiple pumps with smaller horsepower. Booster pumps have an impeller that moves water that will come in through the inlet and exits through the outlet. A motor makes the impellers spin. The pumps differ in how they draw the water in and push it out. pressure gauge octa of them work with a spinning propeller, others use an oscillating diaphragm or other pump principles.
What do mechanical pressure switches in booster pumps do?
The mechanical pressure switches in booster pumps are employed for the direct control/monitoring of safety functions in order to protect pumps with insufficient input pressure against dry running. An example of here is the WIKA PSM-520 pressure switch.
How do mechanical pressure switches work?
The pressure part of the switch is really a resilient bellow which works against a spring mechanism having an adjustable pre-load force. On the spring mechanism there is a contact arm for actuating the change-over switch contact. The switch is actuated when the force generated by the pressure in the pressure element is higher than the set pre-load force.
Note
Further information on the many measurement solutions which you can expect you for pumps and systems are available on the WIKA website. Assuming you have any questions, your contact will gladly help you.
Also read our articles
Mechanical pressure switches: So how exactly does one set the switch point?
Mechanical vs. electronic pressure switches: Functionality
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