DIGITAL TIMER MULTI-PLUG

Executive Summary Problem StatementThe greatest problem that is faced in the resent era is over use of electricity because people are too busy and forget to switch off the wall plugs which are connected to appliances. The solution for this is to time how long the current flows to an appliance. Therefore a simple solution could be a plug that could be timed. This could provide the people with an advantage for them to select the required time. Rhetorical PurposeThis report gives a fully accounted detail of the product along with the background of the products that is the steps of the design and the cost of production.The purpose of this report is to show the people how this product helps them save time as well as electricity.Objective and backgroundPeople are too busy and forget to switch off bulbs or cell chargers or, our product The timer multi-plug, lets people time which appliance or electronic device works for how long, that is, the current supply to any particular product such as a mobile charger, could be cut down according to the time set on the timer.Methodology and experiment procedureIn order to solve the problem of overcharging/overuse and to save electricity. More research had to be done on how the components of The timer multiplug is fixed.The people who were involved in the research were Erandi, Sharunie, Sarujan, kogul and sithira.The timer plug might seem complicated, but, it was made with a single programmable arduino board, and few other components combined. The program for the arduino was written step by step, alterations had to be done at some points, and more background research had to be done to finalize the program.The PCB was make with the help of another person, where, he taught us how it was made, and the instructions were given to us.The finalization of the product was done, and it was successful.ConclusionThe objective of this product is to stop the current according to the time set, and we were was able to achieve this.

Implication of the organization The below table gives the cost of production:ItemPrice (LKR)

Arduino2000

LCD Screen450

PCB100

Power Pack380

Multi plug60

Plastic casing800

TOTAL3790

The total production cost was LKR: 3690, therefore the product will be a bit more expensive than the production cost, but this product could save more money by saving forgotten electricity.

Content

Introduction..04Background...05Design specification..09Tools and technics for design and Evaluation...11Preliminary design...14Discussion..20Conclusion.23References.23

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IntroductionThis project we carried out is related to the field of electrical and electronics. We thought of designing a multi-plug which can be controlled according to our desire and which basically means designing a multi-plug plug which can be controlled by time. As we know multi-plug is an electric device that allows more than one plug to connect to a single socket by containing multiple similar sockets; particularly for means electricity and over the decades we have considered the multi-plug as a very useful device not only in the field of electrical but also in our day to day lives. Yet people still had not thought about going to the next level of multi-plugs by adding a little more technology to it.There were many problems that led us to think far beyond a simple multi-plug which has been remained unchanged over the years. One of the most common problem was feeling lazy to get up (especially if youre involved in some important work) and go all the way up to the multi-plug which is fixed to the wall socket just to switch it off. Another issue was overcharging and overheating of electrical appliances like mobile phones due to the inability of switching off the multi plug at the proper time. This reason has even made electrical appliances blast causing danger to human lives as well. Also we thought if we could have a device to stop the current flowing to electrical appliances like the refrigerator during the peak hours of the day (that is usually in evening of day) it would reduce the cost of electricity thus saving money.Thereby these types of above mentioned problems gave us the idea of combining the multi-plug which is a very useful device with a timer which could be used to set a specific time of our desire and thus would automatically stop the current flowing to the multi plug and stop the multi-plug from working after the assigned time to it is passed. Initially we thought an analogue timer would be appropriate but considering the convenience of the users we switched to the idea of making a digital timer instead of an analogue.Furthermore, in this report you would be given a detailed idea about the background, Structure, organizational uses and applications of our project. BackgroundThis project is based on a on a multi plug which could be timed and controlled according to the consumers will. This product is designed in a way the current flowing through the appliances could be stopped according to the hours/minutes/seconds set on the time. This product Timer multi plug prevents overheating/over charging and damage of the electrical appliances. In the past there were solutions to this problem which used analogue timer which was helped to control the flow of current for a limited range of time, but the Digital timer multi-plug has no time limits. This product was designed using a programmable Arduino board, PCB, LCD screen and other electrical components. More research were done to fix all these components together to make this useful Digital Timer multi-plug. Previous workMany efforts were done, and many ideas were put forward, one of them was to use an analogue timer, and since it had a limited timing interval, this idea was rejected, and then the idea of using electronics was brought in. Afterwards, the group members had to do a lot more research on electronics since using electronics was not the initial idea. The project, as a whole includes electronics and electrical.The basic concept used in the current product is a microcontroller (Arduino) and some set of programing language which controls the microcontroller. By the help of a relay, two circuits could be controlled, one which is connected to the plug, and the other from the microcontroller, and using a program, the current to the relay could be controlled, and the second circuit could be switched on and off. Our Project could be broken down into 4 parts: the brain storming, programming, circuitry and electrical. Brain storming includes in discussing new ideas, and designing the process, including deciding the components for the digital timer multiplug. The second is the programming, this is where the programming for the microcontroller is done, and the third is the circuitry. This is where the PCB is made, and the components such as LCD display is fixed to the PCB, and the wiring is done. Lastly is the electrical, this is the power supply for the microcontroller, and the connection of relay.Power to the Digital Timer multiplug is given by connecting it to a wall socket using a powerpack. This power pack reduces the 230V to a much simpler 6-12V range which the microcontroller (Arduino) works on.The microcontroller (Arduino Uno ) features aUSBinterface, 6 analog input pins, as well as 14 digital I/O pins which allows the user to attach various extension boards. The Arduino could also be run on regular personal computers and which allows us to write programs for Arduino using CorC++. Each of the input pins and output pins are programmed for different functions. The system is programmed in a way that the current passing through the multi plug is controlled for the given period of time. This is fixed to the printed circuit board (PCB), which contains most of the circuitry.A simply illustrated diagram of the function decomposition is given below to simplify the process.

