Design and Implementation of an Automatic Security Lighting for ATBU, Yelwa Campus

Design and Implementation of an Automatic Security Lighting for ATBU, Yelwa Campus

Chior David #1, Ifeora Henry #2 and Lisiyas Alfred #3.

#1 Department of Electrical & Electronics Engineering, Abubakar Tafawa Balewa University, Bauchi.

#2 Department of Systems Engineering, University of Lagos, Lagos.

#3 Department of Electrical & Electronics Engineering, Bayero University Kano, Kano.

 

Abstract— This paper has covered the design of an automatic security lighting system for ATBU, Yelwa Campus. An electronic control, based on a Light Dependent Resistor (LDR) is built, which provides automatic switch on and switch off of the system at dusk and dawn respectively. A delay is incorporated so that the circuit does not responds to small changes in illumination and any momentary brightness the transducers may sense and power requirements for the system is evaluated.

Keywords—LDR, Delay, Transducer and Electronic Circuit.

 

I. INTRODUCTION                                                                                                  

 

Security lights are the major requirements in today’s life of transportation for safety purposes and avoiding accidents during night [1]. Despite that in today’s busy life no one bothers to switch it off and on when not required. The project introduced here gives solution to this by eliminating manpower and reducing powerconsumption [2].

This requires three basic components i.e. LDR, Sensors and Operational Amplifier. During daytime there is no requirement for security lights so the LDR keeps the security light off until the light level is low or the frequency of light is low the resistance of the LDR is high. This prevents current from flowing to the base of the transistors, thus the security lights do not glow. As soon as the light level goes high, photons absorbed by the semiconductor give bound electrons enough energy to jump into the conduction band. The resulting free electrons (and their hole partners) conduct electricity, thereby lowering resistance. Now the circuitry goes in on condition and the block diagram represented here startsworking.

The automatic security lighting system for ATBU, Yelwa Campus, would not only help to reduce night time accidents on campus, or serve as deterrent to crime at night, but will also make the surrounding to beattractive.

Above all, it would provide visibility aid for the greater population of students and staff at night. The technique of street lighting is that of seeing by silhouette or reverse contrast.

 

II. LITERATURESURVEY

A. Light dependent Resistor

A Light Dependent Resistor (LDR) or a photo resistor is a device whose resistivity is a function of the incident electromagnetic radiation [3]. Hence, they are light sensitive devices. They are also called as photo conductors, photo conductive cells or simply photocells. A light dependent resistor works on the principle of photo conductivity. When light falls i.e. when the photons fall on the device, the electrons in the valence band of the semiconductor material are excited to the conduction band. These photons in the incident light should have energy greater than the band gap of the semiconductor material to make the electrons jump from the valence band to the conduction band [4] [5]. Hence when light having enough energy strikes on the device, more and more electrons are excited to the conduction band which results in large number of charge carriers. The result of this process is more and more current starts flowing through the device when the circuit is closed and hence it is said that the resistance of the device has been decreased.

Figure1: Light Dependent Resistor

B. Delay

In electronics, digital circuits and digital electronics, the propagation delay, or gate delay, is the length of time which starts when the input to a logic gate becomes stable and valid to change, to the time that the output of that logic gate is stable and valid to change [4]. Propagation delay increases with operating temperature, as resistance of conductive materials tends to increase with temperature. Marginal increases in supply voltage can increasepropagation delay since the upper switching threshold voltage, VIH (often expressed as a percentage of the high-voltage supply rail), naturally increases proportionately. Increases in output load capacitance, often from placing increased fan-out loads on a wire, will also increase propagation delay

C. Transducer

 A transducer is a device that converts energy from one form to another [4]. Usually a transducer converts a signal in one form of energy to a signal in another. Light transducers are used in those places where it is required to activate, for example, an artificial light source or when daylight intensity decreases and a source of light is necessary. Light transducers capture light intensity and convert it into an electrical signal. They use a light beam and convert it into a usable electric signal. This allows for example a production room to maintain the same brightness

D. Relevant Researches

N. Nithya and M. Hemalatha from School of Computing, SASTRA University, Thanjavur, Tamil Nadu, India, designed and implemented a GSM Based Cost Effective Security Lighting Application. One of the major issues in India was electricity problem, a lot of electricity wastage happen in India and this must be avoided. This project includes the explanation about how to save the electricity usage in term of overload issue, power cut off and security light. The transmission of data to the server, disconnection of power and complaints was done by the GSM. In the project, there were seven devices, which include PIC16F877A, LCD, current transformer, GSM, RTC and keypad. PIC 16F877A was selected as microcontroller in this project because it supports 40-pin 8-Bit CMOS FLASH and high-performance RISC. Due to load balancing problem, current transformer uses to send the load details continuously to controller [5]. Electrical energy can be transfer from one circuit to another by using the inductive couple conductor in transformer. The present value that sends to the microcontroller will compare with the set up predefined value. The GSM sends the SMS when the present value higher than the predefined value.

