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Magnetic Switch Paired with Timer - Help Answered

Hi All,

I am a real newbie in electronics, and have been researching. I want to build a submersible pump, using (5 gallon bucket, a toilet flush valve and a pond pump -120 volts). What I need is some way to control the pump so its not running 100% of the time.

What I need is a Timer which would keep the pump running for X minutes and a magnetic switch which would activate the timer once the toilet flush valve is at a specific level.)

I dont know how to set this up, I found 555 timers on amazon but not sure which ones would serve to what I need

this one seems to be what i need but it is 12 volts


maybe this thing would work


Can someone recommend how to go about building something like that? Or maybe there is something similar already built?

Thank you very much!



4 years ago

hey I would recommend you to use an Arduino cause it will save you the trouble of buying other component except for a relay. I can give you exact details if you like this idea. You can find Arduino even for $10 on Amazon, which would be lesser than the price required for all the parts if using a 555 timer.


Reply 4 years ago

Hi Robo10302, would you mind telling me a little more about your idea? I am novice in electronics and have never used Arduino before.

Thank you


4 years ago

Hmm, subersible garden pumps come with a float switch.

You activate the pump and it stops once the tank is so empty the float no loger works and shuts the pump off.

I know Arduino is great but I don't understand why everyone sees them as a solution these days, it's like using a gaming PC to calculate your grocery bill where a calculator would be sufficient.

You can get nice and simple switching circuits ready to go as well.

A floating push rod would do exactly what you want : In the top position it switches the pump on (together with the manual switch), in the bottom position it switches the pump off.

If you do need a timer but hae no clue about the electronics get an adjustable toilet light timer - they are strong enough for a small pump and cost only a few bucks.

Easy to wire up too.


Reply 4 years ago

Hi Downunder35m, would you mind showing me what you mean by the the garden float switch, i could not find one in home depot maybe you can attach a link, or can you tell me more about the float rod/push switch? i really appreciate your feedback!


Reply 4 years ago

Only used Google to find a pic:

The switch is the ball on the side.

Not sure if you get similar switches just as a spare as the pumps are usually fully sealed.

But I got mine for less than 40 bucks at the hardware store.
You just connct them and when they get power they pump until the float hangs down again to switch the pump off, can be used a safety feature to stop the pump running dry or simply to switch it off when a tank is empty.
The push rod does the same only that you connect two switches outside the water.

One switch will do if you only want to shut the pump off once the tank is empty.

Think of it as a PVC pipe, sealed on both ends so it floats.
It is long enough to stick out of the water so it can activate a switch - either directly or with an added pin on the side of the pipe.
Like a float for fishing ;)