Simple Function Decomposition Diagram for Digital Timer multi-plugDigital Timer Multi-plug

Drawing designDeciding componentsBrainstormProgrammingPCBFixing componentsCircuitry Connecting relay to microcontrollerElectrical

Design Specification

Purpose of the product design specification documentThe Product Design Specification document documents and tracks the necessary information required to effectively define architecture and system design in order to give the development team guidance on architecture of the system to be developed. The Product Design Specification document is created during the Planning Phase of the project. Its intended audience is the project manager, project team, and development team. Some portions of this document such as the user interface (UI) may on occasion be shared with the client/user, and other stakeholder whose input/approval into the UI is needed.General overview and design guidelines/approachThis section describes the principles and strategies to be used as guidelines when designing and implementing the system.Assumptions / Constraints / StandardsThe basic model we assume for our analysis and design is to use a digital timer connected to a circuit board (Arduino Uno) and a relay so that we can control the current flow in the circuit using the timer and the relay switch.One of the main constraints is the programming, which we are going to design for the circuit board. It is complex and we have to bug the errors that will occur while running the code. The other constraint is the size of the final product and portability. As it is a multi-plug it will be more user-friendly if the size of the product is comparably small which the user can handle and also light weight so it is portable.

Architecture DesignThis section outlines the system and hardware architecture design of the system that is being built. Hardware ArchitectureWhen it comes to the hardware, an Arduino board is used to program the timer, and the LCD display is used to display the time the, we will set using the buttons that were fixed in the circuitry. The relay is used to cut the current flow in the specified time given by the user using the program. Software ArchitectureThe software we used to program the Arduino board uses the C+ programming compatible with the board. Using this we can program the board to set the time and make the circuit to stop the current flow at the required time. Security ArchitectureThe safety of the product is taken into account. There won't be any flaws in the circuit that would harm the user. The whole circuitry is enclosed into a casing that seals all the wires and it will be leakage proof, so no harm done for the user.

