Digital water management system With Micro controller

Dear All,

I have decided to design a digital water management system for domestic usage, which includes

1.LCD Display-->to shows available water level in the domestic water tank in Liters

2.Automatic water motor

3.Three micro switches

4.RTC and temperature to Display Time 7 Temp: ( Optional )

5.Pressure Sensor ( To measure water level )

The source code for above system I can manege

My Question is,

I need to develop above system using software development life cycle

The point I need more help is, what is the design phase i should follow

Ex:

1.Finite state machine
2.Flowchart
3.
4.

It is greatly appreciated if you can provide examples

Please help
Thanks in advance

Although there are exceptions, finite state machines work best when there are logical input states and logical output states. In your case you have analog inputs and an LCD output so I would suggest a flowcharted method is the best route to follow. You can incorporate most of the functions in one microcontroller, I would recommend one of the PIC18F series with built in RTC and analog inputs to do most of the work. I use an 18F46J11 in a similar application, driving a four line LCD, controlling several 3-phase pumps (through an interface!) and monitoring five different temperature sensors.

Brian.

Dear Brian,

Thanks a lot for the grate advice

I would be much appreciated if can further advice about any software that can be used to create Finite state diagram

Dear Brian

Which design you are recommended for the my project in the attached PDF
I mean schismatic diagram in my attached
Please advice

Any of those designs will work but it really depends on how you connect the sensor to the water tank and how accurately you need to measure the level. It could be difficult to associate the level with the pressure unless you use the weight of the water inside the tank or use a sealed tube to measure displaced air presure. If the reading doesn't have to be very accurate it would be much simpler to use a conduction or capacitive sensor rather than pressure.

Brian.

betwixt said:

Any of those designs will work but it really depends on how you connect the sensor to the water tank and how accurately you need to measure the level. It could be difficult to associate the level with the pressure unless you use the weight of the water inside the tank or use a sealed tube to measure displaced air presure. If the reading doesn't have to be very accurate it would be much simpler to use a conduction or capacitive sensor rather than pressure.

Brian.

Click to expand...

I am using 500L tank and 35 feet height from the ground
Sensor fixed 6 feet height from the ground
Hose diameter is 1inch at the tank and reduced to .5cm at the sensor.

PA3040 said:

I am using 500L tank and 35 feet height from the ground
Sensor fixed 6 feet height from the ground
Hose diameter is 1inch at the tank and reduced to .5cm at the sensor.

Click to expand...

Hi PA,

Have not use those low cost mpx2010 sensors but this site , if you have not already seen it, seems to offer some good practical advise on using them ; see the comments at the bottom of the page.

**broken link removed**

Hi wp100,

Thanks for the reply

MPX2010 supports rage is 0 to 10kpa so my water tank weight is approximately 500Kg (500L), therefore I decided to use MPX5500 which supports 0 to 500kpi
Please let me know when you have more info

Hi,

Is not the 5500 too big as your min/max readings would only be a fraction of its full scale, so your results would be perhaps not as accurate ?

If my sums are correct -

35ft - 6ft = 29ft ( tanks actual internal height not mentioned)

29ft / 2.31 = 12.55 psi

12.55 psi / .145 = 86 kPa.

So would a mpx2102 be a more suitable, its rated at 100kPa but able to withstand a max of 400kPa
The mpx2202 is also there it you want that bit more capacity.