We come across many railway accidents occurring at unmanned railway crossings due to carelessness in manual operations or lack of workers Railroad related accidents are more dangerous than other transportation accidents in terms of severity and death rate etc. We, in this project has come up with a solution for the same.

1. Warning System for Unmanned Railway
Crossings
Presented By
Vikrant
Vipin
Vishesh
Yogesh
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Project Guide
Mrs. Jasmine Kaur Boparai
Assistant Professor
ECE Department

2. Project Selection
• Railway safety is a crucial aspect of rail operation over the world.
Railways being the cheapest mode of transportation are preferred over
all the other means.
• We come across many railway accidents occurring at unmanned railway
crossings due to carelessness in manual operations or lack of workers
• Railroad related accidents are more dangerous than other transportation
accidents in terms of severity and death rate etc.
• We, in this project has come up with a solution for the same.

3. Basic Idea
• Present project is designed using reed relay as a sensor to avoid railway
accidents happening at unattended railway gates, if implemented in spirit.
• This project utilizes two IC namely NE555 timer and CD7404.
• Reed relay is fixed at upside (from where the train comes) at a level
higher than a human being in exact alignment. It gives warning to people
by glowing red or green light using LEDs or Bulbs at crossings.
• Indian Railway also uses some warning signs at some distances near railway
crossings.

4. Components Used
• 555 Timer IC
• IC74LS04
• LED
• Resistor
• Capacitor
• Reed Switch

5. General Description
• This crossing light indicator circuit is based on two IC namely NE555
timer and CD7404 with few more discrete components.
• In this we are using reed relay as a sensor which comes in two varieties that
is normally open and normally close.
• In relay, due to of electromagnet field nearby its coil energises.
• In normally open condition reed switch is open and when magnet is bring
close to it, it become close.
• And in normally close condition it will remain closed in normal state and
when magnet is bring near the reed switch it become open.
• In this circuit we are using normally open reed switch. For this circuit to
work trains must have magnets attach to it.

6. Circuit

7. IC555
• 555 is a very commonly used IC for generating
accurate timing pulses.
• It is an 8pin timer IC and has mainly two modes
of operation: monostable and astable.
• In monostable mode time delay of the pulses
can be precisely controlled by an external
resistor and a capacitor whereas in astable
mode the frequency & duty cycle are controlled
by two external resistors and a capacitor.
• 555 is very commonly used for generating time
delays and pulses.

8. Modes of Operation of 555
Timer
• Astable - producing a square wave
• Monostable - producing a single pulse when triggered
• Bistable - a simple memory which can be set and reset
• Buffer - an inverting buffer (Schmitt trigger)

9. Features and Applications
Features
• High Current Drive Capability
(200mA)
• Adjustable Duty Cycle
• Temperature Stability of
0.005% /°C
• Timing From µSec to Hours
• Turn off Time Less Than 2µSec
Applications
• Precision Timing
• Pulse Generation
• Time Delay Generation
• Sequential Timing

10. IC 74LS04
• 7404 is a NOT gate IC.
• It consists of six inverters which
perform logical invert action.
• The output of an inverter is the
complement of its input logic state, i.e.,
when input is high its output is low and
vice versa.

11. Pin Description
Pin No. Function Name
1 Input/output of 1st inverter Input 1
2 Output 1
3 Input/output of 2nd inverter Input 2
4 Output 2
5 Input/output of 3rd inverter Input 3
6 Output 3
7 Ground (0v) Ground
8 Input/output of 4th inverter Output 4
9 Input 4
10 Input/output of 5th inverter Output 5
11 Input 5
12 Input/output of 6th inverter Output 6
13 Input 6
14 Supply Voltage 5V Vcc

12. Reed Relay
• A reed relay, which uses an electromagnet to control one or several reed
switches, has contacts which are mounted on magnetic reeds that are
scaled into a long narrow glass tube.
• An actuating coil is wound on an auxiliary ferrite-core structure or
around the glass tube in order to provide the magnetic field that is
required for the relay to operate.
Some of the applications of Reed Relays are:
•Broadcasting and video equipment •Process Control
•Security •Automatic Test and Measurement
Equipment
•Mobile phone base stations
•Instrumentation •Industrial

13. Circuit Diagram
1
3
2
4
6
7
8
+5V
IC
555
RED
LED
Green
LED
1 2
14
7
Reed
Relay
R1
4K
R2
4K
R3
1K
R4
1K
IC2
7404

14. Working
• In this circuit NE555 is configured in monostable mode.
• In this mode time delay of the pulses can be precisely controlled by an
external resistor R1 and a capacitor C1. And 7404 is an inverter IC which
contain 6 individual NOT Gate on a single IC.
• Its outputs go low when input is high. And its output becomes high when
input is low that's why it is known as inverter IC.
• Now when train comes reed switch which is normally open state becomes
close because of the magnet attach on the train which will trigger the pin 2
of IC1 and output pin 3 of IC1 goes high and RED LED becomes on to
indicate that train is going to come. So that people may not crosses the
railway line.