Tools & Techniques

Ishikawa Diagram

Fogetting to switch off elec. appliances

Digital Timer Multi-Plug

Convenience for elderly people Reducing energy consumption during peak hours

Objective Tree Hard

Safe

Digital Timer Multi plug Properly Working

Marketable

PortableUseful

Light Weight

MultitaskingInexpensive

Durable

Mind Map Prevents electrical appliances from over charging and overhearing

Forgetting to switch off electrical appliances when leaving home

Digital Timer Multi Plug

Convenience for elderly peopleReducing Energy Consumption during peak hours

Easy Less tiringSaves ElectricitySaves Money

Feeling lazy to walk up to the multi-plug just to switch off when youre involved in an important work

Time Saving

Alternative Analysis

Matrix1 represent yes , 0 represent NoUSER ATTRIBUTESDESIGN ALTERNATIVES

Digital Timer Multi PlugAnalogue Timer Multi-plug

Potable11

Light in Weight11

Legible Display10

Restricted time duration to set time01

Convenient manipulation to set time10

Cheap00

Detailed Design processFirstly to do any designing, a problem should be identified. In this case the problem we encountered was overcharging and overheating of electrical appliances as we forget to switch them off at the correct times. This has led to damaging of these electrical appliances and has even cause a threat to human life since some appliances tend to burst.After identifying our problem we next did a background research. This research was mainly done to get a clear understanding on what type of product we are going to make and what types of components are there in the market which can be used to make our product. This step was a very important step as it made us interfere with the market and check on what is available in the market and whether they were affordable. This even allowed us to get a rough idea on the price of our product. Also when interfering with the market we realized analogue timer multi-plugs were already there in the market which led us to use a digital timer instead of an analogue timer. Then we realized microcontroller (Arduino) coding was necessary to make a digital timer and that led us to find a way to get assistance on it as we were not very capable at it.Preliminary designDesignThe main objectives of our design is to provide a failsafe, cost efficient product that is easy to use and can be purchased at a relatively low cost. This makes it available to almost everyone in the general public, regardless of their social status. Moreover, the use of this product should not require any technical knowledge and therefore can be used by individuals of all ages. Diagram The LCD screen has 16 columns and 2 rows. This displays the time duration for which the appliance has kept on. Once it is switched off the screen displays OFF. The LCD is connected to the microcontroller (arduino). The microcontroller (arduino) is programmed to show the time allocated on the screen. A relay is connected into pin 13 of the microcontroller (arduino) where the control over the main current takes place. *********Sketch with dimension included**********

Design calculationsPerformance estimates: Weight of product 750 grams Dimensions 11.5 cm *10cm * 6cm Speed about 1 second delay Operation time 3-4 years

Testing planThe testing plan was carried out in a number of pre-planned steps. Almost all possible scenarios were covered. Essentially the testing was done in three main categories.1. Usual conditions2. Unusual Conditions3. Extreme Conditions

Usual ConditionThis includes typical, everyday situations. This is the type that the product is most likely to encounter once in use. For the product to be failsafe it should always produce the desired result in these situations. To test our product we connected it to a number of electrical appliances typically used in homes. This included 1. A charging phone2. Electric iron3. Electric heater4. Television Each of these appliances was tested separately. Once it was connected to a particular appliance. The result was noted down. It was then connected to another appliance. This process was repeated for all the appliances. The desired result was achieved. It worked with all the appliances, turning them off after a delay of about 1 second. Unusual conditionThese are situations which are not likely to happen in everyday use. These are situations in which the boundaries of the performance estimates are tested. The outcome of such situations cannot be predicted exactly.

Extreme conditionThese are situations which are not possible. The device should not respond at these situations. These circumstances would never arise in everyday life and the outcome should always be the same, the device must not work. Design implementationThe product was first implemented onto a charging phone. The device was connected onto the circuit which drew power from the main line. When time was completed the relay in our device disconnect by cutting off power for the charging phone.

Production scheduleWeek 2 Buying LCD and connect it to the arduino Run pre-stored test programs to ensure that the LCD is functioning properly.

