Microcontroller Based Irrigation System Engineering Essay

Abstraction
The Microcontroller based irrigation system is an advanced method used to H2O the workss on a regular basis when we are out of station.
The system makes usage of a microcontroller IC AT89C51, OP-AMP LM324 and associated circuitry. Microcontroller is preprogrammed and do the necessary stairss to exchange ON and OFF the motor depending upon whether the dirt is dry or non as indicated by the detectors. The OP-AMP is configured here as comparator.

The Microcontroller is used to command the whole system. It monitors the detectors and when more than two detectors sense the dry status so the microcontroller will exchange on the motor and it will exchange off the motor when all the detectors are in moisture. The microcontroller does the above occupation it receives the signals from the detectors, and this signals operated under the control of package which is stored in ROM
MICROCONTROLLER
89C51
SENSOR 1
SENSOR 2
SENSOR 3
SENSOR 4
Motor
Relay
Power SUPPLYBLOCK DIAGRAM
5V 12V
BLOCK DIAGRAM DESCRIPTION
( I ) POWER SUPPLY
Ninety-nine regulators are various and comparatively cheap and are available with characteristics such as current/voltage boosting, internal short circuit current modification, thermic closure and natation operation for high electromotive force applications. The regulated circuit is used to keep changeless end product degree. The incorporate circuit regulator, sometimes called the three terminal regulators contains the circuitry for mention beginning mistake amplitude control device and overload protection all in a individual IC bit. They are connected between end product of a filter and input to the burden.
The 78xx series consist of three terminal +ve electromotive force regulators. With equal heat droping they can present end product current in surplus of 1A. For proper operation, there should be a common land between the input and end product electromotive force.
As per the Indian criterions, the supply through the brinies is 230 Vs, 50 Hz Ac. For this undertaking, the power demands are +5V and +12V District of Columbia electromotive force degrees
By sing the current demands of the assorted ICs and the loading effects of the different current drawing elements used in this undertaking, the entire current demand was found to be about 1 A.
So we use a 12-0-12V, 1 A transformer to step down the brinies voltage to 12 V ( rms ) . The secondary of the transformer is fed to a rectifier circuit consisting of 1N4007 power rectifying tubes for change overing Ac to dc V. The pulsating end product therefore obtained has to be filtered to acquire the steady District of Columbia electromotive force. A capacitance filter of 2200 microfarads, 25V and 0.1 microfarads are used. Using regulator IC 7805 the needed electromotive force degree is obtained.
Here we have used 78xx series regulator which are three terminal, positive fixed electromotive force series regulators.
MICRO CONTROLLER
The microcontroller used is AT89C51. It is a low power, high-performance, CMOS
8- spot microcontroller with 4K Bytes of Flash programmable and effaceable read merely
memory.
Port1 of 89C51 Acts of the Apostless as an input port here.The end product of four comparators are fed to port1 ( Internet Explorer to P1.0, P1.1, P1.2, P1.3 ) . When to or more inputs are high, Internet Explorer for the spot combinations 0011,0101,0110,0111,1001,1010,1011,1100,1101, 1110,1111 the microcontroller will turn ON the motor.It will turn OFF the motor merely if all the inputs at Port1 is low Internet Explorer for the spot combination 0000.The microcontroller is pre-programmed to make this undertaking.
Detector
The detector parts are built utilizing OP-AMP IC LM324.The LM 324 series consists of four independent high addition, internally compensated operational amplifiers which are designed specifically to run from a individual power supply over a broad scope of electromotive forces. OP-AMP IC is configured here as a comparator. As shown in the circuit diagram stiff Cu wires are inserted in dirt and one terminal of each of these wires are connected to the negative terminus of the op-amp. When dirt is wet, its conduction will be high and end product of the comparators will be low. When the dirt is dry, the conduction will be low and the comparator end product will be high. The end product of these comparators are fed to the microcontroller.
Relay
Relaies are widely used to command devices that draw big current. A relay is a switch whose terminuss called contacts are unfastened and closed by an electromagnet. We normally use mechanical or solid province relays. The control circuitry for both of these types of relays is electrically isolated from the existent switch. When the current is passed through the twist of the electromagnet, the ensuing force actuates a metallic relay that causes one or more contacts to open and shut. The lever called armature is attached to the spring, so that when the current in the twist is removed, the spring force retraces the armature.
