pump control with float switch using relays


Thread Starter


I would like to know how can I control pump one float switch using relays. I have three pumps. only one float switch. we want to run two pumps together while float switch is enabled. third pump is stand by. same time pump should run by cyclic 1-2-3, 2-3-1, 3-2-1 like that. anybody have relay circuit diagram for this? if i will add one float switch how will be circuit design?

thank you.

Matthew Hyatt

My design time is billed at $60 / hr. A) do the design yourself and learn something or B) pay me to do it for you. a three pump alternating circuit with one acting as standby is not trivial and I do not work for free.

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To maintain a level with a float switch you need two switch points. Usually, if they are close you can have two switch points controlled by one float. So, you do need a high and low or a delay. One switch point will simply cycle itself to death.

You can have both pumps work at the same time from the same circuit. But, usually - a third switch point is used slightly above the pump on one. If the level hits that point - it will activate the second or backup pump.

Then to get the third pump going you will need an alternating relay. How this works is - it simply changes contacts each time it is energized. You would need two.

You can see the manual for the latching relay at: http://www.almegcontrols.com/operating_manual.htm and go to SSR1000. The manual explains the operation.

Thanks Bob Hogg