I have a shallow bored well that I use specifically for watering my garden. It typically works great, but occasionally loses its prime and I have to prime it manually. Because it does not have an incredible amount of volume to be able to pump it can run dry fairly quickly in dry times.
When it loses its prime the pump continuously runs dry until I notice it is not working an prime it and fix it.
What id like to do is put a pressure sensor somewhere in the water line and connect it to an arduino. If the pressure drops below a certain psi, have the arduino close the irrigation valve (turn sprinklers off) until the pressure is above a certain point and then it can open the valve back up once pressure is above a set point.
This seems fairly straight forward, but are there inexpensive water pressure sensors that I can purchase that work reliably with arduinos up to around 60 psi?
Also, I’d like to be alerted some how if the pressure dropped. It is too far for wifi to reach. Is there any simple long distance wireless technology available to send a signal back to my house (another arduino or esp device 200 yards away) that I could then relay the signal to my email?
I appreciate any help/and better ideas that I have!
60 psi = 4.14 bar, that is a lot. Are you sure ?
The water tap in a house in the Netherlands has 2.5 bar. For a garden it is often not that much.
There are cheap pressure transducers with a "industrial" look. They should work if you don't care about accuracy. A pressure transducer with a output of 0.5 ... 4.5V is easier to connect to a Arduino then a pressure transducer with a 0...20mA output.
200 yards = 183 meters. Most modules are for 10 meters. Do you have Wifi there ?
What you should try to create is a tank level gauge. They are common and there are lots of examples online. Many use a standard fuel tank level sender, some use ultrasound
Once the pressure drops in the line the error has already occurred.
A foot valve won’t work as the well is running dry and the pump is essentially pumping all the water through and losing prime that way. The foot valve will only prevent losing a prime from back flow of water into the well unless I am mistaken.
What I am thinking is if I have the 40/60 psi pressure switch the pump turns on at 40 psi. It can’t keep up and the pressure slowly lowers until it pumps its self dry. If I have the psi sensor turn the sprinkler off at around 20 psi (before losing prime) the pump still has water (primed) and is able to recover. Once the pressure is back up to 60 psi the arduino can allow the sprinkler to come back on.
I don’t need incredible accuracy just close. I see several pressure transducers on Amazon for less than $20. Wonder if they would work?
Ultrasound can be used in different ways and is often mounted on the outside of tanks but you can get sensors for the inside that essentially tell you distance from the top to the fluid level. They act like car reversing sensors. I think your pressure solution is wrong. Your problem is not pressure it is low water level. Your pressure system will just cycle the pump off and on until it manages to run dry. Best to deal with the source problem which is that the water level drops below that of the pump intake.
Hardware solution: dig bigger well
Software solution: detect water level and cut off pump when too low.
I understand what you’re saying. And I think if the well itself becomes too low (dry) and the pipe that is down in the well comes out of the water inside the well and sucks air in it may would cycle until it lost its prime even with my pressure sensor cutting the sprinkler off at 20 psi (or whatever was determined necessary).
However, I’m not sure this is what is happening, but I don’t know. The only “tank” I have to use for determine the water level is the blue pressure tank located beside the well. It is sealed with a bladder. I don’t want to go inside it with a sensor and I am a bit Leary of how well an ultrasound sensor could work outside that blue tank with such a small capacity in the loud environment.
Because pressure is based on volume, in my mind, if the volume goes down so that the pressure can not maintain the 20 psi i have set, the sprinklers will turn off (before getting too low and sucking air and losing prime). The pump will continue to run with sprinklers off until it gets back up to the normal psi the pressure switch cuts off at (more volume). Perhaps if the pressure gets that low I code some delay period to allow for recovery?
I’m not sure the water level of the well is getting below the foot of the well pump causing it to lose its prime or the volume of the water being pulled by the sprinklers is so demanding the pump can’t keep up. Although I’m not sure this would cause the pump to lose its prime?
I don’t know lol I’m just thinking out loud. Sorry if it doesn’t make sense.
I don’t have one. It would have to be located just above the foot valve on the well pump suction pipe I suppose?
No, there are a few ways to lose the prime in your pump.
1 the foot valve fails and pump when off can not prevent leakage of water back down the pipe into the well and eventually air
2 the well dries up and the pump sucks air
3 there is some other leak in the system at or below the pump which allows air in which will eventually create an air lock at the pump
The pressure of water your pump produces has nothing significant to do with the well. Your pump should be able to maintain its pressure setting even if starting to suck air so by the time the pressure drops there is air in the pump (that is why the pressure drops) and it is too late.
The tank is just a bladder for buffering the pressure as you can’t hold pressure in a non compressing fluid
The pump should work fine and with no loss of pressure even if you cut the main pipe from it and spray maximum amount of water all over yourself
Either your original post is correct or you need to check your valve and plumbing. If it is correct your plan is wrong IMO
It doesn’t lose its prime sitting. So that should eliminate foot valve problem. Leak below the pump seems to be the same issue as foot valve leaking to me. So I would assume I’m pumping well dry. Putting a float switch down inside the well itself could be an option I guess but I don’t really want to pull my pipe out it’s a pain. I replaced the foot valve about a year ago.
I suppose I could run it until it runs dry and drop a string down in it to measure where the level is. Then drop a float switch down with a string just above that level to cut off if the level gets below this?
You could make your own switch. A ball that floats. Attach a string to it and send it down the well. When floating there will be no tension on string. When hanging it will have tension which can easily activate a switch.
Depends on the well. I thought you said it was shallow
It’s a bored well. I guess shallow probably wasn’t the right word. I’d guess it’s 20 - 25’ or more to the bottom. I was comparing it to my drilled well.
The ball idea may work. I was thinking something like on a sump pump that has the switch built in. Just drop it down the well with the wires until it floats.
IF you are only using the well for garden watering, then you must be turning on the pump to begin the watering.
The simple solution is to go to a local hardware store and get a manually operated pressure switch and wire it in series with the motor power. I use exactly that to stop my irrigation motor if it runs out of water. Just hold the manual switch lever to start the motor and the water pressure will hold the switch closed. If the pressure ever drops, the circuit will open.
No other devices, including an Arduino are necessary.
What type of pump, self priming, shallow well jet, deep well jet? Depth of well? Depth of foot valve? Post link to pump datasheet or brand name and exact part number.