The twists in the relay is called spiral and it is said to be energized when current flows through it. The switch contacts that are controlled by relay are called usually unfastened or usually closed harmonizing to the status when they are energized. Thus a usually unfastened contact stopping points and a usually closed contact opens when energized. The chief advantage of the relay is that the contacts can be designed to exchange a heavy current in and out of a circuit when merely a little current is supplied to or disconnected from the spiral.
Here a 12V relay is used.The microcontroller bend ON and turn OFF the motor through this relay.
Motor
We are utilizing a 12V, DC motor to demo the working. For pumping the H2O an AC motor may be used.This motor can be drived utilizing the relay.
CIRCUIT DIAGRAM
Working
The undertaking presented here is an automatic irrigation system.It uses microcontroller AT89C51, op-amp LM324 and associated circuitry.
The power supply required for the microcontroller,5V can be either taken straight from a District of Columbia beginning and if merely Ac is available, so it can be rectified, filtered and the regulated 5V can be obtained with the assistance of power supply unit which is provided here.
The op-amp LM324 is configured as a comparator.There are four built-in units in it and associated with each unit we will infix two Cu wires in the soil.One terminal of these wires are in the dirt and the other terminal of one wire is connected to the supply say 5V and the 2nd wire is connected to the comparator ‘s inverting terminal.When the dirt is wet its conduction will be high and 5V will make the inverting terminus through the wires inserted in dirt. Consequently the ouput of that peculiar comparator will be low.If the dirt is dry its conduction will be low and the comparator will give a high end product.
As already mentioned there are four comparators and the end product of all these comparators are fed to Port1 ( Internet Explorer to P1.0, P1.1, P1.2, P1.3 ) of the microcontroller.
Port1 of 89C51 Acts of the Apostless as an input port here.When to or more inputs are high, Internet Explorer for the spot combinations0011,0101,0110,0111,1001,1010,1011,1100,1101,1110,1111the microcontroller will turn ON the motor.It will turn OFF the motor merely if all the inputs at Port1 is low Internet Explorer for the spot combination 0000.The microcontroller is pre-programmed to make this undertaking. The microcontroller bend ON and turn OFF the motor through a 12V relay.
SOFTWARE PART
Flow chart
Start
If power supply on
Stop
Read Port P1 as input port
Port P1 = FFH
A = P1
If
A = 0000
Motor OFF
If
A = 0001
Motor OFF
Nitrogen
Yttrium
If
A = 0010
Motor OFF
Nitrogen
Yttrium
Yttrium
A
A
A
Yttrium
Nitrogen
A
Bacillus
Nitrogen
If
A = 0100
Motor OFF
Yttrium
If
A = 1000
Motor OFF
Nitrogen
Yttrium
A
A
Nitrogen
Bacillus
Motor ON
If
A = 0000
Yttrium
Nitrogen
Motor OFF
A
PCB FABRICATION
PCB DESIGN
PCB design of the circuit was implemented utilizing DIP TRACE. Initially the schematic of the circuit was drawn. The necessary PCB footmarks were given, thereby stipulating the constituent size and spacing. After giving the footmarks a new list was created.
Rooting process was done utilizing the DIPTRACE PCB LAYOUT package. The net list was loaded and constituents spacing done consequently. Using the Auto rooting option, rooting was done. The possible connexions were made utilizing Auto rooting and the staying connexions were done manually utilizing jumpers.
PCB FABRICATION
After the PCB design stage, PCB fiction was done. The way was drawn on a circuit board utilizing a C paper and the mirror image obtained was painted. The board was etched by dunking it in a extremely concentrated Ferric Chloride and after etching, the staying pigment was removed. The continuity of all waies was checked and so the constituents were placed and soldered. After supplying the necessary jumpers besides the circuit was tested.
Bonding
Soldering is the fall ining together of two metals to give physical bonding and good electrical conduction. It is used chiefly in electrical and electronic circuitry. Solder is a combination of metals, which are solid at normal room temperatures and go liquid at between 180 and 200A°C. Solder bonds good to assorted metals, and highly good to Cu.
Soldering is a necessary accomplishment you need to larn to successfully construct electronics circuits. It is the primary manner how electronics constituents are connected to circuit boards, wires and sometimes straight to other constituents.
To solder you need a bonding Fe. A modern basic electrical bonding Fe consists of a warming component, a soldering spot ( frequently called the tip ) , a grip and a power cord. The warming component can be either a opposition wire lesion around a ceramic tubing, or a thick movie opposition component printed onto a ceramic base. The component is so insulated and placed into a metal tubing for strength and protection. This is so thermally insulated from the grip. The heating component of soldering Fe normally reaches temperatures of about 370 to 400A°C ( higher than needed to run the solder ) . The soldering spot is a specially molded piece of Cu plated with Fe and so normally plated with chrome or Fe. The tip planting makes it really immune to aggressive solders and fluxes.