15. • As soon as train passes away reed
switch again come to its normally
open condition as there is no more
magnetic effect and pin 2 of IC1
goes low. Which will also make pin 3
of IC1 also low which in turn
provided to IC2 which is a inverter
IC and its output pin 2 become high
and GREEN LED will glow to
indicate that you can cross the
railway line.
1
3
2
4
6
7
8
+5V
IC
555
RED
LED
Green
LED
1 2
14
7
Reed
Relay
R1
4K
R2
4K
R3
R1
IC2
7404

16. Conclusion
• A new approach for improving safety at LCs has been suggested.
• This approach should be able to bring down the rising trend in accidents at
unmanned LCs.’
• This project uses the present infrastructure of railways e.g. present
signaling method and meets all the requirements to have an automatic
controlling of the railway traffic.
• It provides the supervision and control system provide the mean for real
time inspection review and data collection for the purpose of maintenance
on the movable and fixed facilities for the guarantee of operation safety
and maintenance efficiency as well as the safety appraisal decision-making
system based on the share of safety data.

17. Future Scope
• This project is developed in order to help the INDIAN RAILWAYS in making its
present working system a better one, by eliminating some of the loopholes existing in
it.
• Based on the responses and reports obtained as a result of the significant
development in the working system of INDIAN RAILWAYS, this project can be
further extended to meet the demands according to situation.
• This can be further implemented to have control room to regulate the working of the
system. Thus becomes the user friendliness.
• This circuit can be expanded and used in a station with any number of platforms as
per the usage.
• Additional modules can be added without affecting the remaining modules. This
allows the flexibility and easy maintenance of the developed system.

18. References
• Demirdjioghlou, S. and M. Copeland, Force measurements on magnetic reeds, IEEE
Transactions on Magnetics, Jun 1968, Volume 4, Issue 2, pp. 179- 183. ISSN 0018-
9464
• Gurevich Vladimir, “Electronic Devices on Discrete Components for Industrial and
Power Application”, pp. 418, CRC Press, London - New York, 2008
• Hinohara, K., T. Kobayashi, and C. Kawakita, Magnetic and mechanical design of
ultraminiature reed switches. IEEE Transactions on Components, Hybrids, and
Manufacturing Technology, Apr 1992, Volume 15, Issue 2, pp 172-176. ISSN 0148-
6411 DOI 10.1109/33.142891
• Miedzinski, B., and M. Kristiansen, Investigations of Reed Switch Dynamics and
Discharge Phenomena When Switching Intermediate and Heavy Loads. IEEE
Transactions on Components, Hybrids, and Manufacturing Technology, Jun 1982,
Volume 5, Issue 2, pp. 231- 237. ISSN 0148-6411
• Paul P., “Sensors for Mechatronics”, pp. 137-138, Elsevier, 32 Jamestown Road,
London NW
• Pessen David W., “Circuit Design and Components”, pp. 46-55, Industrial Automation,
Wiley-Interscience Publication, 1989

19. References
• Pinnel, M., Magnetic materials for dry reed contacts. IEEE Transactions on
Magnetics, Nov 1976, Volume 12, Issue 6, pp. 789- 794. ISSN 0018-9464
• Reed Switch, from website, http://en.wikipedia.org/wiki/Reed_switch
• Rudolf F. Graf, “reed relay” Dictionary of Electronics; Radio Shack, 1974-75.
Fort Worth, Texas. “Electric Relays: Principles and Applications”, pp. 671,
Vladimir Gurevich, CRC Press, London - New York, 2005
• San Franciscos “Advanced automatic warning signal system” in Proc. CERIE 2010,
paper C, pp. 297, 2010
• Sethia Anjali, Crossing Light Indicator, from website,
http://www.engineersgarage.com/electronic-circuits/crossing-light-indicator