TENS 2146 Electric Devices and Measurements Lab several Current and Voltage This kind of report was prepared by: L. Wall Fall season 2009 Prof. R.
Alba-Flores Team Members: J. White, T. Wall Executed on: September 17, 2009 Submitted about: September 24, 2009 Abstract: In this laboratory students experimented with light emitting diodes. Students built a simple circuit with two LED’s and resistors in parallel. The effects showed the voltage is definitely the same in parallel. The things that were in series got the same current.
The outcomes also revealed that the current from each branch could be summed approximately equal the total current through the source. The experiment as well helped trainees to see the voltage drop through the diode was almost a similar each time. This kind of lab demonstrated the effects of current and volts in a seite an seite circuit. This experiment likewise showed the way the brightness was effected by simply changing the voltage. Products and components: ¢ Multimeter ¢ Power ¢ Hooking up wires ¢ A loaf of bread board ¢ A 330 ohm resistor ¢ A l k ohm resistor ¢ 2 Red LED’s Theory: A light-emitting diode (LED), is usually an electronic source of light.
The 1st LED was built in the 1925 simply by Oleg Vladimirovich Losev, a radio tech who pointed out that diodes found in radio receivers emitted mild when current was that passes them. The LED was introduced as being a practical electric component in 1962. Every early gadgets emitted low-intensity red light, but modern LEDs can be found across the obvious, ultraviolet and infra reddish wavelengths, with very high lighting.  Figure 1 . Basics Physics basic principle of an LED LED’s are semiconductors. They will only work if perhaps placed in the correct direction.
Placing the LED inside the improper course could potentially destruction it. The LED is also damaged if this was not mounted with the use of a resistor. They can not be connected straight to a electric power source. The anode is a positive end and the cathode is the adverse end. LEDs are helpful because they just do not require very much voltage to be illuminated. The LEDs are good for conservation of energy. When we subtract the LED voltage through the supply ac electricity it gives you the voltage that must be dropped by dropping resistor. A decline in voltage can lead to a decrease of the brightness of the light bulb .
Figure a couple of shows the electrical symbol and the genuine shape of a great LED. Determine 2 . Power symbol as well as the actual form of an LED Ohms legislation is used to be able to calculate the latest and the resistance across each one of the elements inside the circuit. To assess the signal It must be known that the volt quality is the same in a seite an seite circuit. The existing is the same in a series. The current through each branch can be added up in in an attempt to determine the present from the origin. From Kirchhoff’s loop law it can be identified that the quantity of all of the volt quality drops around a closed loop need to sum to equal absolutely no.
The objective of this lab was for trainees to use all their knowledge of items such as LED’s, series and parallel outlet configurations, Kirchhoff’s laws, and Ohm’s rules in order to effectively analyze and solve difficulties with given routine.  Lumination Emitting Diodes, http://en. wikipedia. org/wiki/Light-emitting_diode Method: First thing we all did inside the lab was going to create the circuit. We all created the signal by using resistors with values of Rl = 330 ohms and R2 sama dengan l k ohms and also by placing the LEDs after the Resistors so there would be not any damage completed the LEDs.
This s i9000 shown in figure three or more. The voltage supply was set at 8 V and then we tested the values intended for voltage and current. To measure voltage the inmiscuirse has to be in Parallel with all the circuit. Current is measured by putting your Multimeter in series together with the circuit. In preparation intended for the research we developed the routine (shown below) using Multisim. We used simulations to get all the measurements and used Ohm’s Law (E=I*R) to solve for the rest. In the laboratory we create the same signal by connecting the resistors and the LED’s in a parallel circuit to the power supply.
Almost all of the connections were done making use of the breadboard. We measured current by putting your Multimeter in series with all the entire routine. We established the Multimeter to evaluate amperes and turned the strength on. We all continued this kind of using the almost 8, 6, 4, and a couple of volts (adjusted on the electricity supply) whilst noting the brightness in the LED’s and writing down the value given by the Multimeter. All of us then connected the Multimeter in seite an seite with each resistor and LED’s to measure volt quality. We arranged the multimeter to volts then cycled through eight, 6, 5, and two volts on the power supply and noted the reading for every connection.
