Simple Well Pump Controller
Simple Well Pump Controller
Find out how to automatically get water from the well into a header tank
water | electronics | electric circuitIn this article we will look at how a simple system using
float switches and
relays can be put together to automate the process of getting water from a well, spring, or stream into a
header tank ready for use. This system design uses
no electronics, is very cheap and simple to put together, and it is reliable in operation.
In our article
Simple Sump Pump Controller we put together an electronics-free system to
automatically pump out a sump pit when it gets full. One
float switch at the top of the pit detects when it is full (turning on the pump), and a second near the bottom detects when it has been emptied (turning off the pump). If you have not already done so, you may wish to read that article first so you understand the concept behind the system described here.
Well Pump Control System Design
To
automatically fill a header tank from a well, we need to
reverse the configuration of the sump pit emptying system so that a float switch at the bottom of the header tank detects when it is empty starting the
pump, and then a float switch at the top of the tank detects when the tank is full stopping the pump.
Pictured above is the
connection diagram for this modified system. The
float switches are configured such that they sit horizontally when they are not in water, and float upwards when they are in water: in water = switch open, out of water = switch closed.
When the water level in the
header tank falls below the lower float switch (LFS), that switch closes
energising the
relay. Since the upper float switch (UFS) must also be out of water and closed, the following connection is made:
battery 12V -> UFS -> relay COM -> relay NO -> relay coil
Therefore, the relay is
latched - i.e. will remain energised - for as long as the UFS remains closed (which it will as long as it is not under water). When the level of the water pumped up from the well finally reaches up above the UFS, it opens that switch breaking the connection between the
battery and the relay coil and so turns off the pump.
Connecting the Pump
A
12V pump is connected to his system via a second
relay as pictured below:
If a
mains powered pump is to be used, then a
qualified electrician must do the wiring (or at least check it and sign it off) and ensure that everything is correctly earthed and insulated etc.
Well Pump Control Circuit Board
Pictured below is an example
circuit board for this system. Three LEDs (and electronics) have been added for visual confirmation of system status - red lights when the header tank is full, yellow lights when there is water in the header tank, and green lights when the pump is on.
Note that adding the
LEDs made this circuit much more complicated since it quite difficult to make an LED light up when a switch is open (which the float switches are when they are under water). Without LEDs
no electronics would have been required and the board would have been much simpler.
If you would like to have a board such as the one pictured above put together, please contact
neil@reuk.co.uk with full details of your requirements.
Other Uses for this System
This simple system is ideally suited for use with
irrigation,
rainwater collection, and
rainwater toilet flush projects. In any situation in which a tank or cistern has to be automatically filled so it never runs dry, this design can be used.
Article Last Modified: 08:58, 5th Aug 2008
Recommended Related Articles
People who read this article also enjoyed the following articles:
Simple Sump Pump ControllerPut together a sump pump controller with two float switches and NO electronics
Article Last Modified: 08:58, 5th Aug 2008water | electric circuit | electronicsSolar Water Heating Pump ControllerBuild an electronic pump controller for a solar water heating system
Article Last Modified: 11:33, 9th Jul 2007water | solar | electronicsPermanent Magnet GeneratorBuild a wind or water power system with around a PM Generator
Article Last Modified: 11:44, 21st Jul 2008wind | hydroPVC Wind Turbine BladesLearn how to make your own PVC wind turbine blades
Article Last Modified: 15:16, 19th Aug 2008windDIY 2kW Wind TurbineRead about a home built 2kW wind turbine constructed from scrap
Article Last Modified: 08:46, 4th Oct 2007wind | recyclingFloat Switch Water Level MeasurementFind out how to use float switches in renewable energy applications
Article Last Modified: 12:07, 28th Jul 2008water | electric circuitWater Pump Hysteresis CircuitA simple circuit to prevent a pump being damaged by being turned on and off rapidly (multiswitching)
Article Last Modified: 14:54, 19th Nov 2007water | electronics | electric circuitMiniWind Wind TurbinesFind out more about the MiniWind range of wind turbines
Article Last Modified: 13:33, 1st Aug 2008wind | shoppingRainwater Toilet Flush SystemFind out how to put together a complete rainwater fed toilet flushing system
Article Last Modified: 15:16, 19th Aug 2008water | general | electronicsGreenhouse Heatsink Connection DiagramPutting together a solar powered greenhouse heatsink
system
Article Last Modified: 13:18, 30th Jun 2008solar | heating | general
|
|
£39.99 
