INVISIBLE BROKEN WIRE DETECTOR

1. INVISIBLE BROKEN WIRE DETECTOR PRESENTED BY: EJAZ AHMED CS12B1023 VINAY VAMSHI REDDY R EE12B1040 SAI TEJA EE12B1031

2. WHY WE NEED IT?? • Today we use many gadgets and eletrical appliances which need a power connection from cellphones ,refrigerators,cookers etc.. • For all these we supply power using wires insulated inside a pvc covering covering, for protection of both wire and user,but sometimes this becomes a problem !! • Over a period of time due to stress and other factors the wire inside the insulation gets broken and stops functioning • It is difficult to detect the exact location of this fracture and many a time the component needs to be replaced • This is Why we need the “INVISIBLE BROKEN WIRE DETECTOR” • It locates the breakage point very accurately and the insulation can be removed at that point and the wire can be repaired saving us a lot of time ,money and material resources

3. How we do it? • Our basic aim is to build a circuit to locate the broken point without removing the pvc cover • To detect the exact location of breakage inside the pvc cover we employ our circuit with a hex inverter CMOS which uses its actions to control an oscillator which in return detects the presence of an ac current and shows the location till which the current is passing . • It is built using hex inverter CMOS CD4069.Gates N3 and N4 are used as a pulse generator that oscillates at around 1000 Hz in audio range. The frequency is determined by timing components comprising resistors R3 and R4 an capacitor C1 • Gates N1 and N2 are used to sense the presence of 230 V AC field around the live wire and buffer weak ac voltage picked up by test probe.

5. The voltage of output pin 10 or gate N2 can enable or inhibit the oscillator circuit.Whenyhe test probe is away from high voltage ac field output pin 10 of gate N2 remains low.As a result diode D3 conducts and inhibits the oscillator cirircuit from oscillating. • Simultaneously ,the output of gate N3 at pin 6 goes low to cut of transistor T1.As a result LED 1 goes off.when the test probe is moves to 230 V AC,50 Hz mains live wire,during every positive half cycle,outpin of 10 goes high.Thus during every positive half cycle of mains frequency N2 goeeshigh,and oscillator circuit is allowed to oscillate at around 1000kHz making LED 1 to blink. • The voltage of output pin 10 or gate N2 can enable or inhibit the oscillator circuit.Whenyhe test probe is away from high voltage ac field output pin 10 of gate N2 remains low.As a result diode D3 conducts and inhibits the oscillator cirircuit from oscillating. • Simultaneously ,the output of gate N3 at pin 6 goes low to cut of transistor T1.As a result LED 1 goes off.when the test probe is moves to 230 V AC,50 Hz mains live wire,during every positive half cycle,outpin of 10 goes high.Thus during every positive half cycle of mains frequency N2 goeeshigh,and oscillator circuit is allowed to oscillate at around 1000kHz making LED 1 to blink.

6. How to Use? • To detect the breakage point, turn on switch S1 and slowly move the test probe closer to faulty wire,beginning with the input point of live wire and proceeding towards other end • LED1 starts glowing during presence of af ac voltage in faulty wire,when the breakage point is reached LED1 stops due to non availability of AC field.That point is the location of breakage

7. Components Used • Contains 6 inverter Circuits made using complimentary MOS • Wide supply Voltage range :3 V – 15V • High Noise Immunity:.45VDD type CMOS HEX INVERTER CD 4069 IN4148 High speed switching diodes High switching speed :max. 4 ns General application Continuous reverse voltage :max. 100V Repetetive peak reverse voltage: max.100V Repetetive peak forward current: Max. 450 mA • Low power TTL compatibility: Fan out of driving 74L • Operating Temperature Range(TA): -55C to +125C

8. BC547 Transistor • A component wirh three terminals B(Base), C(collector) , E(Emitter). • A Drawing of a BC547C transistor Resistors Used In the Circuit • 47 Ohm Resistor • 1M Ohm Resistor • 560 Ohm Resistor • 220 Ohm REsistor

9. RESULTS • Thus the circuit was made successfully which can easilydetect broken point in the wire inside the PVC cover withour disturbing it • The whole circuit can be accomodated in a small pvc pipe and used as a handy broken wire detector.This will make the circuit more compact and easy to handle.The handy broken wire detector can be taken anywhere and every where and becomes less prone to damage. CONCLUSIONS • The circuit made is cheap and best.It would not only be able to Reduce wastage of time but also resources • Thus using just a hex inverter and few resistors we are able to construct a device which can easily detect a faulty broken wire and thus save the extra cost of user which is incurred on replacing the faulty wire and not repairing it which is difficult.

10. Improvements • We can use an inverter in between the LED and the oscillator which will then turn on the LED only when broken point is detected and keeping it off when the wire is not broken.By making this change we can make our detector more user friendly and also consume less power • We can also use a beeper to sound alarm when breakage is detected