Zhataf k. Albert from University of Sheffield, United Kingdom, in his project designed and implemented a Remote Security Lighting Monitoring and Control System. Currently, street lights are controlled by photocells. These have only one function, which is switching lights on and off according to factory-fixed, light-level thresholds. Telensa’s proposed system operates by replacing the traditional photocell with an ‘outstation’. This performs the lamp switching and monitoring functions. It also contains a small radio, which communicates back to the base station or ‘hub’. A large deployment would have a number of hubs, which themselves would be connected to central system computer and database [6].

 

III.METHODOLOGY

Generally, our research can be divided into these stages as depicted in Figure 2, and they will be explained in detail in the following subsections

Figure 2: Block diagram of the automatic security lighting system

 

 

When the power supply is switched ON, the comparator compares the reference voltage with the voltage of the sensor unit as show in figure 2. The output of the comparator is delayed for few seconds in case of abnormal situation before the switching unit switches on the LEDs.

A. Power Supply UnitDesign

The operating d.c voltage required to power the system is 9 Volts and the regulated power supply is therefore designed to meet this requirement.

I. TransformerSection

A 240V/15V, 500mA transformer was used.

 

 

Figure 3: Power supply unit

 

From figure 3, during the positive half cycle, diode D2 and D4 are forward biased, hence they both conduct while during the negative half cycle, diode D1and D3 are reversed biased and both diode acts as reverse blocking diodes. Below is how the output rectified voltage is obtained

 

B. Sensor Unit

Light Dependent Resistor(LDR) being a photoconductive cell has the following resistances;

 500kΩ- 10MΩ for darkness and 1kΩ-100Ω for bright light.

The LDR is connected in series with a 100kΩ (resistance of bright light) variable resistor and 1kΩ resistor. This is placed in order to obtain a voltage drop across the LDR in such a manner that, the obtained voltage is below and above the reference voltage for comperes by the comparator.

When the intensity of light is low(dark), the resistance of the LDR can increase to about 1MΩ depending on the intensity of the darkness.

Assuming a resistance of 10MΩ for the LDR and adjusting the variable resistor to about 50KΩ

Voltage drop on the variable resistor,

Where; RLDR = Resistance of the LDR

RV = Resistance of the variable resistor

RK = Constant Resistor                                                                                                              

VCC = System Voltage

      V1 =   X VCC  =  X 9 = 8.95V

 

Assuming a resistance of 500KΩ for the LDR and adjusting the variable resistor to about 50KΩ.

V2 =    × 9 =8.17V

When the intensity of the light is high, the resistance of the LDR drops to about 1000Ω-50kΩ in bright sunlight.

Voltage drop on the variable resistor

V3 =  =

 

Assuming a resistance of 20kΩ, voltage drop on the resistor

V4 =  =

 

The variable resistor is therefore adjusted to 50kΩ to suit the design

C. Reference Input

Two resistors of equal value are connected in series. For this purpose, two – 10KΩ resistors

are being used.

V ref= =

 

D. Comparator UnitDesign

A UA741 operational amplifier is used to serve this purpose.

Absolute maximum ratings are Vcc - supply voltage = ± 22V, Vi- input voltage = ±15V

 

E. Delay UnitDesign

Many factors were put into considerations ranging from lightning to light from moving vehicles among many others. Based on these factors, the time delay of 45seconds was set using a RC circuit., the delay time is obtained from the delay unit and switching unit as: T = O.632RC; setting C = 1000µF, R = 71.2KΩ

T=O.632ecs

 

F. Switching Unit Design

A TIP31C transistor is used which has the following specifications;

Maximum collector to emitter voltage (VCEO) = 100v

Maximum collector to base voltage (VCB) =100V

Maximum emitter to base voltage (VBEO) = 5.0V

Maximum collector current, Ic =5A

Maximum forward current gain, hfe= 50

The specifications of the relay are;

Excitation voltage =9V

Coil resistance=300Ω

Maximum Coil current= 5A

When the transistor is used as a switch, it operates between the cut-off and saturation region.