All of us then employed Ohm’s Rules to calculate the current through as well as the resistance for each LED. We as well calculated the whole current to see if it coordinated what we measured. Figure 3 Circuit integrated the lab Test Calculations: To calculate the latest through every single resistor-LED part, Ohm’s Law (V sama dengan IR) utilized. In this Lab the formula used was I Rl = VRl / R 1 Case: IRl = VRl / R1 = 5. almost 8 V / 3300? = 0. 0176 A To calculate the overall resistance of each LED, Ohm’s Law utilized. In this research laboratory the formula RLED sama dengan V LED / ILED was used. Case in point:
RLED = V LED / ILED = 2 . 18 v /0. 0175 mA sama dengan 124. 57? To estimate the total current that the power supply was rendering to the two branches, the equation FOR INSTANCE = IRl + IR2 was used. With this lab the equation that was given to use was ILEDl = IRl. Example: I LEDl + I LED2 = FOR EXAMPLE. 0175 &. 0058 sama dengan. 0233 Ruse Results: Multisim was used to perform the simulations. Figures 5, 5, six and 7 shown the results obtained in the simulations. Table 1 summarizes these kinds of results. Determine 4. Electrical power supply= almost eight volts: Concentration measured throughout R1 and R2 and currents through each LED
Figure 5. Power supply= 6 v: Voltages assessed across R1 and R2 and currents through each LED Number 6. Power supply= 5 volts: Concentration measured across R1 and R2 and currents through each LED Figure 7. Power supply= 2 volts: Voltages assessed across R1 and R2 and power through every single LED Table 1 . A comparison of Pre-Lab ruse and genuine Lab data Looking at the comparison chart above you observe that the ac electricity and the total current was close in value when viewing the Pre-Lab and the Actual Lab.
Using the Multisim ruse charts are printed and attached to this lab survey. Looking at the comparison graph above you observe that the ac electricity and the total current was close in value when viewing the Pre-Lab and the Real Lab. You see, the Multisim ruse charts will be printed and attached to this lab statement. Conclusion: To conclude when simulating the routine in actuality or perhaps in Multisim, the LED voltage, current, and brightness are affected by the decreasing from the voltage supply. By lessening the volts supply the illumination of the LEDs also reduction in intensity.
When determining the factors that are involved in the lighting of the LED we must consider the circuit and see if the resistors and the LEDs happen to be connected correctly. We must as well look at the value of the current passing through the current. To determine the current through the LEDs Ohm’s Law was applied. To find the current we must 1st measure the volt quality and the level of resistance, and then after finding all those two ideals we separate the ac electricity by the level of resistance. Which Ohm’s Law is definitely I (current) = Sixth is v (voltage) as well as R (resistance).
After choosing the current in the LED it can be seen the current is almost equal to the resistor that may be closes to this LED. My spouse and i am in agreement with the measurement that was taken for the voltage flow of 8 volts, 6 volts, and 4 volts, yet I don’t agree with the principles for the voltage flow of 2 v. The measurement collected in Multisim fo and the actual measurement value more the other volts supply ranges. When the LEDs were reversed the resistor and the LED current and their voltages converted to O or perhaps , r’ due to there were zero or any flow of current and voltage.
The voltage is what supply strength to the elements in the routine. So decreasing the amount of ac electricity will cure the amount of one’s current, as well as the amount of current is actually determines the intensity from the LED. The pre-lab appeared to simulate more accurate values than the results from the values in Table 1 . Due to the fact that there is certainly more man value in the actual measurements than the controlled ones, as well as the actual principles have been round and rounded again. The simulated and actual beliefs are very close in value, but do to individual error the values are certainly not and can not be precisely the same.