The strength or power of a bonding Fe is normally expressed in Watts. Irons by and large used in electronics are typically in the scope 12 to 25 Watts. Higher powered Fe will non run hotter, but it will hold more power available to rapidly replace heat drained from the Fe during soldering. Most chainss are available in a assortment of electromotive forces, 12V, 24V, 115V, and 230V are the most popular. Today most research labs and fix stores use soldering chainss, which operate at 24V ( powered by isolation transformer supplied with the soldering Fe or by a separate low electromotive force mercantile establishment ) . You should ever utilize this low electromotive force where possible, as it is much safer. For advanced bonding work ( like really bantam really sensitive electronics constituents ) , you will necessitate a soldering Fe with a temperature control. In this type of soldering chainss the temperature may be normally set between 200 degC and 450 degC. Many temperature-controlled soldering chainss designed for electronics have a power evaluation of around 40-50W. They will heat fast and give adequate power for operation, but are automatically little ( because the temperature accountant stops them from overheating when they are non used ) .
You will on occasion see gas-powered soldering chainss which use butane instead than the brinies electrical supply to run. They have a catalytic component which, one time warmed up, continues to glow hot when gas passes over them. Gas-powered soldering chainss are designed for occasional “ on the topographic point ” usage for speedy fixs, instead than for mainstream building or assembly work.
You need to be careful in soldering because most electronic constituents are delicate, and heat sensitive. Normally our biggest concern is heat. Low plenty soldering temperature and short plenty soldering clip keeps constituents in good form. Electronicss constituents are designed so that they can take high temperatures on their contacts/wires for some clip without harm ( to defy the bonding ) . Prolonged exposure to high temperature will heat up when interior of the constituent can do harm to it.
Presently, the best normally available, feasible, and safe solder metal is 63/37. That is, 63 % lead, 37 % Sn. It is besides known as eutectic solder. Its most desirable feature is that its solids ( “ pasty ” ) province, and its liquid province occur at the same temperature — 361 grades F. The combination of 63 % lead and 37 % Sn thaws at the lowest possible temperature. Nowadays there is inclination to travel to utilize lead free solders, but it will takes old ages until they will catch on normal soldering work. Lead free solders are nowadays available, but they are by and large more expensive and/or harder to work on than traditional solders that have lead in so,
The metals involved are non the lone things to see in a solder. Flux is critical to a good solder articulation. Flux is an aggressive chemical that removes oxides and drosss from the parts to be soldered. The chemical reactions at the point ( s ) of connexion must take topographic point for the metals to blend. RMA-type flux ( Rosin Mildly Active ) is the least corrosive of the readily available stuffs, and provides an equal oxide remotion.
In electronics a 60/40 fluxed nucleus solder is used. This consists of 60 % Lead and 40 % Tin, with flux nucleuss added through the length of the solder.
There are certain safety steps which you should maintain in head when soldering. The Sn stuff used in soldering contains unsafe substances like lead ( 40-60 % of typical bonding Sns are lead and lead is toxicant ) . Besides the assorted from the soldering flux can be unsafe. While it is true that lead does non zap at the temperatures at which soldering is typically done, particulate affair is merely every bit unsafe as exhausts would be in footings of toxic condition and there is particulate lead nowadays to some extent in the exhausts from your flux.
When soldering maintain the room good ventilated and utilize a little fan or fume trap. A proper smoke trap or a fan will maintain the most pollution off from your face. Professional electronics workshops use expensive fume extraction systems to protect their workers ( needed for working safety grounds ) . Those fume extraction devices have a particular filter, which filters out the unsafe exhausts. If you can link a canal to the end product from the trap to the exterior, that would be great.
Always wash custodies prior to smoke, feeding, imbibing or traveling to the bathroom. When you handle soldering Sn, your custodies will pick up lead, which needs to be washed out from it before it gets to your organic structure. Do non eat, imbibe or smoke whilst working with soldering Fe. Do non put cups, spectacless or a home base of nutrient near your working country.
Wash besides the tabular array sometimes. As you solder, at times there will be a spot of ptyalizing and sputtering. If you look you ‘ll see bantam balls of solder that shoot out and can be found on your soldering tabular array.