I.                    At cut-off Region;

 

Vin≤VBE and IB = IC =IE =0A

Hence no current flows through the transistor.

 

II.                 At Saturation;

 

Vin ≥ VBE(ON)

Ic(sat)  =βIB(sat)  where β = hfe = 50

 

At edge of saturation(eos)

 

Ic(eos) =

VCE(sat)  = 1.2 V, Rc = 300Ω

IC(eos)  =  = 26mA

 

IB(eos) =  = 0.52mA

To get the value of resistor to bias the base of the transistor

Vin = IBRB+VBE

When the comparator output swings high, the output voltage is 9V

 

9= (0.52 x 10-3)RB + 5

RB = 7.69KΩ

A 1 MΩ variable resistor is provided for that purpose

A diode (IN4004) is connected across the relay coil to prevent reversal of current.

 

G. Lighting Unit

In this unit, Light Emitting Diodes(LEDs) are used to serve as lamps.

Max. current rating of LED is 420mA

Since relay has a maximum coil current of 5A, possible number of LEDs the relay can withstand will be;

5A/0.42A= 11.9

Therefore, a maximum of 11 LEDs can be used.

A survey was carried out round the campus, it was discovered that there are five distribution transformers positioned at different locations. It was decided security lights should be powered from the nearest distribution transformer around them.

This decision is taken so that power loss due to long run of cables will be reduced and power consumed by security lighting system is shared amongst the five transformers, for these reasons, the campus is divided into five zones.

Each zone is to be served from a separate transformer.

Figure 4: Circuit diagram of an automatic security lighting system

 

IV RESULTS AND DISCUSSION

 

I.TEST OF POWERSUPPLY

 

The power supply unit of 9V was tested for voltage output under no- load and full load condition.

At no- load, the voltage of 9V supply was measured to be 8.9V. At full load, it was measured to be 8.7 V

VR  = X 100%                                                                                                                                                      … (6)

VNL = No load voltage VFL=Full load voltage

VR  =  x 100 =2.2%

 

 

 

 

 

Figure 5: Front view of the soldered circuit

 

 

 

 

Table 1: Current, voltage, Power and Cable sizes of ZONE I

 

No of Lamps

Current in Zone I(A)

Fuse Rating(A)

Distance(m)

Voltage Drop(V)

Cable Sizes

23

4.65

13

760

21.5

mm2

mA

V/A

 

Total Power consumed in Zone I (W)

40

10

24

Contactor rating

                                        2160

240,30A(DC operated)

 

 

 

Table 2: Current, voltage, Power and Cable sizes of ZONE II

No of Lamps

Current in Zone II(A)

Fuse Rating(A)

Distance(m)

Voltage Drop(V)

Cable Sizes

24

4.85

13

605

19.45

mm2

mA

V/A

 

Total Power consumed in Zone I (W)

40

10

24

Contactor rating

2210

240,30A(DC operated)

 

 

Table 3: Current, voltage, Power and Cable sizes of ZONE III

No of Lamps

Current in Zone I(A)

Fuse Rating(A)

Distance(m)

Voltage Drop(V)

Cable Sizes

29

4.85

30

970

24.05

mm2

mA

V/A

 

Total Power consumed in Zone I (W)

40

10

24

Contactor rating

                                 2680

240,60A(DC operated)

 

 

 

Table 4: Current, voltage, Power and Cable sizes of ZONE IV

No of Lamps

Current in Zone I(A)

Fuse Rating(A)

Distance(m)

Voltage Drop(V)

Cable Sizes

28

5.74

30

885

18.6

mm2

mA

V/A

 

Total Power consumed in Zone I (W)

25

15

53

Contactor rating

                              2560

240,60A(DC operated)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Table 5: Current, voltage, Power and Cable sizes of ZONE V

 

No of Lamps

Current in Zone I(A)

Fuse Rating(A)

Distance(m)

Voltage Drop(V)

Cable Sizes

30

3.97

13

855

10.15

mm2

mA

V/A

 

Total Power consumed in Zone I (W)

16

5.2

47

Contactor rating

                     2730                                   2730

240,60A(DC operated)

 

 

V.CONCLUSION AND RECOMMENDATION.