Week 3 Connect a relay to the arduino and do a few dry runs to ensure that the voltage of the signal given out by the arduino is sufficient to operate the relay

Week 4 Program the arduino to get the necessary outputs from the LCDWeek 5 Design the PCB Give the design for production

Week 6 Connect everything onto the PCB Test it on an appliance

Week 7 Carry out the testing phaseWeek 8 Carry out the implementation phase

Cost analysisOur cost estimate and total budget Cost of the Arduino board Rs:2000 Cost of the LCD Rs.450 Power Pack Rs.380 Multi-plug- Rs.60 Cost of production of a PCB Rs.100 Plastic casing -800TOTAL: Rs. 3790

User manual

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312

5

RESET

Buttons-side view of box

Parts Identification1. Set button 2. UP of minutes,seconds and hourss3. Down of minute, seconds and Hours4. UP- increase time5. Down decrease time6. Reset- press UP- changing from hour to minute, on the right and DOWN -time decreasing button together.

Circuit Diagram

Saftey instructionsWarning!When using mains-powered appliances, basic safety precautions, including the following, should always be followed to reduce the risk of fire, elecrict shock, personal injury and meterial damage.Read all this manual carefully before using the appliace. The use of any accessory or attachment or the performance of any peration with this appliance other than those recommended in this instruction manual may present a risk of personal injury. Retain this manual for future reference.

How to use the digital timer plug1. Make sure that you havent plugged any electrical device to the appliance.2. Plug the appliance into the main power supply.3. Do the time settings as you want and plug the electrical device to the digital timer plug.4. Press the set button then it will run as the time you selected.5. After all reset the time and unplug the device and the timer plug from main supply.

After Use Switch off and remove the plug from the main supply before leaving the appliance. When not in use, the appliance should be stored in a dry place. Children should not have access to stored appliance.

Technical Data Digital timer plug (DTP)