The bonding Fe will last longer with proper attention. Before and during usage wipe the spot on a moist sponge. Most bench bases incorporate a sponge for this intent. When utilizing a new spot, use solder to it as it heats up. Always maintain a hot Fe in a bench base, or suspended by the hook, when non in usage. Bend of the Fe when you do non utilize it. Sporadically take the spot and clear off any oxide build up. Regularly check the brinies lead for Burnss or other harm ( alteration mains lead if necessary ) .
PCB LAYOUT
Cost Appraisal
SL NO.
Components
Specification
Rate
Measure
Cost
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
Resistors
Diodes
Capacitors
Crystal
Op-amp
Microcontroller
IC Base
Transistor
Transformer
Relay
DC Motor
Regulator IC
PCB fiction & A ; Soldering
LED
Casing
10 K
100 K
220 I©
2.2k
1N4007
2200 AµF
0.1AµF
47AµF
10AµF
8 MHz
LM 324
AT89C51
14 pin
40 pin
BC 107
12-0-12
12 V
12V motor
Intelligence community 7805
10 PS
10 PS
10 PS
10 PS
20 PS
50 PS
50 PS
50 PS
50 PS
Rs 5.00
Rs 18.00
Rs 58.00
Rs.2.00
Rs.10.00
Rs 1.00
Rs.70.00
Rs.8.00
Rs.70.00
Rs.5.00
Rs.250.00
Re.1.00
Rs.20.00
9
4
5
4
3
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
4
1
90ps
40ps
50ps
40ps
60ps
50ps
50ps
50ps
50ps
Rs 5.00
Rs.18.00
Rs.58.00
Rs.2.00
Rs.10.00
Rs.1.00
Rs.70.00
Rs.8.00
Rs.70.00
Rs.5.00
Rs.250.00
Rs.4.00
Rs.20.00
TOTAL = Rs..526.00
Decision
Here we introduce a simple and cheap irrigation system. The hardware subdivision consists of an op A and a microcontroller circuitry. The unit can be easy implemented in our houses for little graduated table every bit good as in farms for big scale irrigation.
Bibliography
Mentions
The 8051 Microcontroller and embedded systems – Muhammad Ali Mazidi
Op As and Linear Integrated circuits – Ramakand Gaykwad
Web sites
www.atmel.com
www.8051projects.info/proj.asp? ID=40
Plan
# INCLUDE & lt ; SFR55A.INC & gt ;
MOTOR BIT P2_0
MOTOR_LED BIT P2_1
DRY BIT P2_2
WET BIT P2_3
CSEG AT 0
ORG 00H
Start:
MOV P1, # FFH
MOV A, P1
CJNE A, # 00H, NEXT_VALUE
ACALL MOTOR_OFF
NEXT_VALUE:
CJNE A, # 01H, NEXT_VALUE1
ACALL MOTOR_OFF
NEXT_VALUE 1:
CJNE A, # 02H, NEXT_VALUE2
ACALL MOTOR_OFF
NEXT_VALUE 2:
CJNE A, # 03H, NEXT_VALUE3
ACALL MOTOR_ON
NEXT_VALUE 3:
CJNE A, # 04H, NEXT_VALUE4
ACALL MOTOR_OFF
NEXT_VALUE 4:
CJNE A, # 05H, NEXT_VALUE5
ACALL MOTOR_ON
NEXT_VALUE 5:
CJNE A, # 06H, NEXT_VALUE6
ACALL MOTOR_ON
NEXT_VALUE 6:
CJNE A, # 07H, NEXT_VALUE7
ACALL MOTOR_ON
NEXT_VALUE 7:
CJNE A, # 08H, NEXT_VALUE8
ACALL MOTOR_OFF
NEXT_VALUE 8:
CJNE A, # 09H, NEXT_VALUE9
ACALL MOTOR_ON
NEXT_VALUE 9:
CJNE A, # 0BH, NEXT_VALUE11
ACALL MOTOR_ON
NEXT_VALUE 11:
CJNE A, # 0CH, NEXT_VALUE12
ACALL MOTOR_ON
NEXT_VALUE 12:
CJNE A, # 0DH, NEXT_VALUE13
ACALL MOTOR_ON
NEXT_VALUE 13:
CJNE A, # 0EH, NEXT_VALUE14
ACALL MOTOR_ON
NEXT_VALUE 14:
CJNE A, # 0FH, NEXT_VALUE10
ACALL MOTOR_ON
NEXT_VALUE 15:
AJUMP START
MOTOR_ON:
SETB MOTOR
SETB WET
CLR MOTOR_LED
CLR DRY
RET
MOTOR_OFF:
CLR MOTOR
SETB DRY
CLR WET
SETB MOTOR _LED
End