I.CONCLUSION

In summary the automatic security lighting system for ATBU, Yelwa Campus based on a Light Dependent Resistor (LDR) provides automatic switch on and switch off of the system at dusk and dawn respectively. Also from the results obtained, the circuit does not respond to small changes in illumination and any momentary brightness the transducers may sense due to the delay incorporated in the circuit and minimal power losses wasensured.

In conclusion, the project design and implementation of an Automatic Security Lighting System for ATBU, Yelwa Campus switches on and off when there is light and darkness respectively only, thereby ensuring minimal power wastage.

Figure 6:Model of the automatic security lighting system for ATBU, Bauchi Yelwa Campus

 

 

 

 

II.RECOMMENDATION

The project has been built as it was intended but there is still room for improvement. Possible areas of improvement could be, using a 555 timer for the delay unit. Also in the choice of the automatic control circuit, remote infrared control switches may be used, operated by the security officers instead of the light depended switches. A microcontroller can equally be used in place of a light dependent resistor.

 

ACKNOWLEDGMENT

The first author, Chior David, would like to acknowledge the good support given by Ifeora Henry and Lisiyas Alfred from Department of Systems Engineering University of Lagos and Department of Electrical Engineering Bayero University Kano respectively.

 

REFERENCES

 

[1]

S. A. ADEIZA, "Design And Construction Of An Automatic Security Lights Control System With Open Circuit Detector," http://dspace.futminna.edu.ng/jspui/bitstream/1/4040/1/Pages%20from%20OCRELT2723.pdf, Minna, 2008.

[2]

Gouthami. C , Santosh. C , A. Pavan Kumar , Karthik. A, Ramya.K.R, "Design and Implementation of Automatic Street Light Control System using Light Dependent Resistor," International Journal of Engineering Trends and Technology (IJETT), p. 465, 2016.

[3]

R. Santhosh Kumar, Dr. Prabu, S. Vijaya Rani and P. Venkatesh, "Design and Implementation of an Automatic Solar Panel Based Led Street Lighting System Using Zigbee and Sensors," Middle-East Journal of Scientific Research, vol. 23, no. 4, p. 573, 2015.

[4]

Sharath Patil G., Rudresh S.M, Kallendrachari.K ,M Kiran Kumar Vani H.V, "Design and Implementation of Automatic Street Light Control Using Sensors and Solar Panel," International Journal of Engineering Research and Applications, vol. 5, no. 2248-9622, p. 97, 2015.

[5]

"Light Dependent Resistor: LDR and working Principle," 25 January 2019. [Online]. Available: https://www.electrical4u.com/light-dependent-resistor-ldr-working-principle-of-ldr/.

[6]

FARZANA YASMIN, MD. AL MUHAIMIN SARKAR, "AUTOMATIC LIGHT CONTROL BY USING MICROCONTROLLER BASED LDR," http://www.academia.edu, 2014.

[7]

N. Nithya and M. Hemalatha , "GSM Based Cost Effective Security Lighting Application," SASTRA University, India, 2008.

[8]

Z. K. Albert, "Remote Security Lighting Monitoring and Control System," University of Shelfied, United Kingdom, 2006.

 

ABOUT THE AUTHORS

Chior, David Terlumun is from Benue State, Nigeria. He completed an award undergraduate degree of “B.Eng.(Hons) Electrical and Electronics Engineering” in 2015 from Abubakar Tafawa Balewa University, Bauchi, Nigeria. His research interests include distributed generation, and smart grid network

Ifeora Henry received his B.Eng.(Hons) in Electrical and Electronic Engineering in 2015 from the Abubakar Tafawa Balewa University, Bauchi, Nigeria. and his M.Sc. in 2019 from the University of Lagos in Systems Engineering. He is currently a Trainee Engineer with Ikeja Electric Plc. His research interests include power, software development and modelling & simulation.

Lisiyas Alfred is a Systems Operator at Transmission Company of Nigeria, 132/33KV Substation, Mayo, Belwa, Adamawa State, Nigeria. He bags his first degree in Electrical & Electronics Engineering (Electronics Options) at Abubakar Tafawa Balewa University Bauchi in 2015.He is currently a M.Sc. Researcher at Bayero University Kano, Kano, Nigeria with research interest in microcontroller programming and telecommunications