TESTING OF POWER

ELECTRONIC COMPONENT

1.0 LEARNING OF OUTCOMES:

AT THE END OF THIS EXPERIMENT, THE STUDENTS SHOULD BE ABLE TO :->

Test the power electronic component using analogue multimeter. Find the specifications of the component from data sheets.

2.0 EQUIPMENT / APPARATUS: Analogue multimeter Component

Silicon Controlled Rectifier (SCR) 2N4444 @ 2P4M 2N5061 @ 2N5062

Triac BTA 10-600C @ BT137-800E

Light Dependence Resistor(LDR)

Light Emitting Diode (LED)

Transistor SILICON TYPE

BCY70 @ A608 C1047 @ C1359

Power and medium power transistor 2N3055 @ 2N3053

Field Effect Transistor (FET) 2N5457 @2N3819

Unijunction Transistor(UJT) 2N 4871

Programmable Unijunction Transistor(PUT) 2N6028

3.0 SAFETY AND HEALTH :

General Precautionsa. While working in Lab, be calmed and relaxed.b. The work area is kept neat and clean.c. The locations of the fire extinguishers and first aid kits in lab are

being sure.

Precautions that are taken when preparing a circuita. Only isolated power sources are used ( either isolated power

supplies or AC power through isolation power transformers).The possibility to prevent the risk of electricity shock and damaging equipment isolated oscilloscope are used.

Before powering the circuit precautions are takena. Before powering the circuit, all the connections are checked and

scoped, to avoid shorting or any ground looping that may lead to electrical shocks or damages on equipment.

b. The load connected at the output is checked.c. The wiring and the circuit connections are double checked. A

point-to-point wiring diagram is used to review those checks.

Precautions while switching ON the circuita. Low voltages and low power are applied to check proper

functionality of circuits.b. The voltages or power increased when the functionality is proven,

to check proper functioning of circuit the levels are stopped frequently or for any components that is hot or for any electrical noise that affects the circuits operation.

Precautions while switching off or shutting down the circuita. The voltage and power is reduced till it comes to zero.b. All the power supplies are switched off and the power supply

connections are removed.c. The load is let to be connected at the output for some time, so that

the capacitor and inductor is discharged completely.

Precautions while modifying the circuita. The circuit is switched off and the precautions steps are taken.b. The connections are modified according to our requirement.

4.0 THEORY :

Element 1

The component parameters are identified. Range : Parameters = Type, size, type number, rating, connections;

11 different components are identified from the candidate’s production environment are required.

Performance criteria

1) Types of component are identified.

Range: Typical types – Resistors, capacitors, diodes, integrated Circuits, thermistors, transistors, light emitting resistors,

2) Size, rating, type number, and connections are identified, as appropriate for the component.

Range :

Size – For instance values of resistance or capacitance; Type number – Of active devices such as transistors, diodes, and

integrated circuits; Rating – Where readily identifiable; Connections – Where these are important for an example

electrolyte capacitors, diodes, transistors, thyristors, transformers, coils

Element 2

Real components are matched to their representation on production line documentation or circuit diagrams.

Performance criteria

1) The production line documentation or circuit diagrams are given, the corresponding components are selected from the pool of components.

Range : Evidence of matching 11 components are selected from the candidates production environment.

5.0 PROCUDERS:

Layout as been drawn for each component and the leads labelled by referring to the component layout given.

The leads identified(cathode, anode, gate) of SCR multimeter indicated the continuity between these

terminals with the red test lead on the gate and the black test lead on the cathode.

The leads identified (terminal 1, terminal 2, gate) of TRIAC Multimeter connected as in figure below. The R x 1

range used. The measured resistance are high (greater than 1 megohm). Next, ,multimeter reconnected with reversed leads as in B. Again, the measured resistance are high.

With the multimeter leads connected as in B, momentarily the gate connected to the anode. The resistance are read low (less than 1000 ohms), even when the gate connection has been broken

The resistance of LDR measured, when in light and dark condition. In light condition

Keep the multimeter at Ohms mode. The LDR is subjected to a bright light source (day light is enough).

Now the multimeter shown a low resistance reading around 200- 500 Ohms.

Dark condition The LDR is subjected to darkness by covering it

with an opaque paper. Now the multimeter shown a high resistance

reading around 100-200K.

The leads identified(anode, cathode) of LED When the anode is connected to the red terminal while the

cathode connected to the black terminal. The result is, the LED will be working. So it helps to identify the leads.

The leads identified (emitter, collector, base) for transistor. The red meter lead connected to the base of the transistor.

The black meter lead connected to the emitter. NPN transistor reads a junction drop voltage of between 0.45v to 0.9v.

The black meter lead connected to the base of the transistor. The red meter lead connected to the emitter. PNP transistor reads a junction drop voltage of between 0.45v to 0.9v.

The leads identified (base1, base 2, emitter) for UJT The positive lead of multimeter connected to the B1

terminal and negative lead to the B2 terminal. The multimeter shown a high resistance (around 4 to 10K ). Then the positive lead connected to B2 terminal and negative lead to B1 terminal. Again the multimeter will show a high resistance (around 4 to 10K).Also both the readings will be almost same.

Negative lead of the multimeter connected to the emitter and positive lead to the B1.The multimeter shown a high resistance (around 100′s of K’s). Next the negative lead once again connected to the emitter and positive lead to B2.

Again the meter shown a high resistance. In both cases the reading are almost same. This test is almost like reverse biasing a diode.

The positive lead connected to the emitter and negative lead to B1.The multimeter shown a low resistance (around few 100 ohms). Next the positive lead once again connected to the emitter and negative lead to the B2 terminal. Again the multimeter shows a low resistance reading (around few 100 ohms).In both cases the reading will be almost same. This test is almost like forward biasing a diode.

6.0 RESULTS AND DATA

Silicon controlled rectifier (SCR)

2P4M @2N4444

CATHODE GATE

CATHODE

ANODE

GATE ANODE

2N5061

CATHODE

ANODE GATE

TRIAC

BTA10- 600 C @ BT137- 800E.

TERMINAL (-)

BASE

TERMINAL (+)

LIGHT DEPENDENCE RESISTOR (LDR)

BRIGHT - 300Ω

DARK - 100k Ω

LIGHT EMITTING DIODE (LED)

CATHODE (-)

ANODE (+)

TRANSISTOR

SILICON TYPE A608

COLLECTOR

BASE

EMITTER

SILICON TYPE C1359

COLLECTOR

BASE

EMITTER

C1047

COLLECTOR

BASE

EMITTER

POWER AND MEDIUM POWER TRANSISTOR 2N3053

EMITTER

COLLECTOR

BASE

UNIJUNCTION TRANSISTOR 2N4871

BASE 1

EMITTER

BASE 2

PROGRAMMABLE UNIJUNCTION TRANSISTOR (PUT) 2N608

CATHODE

ANODE

GATE

7.0 DISCUSSION

It is significant to test a component before applying it to an electronic circuit. The entire electronic component have different criteria’s and it is important to test it before using this is mainly because to avoid electrical shock, damage to the electronic component. Other than that by testing the component we also can avoid short circuit. Moreover, the of knowing the specification of the component is to build a good connection without any faulty in the circuit. Some component is usually expensive. So it is important to test that component properly. Testing an electronic component is a part of the safety precautions to avoid electrical shocks and damaging the equipment.

8.0 CONCLUSION

The specifications of the electronic component are determined through this experiment. All the components are tested using analogue as precautionary steps. Data sheet is used to fulfil this experiment. This experiment is conducted to avoid any accidents such as short circuit and electrical shocks and damages on component. The observation is accepted.