Voltage 220-240V

Frequency50-60Hz

Rated Power1450-1750W

Specify requirementsTalking about the electronic side of our product first we decided on buying an analogue timer and directly fixing it series with a multi-plug. As this idea was simple and is readily available in the market we thought of making an analogue timer. While we were planning on making an analogue timer we got the idea of making a digital timer too. When it came to the electrical part first we dint have any problem as we just had to connect the multi-plug to an analogue timer which was readily available in the market. But with the digital timer idea we had to find a way to power up the microcontroller (arduino) board and the multi-plug, so we thought of using two separate current connections one for the microcontroller (Arduino) board and other for the multi-plug. At the same time we thought of using the same connetion and split it between the two though it was a bit inconvenient since microcontroller (Arduino) board needed only 9V whereas multi-plug needed 230V. Also to break the circuit after the assigned time is gone we thought of using two relays but at the same time we found out that there are relays of 230v to 5v and thought whether to use one relay of that instead of two.Out of the many ideas we thought of we decided to use a digital timer in our product instead of an analogue as analogue timer multi-plugs were already available in the market. Then we decided to use a power pack and get the power supply to the microcontroller (arduino) board and multi-plug from it without using to separate connections. Also we thought of using one 230v to 5v relay without using two separate relays.After finalizing our ideas we started on making a product. We started off with making the digital timer as it requires more time. First we did the circuit on a breadboard and later transferred it on to a PCB. Then we moved on to making electrical circuit by connecting components properly. Finally we made the plastic casing in such a way to fit everything into it. This how we gradually developed and made the prototype.Finally we tested our prototype. We were able to change the time in the digital timer but there was an issue with the set button and we could not the time. So we went back to redesigning and found out that there was a problem in the programming of that button and started to fix that.DiscussionAs mentioned previously due to reasons like feeling lazy to get up and go all the way up to to the multi-plug just to switch it off when your involved in some other important work, overcharging and overheating of electrical appliances simply because you couldnt switch it off at the correct time and also being able to save money spent on electricity by switching off electrical appliances during peak hours made us think of making which can give a clear solution to all these mentioned problems which are existing in our day to day lives. Also thinking in a broader way we realized this product we are going to make should also have the potential of being useful to human irrespective of age and knowledge thus we realized this product would be greatly helpful to the aged and disabled as well. So when taking all these things into consideration we came to the idea of connecting a timer in series combination to a multi-plug. For convenience of usage we decided to switch on to a digital timer where the numbers are clearly visible rather than using an analogue timer which is much harder to manipulate. By designing our product according to our idea we will get the ability to set the time to a time of our choice and let the multi-plug to work for that assigned time and cutting off the power after the time has reached. Thereby the objective of this report is to get a clear understanding on the product we made, generally from the sides of using the product properly, technical aspects of the product and the uses of the product.When we sum up and go through the report as a whole it is evident that this report provides a detailed analysis of the digital timer multi-plug we produced. Starting from the executive summary which explains overall purpose and performance of the product, we moved on to the background which emphasizes on the literature of the materials used for the project. Then we considered feasibility of the product by analyzing the cost of the components used for the product thus costing the overall cost of the product. Also a user manual which illustrates the ways to use our product in a proper manner. Finally we wrapped up the report stating recommendations and discussion.Talking about the performance of the product it is obvious that the whole purpose of this project is to design a multi-plug which can be controlled by time. The LCD screen of the multi-plug shows hours, minutes and seconds separately which provides us the ability of setting the time in hours, minutes and even in seconds. The maximum number of hours to which the multi-plug the multi-plug can be set in is 6 hours. Within this period of 6 hours the timer can be set in to any time u prefer. Furthermore, there are five buttons to control the timer of this multi-plug of which two are to increase or decrease the time, two other to change time between hours, minutes and seconds and the fifth button to set the time. Once the time of our choice has been set there will be a countdown starting from that set time till the time arrives to 0. Immediately after this the current which was passing through the multi-plug would stop serving the whole purpose of the digital timer multi-plug. Also this multi-plug can be used over and over again like all the other basic multi-plugs since adding up an additional digital timer circuit would not cause any damage to the product like overheating and also this mluti-plug will have the capability of cutting off the power immediately after the time is over and timer is turned off thus making the product more efficient and user friendly. Thus we can conclude that this product which is the digital timer multi-plug is a product with a high level of performance.Finally we thought that discussing on the things we learnt and the new things we experienced from this project is very important. Therefore first of all we should mention that none of us in our group members were very much keen on this electrical and electronic area but knowing less about the field motivated us learn more. At the start of the project we thought of buying and fixing a Analogue timer to the multi-plug but over the weeks we realized that is was costly and that is was pointless which made us move on to making a timer and by doing that we learnt a great deal about how to do microcontroller (Arduino) coding, about microcontroller (Arduino) input and output voltages and how to connect microcontroller (arduino) to the LCD screen. Basically all the knowledge we have about the Microcontroller (Arduino) was as a result of this project we carried out. The way to make a PCB was also learnt through this project since making a PCB which will fit to the plastic casing was a main requirement for us. Talking about the electrical side, we learnt a great deal about the circuit. One of the biggest problems we had was supplying power to the microcontroller (Arduino) since using 9v battery was inefficient. Thereby it made us think more and come to the idea of using a power pack with a 9v output and also using the 230v of the same power pack to the multi-plug. For this purpose we had to solder the wires which led us to improve our skills on soldering as well. We also learnt a great deal on many electrical and electronic components like how they are used and why they are used.ConclusionApart from the above mentioned subject matter learning, we were able to add more important things which would help us not only today but in the future as well. One most important fact was learning to work as a team without causing any internal problems and misunderstanding. Also we learnt to take responsibility on the areas we were assigned to do. Another important fact is, learning to handle pressure situations. We came across many situations like that throughout the time of making the project but we worked as a group and systematically sorted out all these problems. But, on the whole we would like mention that we added many things to our life and knowledge while enjoying every bit of our project that is the digital timer multi-plug which we think will be greatly useful to the people in the society.

Reference http://arduino.cc/en/Guide/HomePage http://arduino.cc/en/Tutorial/HomePage http://playground.arduino.cc/ http://en.wikipedia.org/wiki/Ishikawa_diagram http://www.wikihow.com/Make-a-Mind-Map http://www.siliconfareast.com/ishikawa.htm

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