Next we attached both multimeter cables before the resistor R6 starting with

# Next we attached both multimeter cables before the

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section of experiment one. Next, we attached both multimeter cables before the resistor R6 (starting with the red cable) to measure the current passing through it. A value of 8.39 mA was displayed by the multimeter which represents our measured value. For our calculated value, we calculate equivalence resistance Req = (1 . 5 K// 680) + 1 K = 1467 . 89 ( Ω ) then we calculate equivalence current in that circuit Ieq = 12 / 1467 . 89 = 8 . 175 mA after that I 6 0 = Ieq = 8 . 18 mA because 12V is in series with the resistor R6. In Fig 3 top right, we set up the circuit to calculate the current (I7") passing through resistor R7. However, this time we shorted the 12V voltage source. We attached the multimeter cables after the resistor. A measured value of 2.69 mA was displayed by the multimeter. In addition, for the calculated value, we calculate equivalence resistance Req = (1 K// 680) + 1 . 5 K = 1904 . 76 ( Ω ) then we calculate equivalence current in that circuit Ieq = 5 / 1904 . 76 = 2 . 63 mA after that I 7” = Ieq = 2 . 63 mA because 5V is in series with the resistor R7. Finally, for Fig 3 bottom left, we were required to measure the current (I8) passing through resistor R8. However, for this part of the experiment, we were asked to keep both voltage sources (12V and 5V) attached to the circuit. We then proceeded by attaching the multimeter cables before the R8 resistor. The measured value displayed by the multimeter was 4.15 mA. For our calculated value, I 8 = I 8 0 - I 8” = (1 . 5 K/ (680+1 . 5 K )) * 8 . 175 m - (1 K/ (1 K +680)) * 2 . 63 m = 4 . 06 m . If we take a look at the percentage error columns in table 2, we can observe that the highest percentage error that we 3 got was 3.9 percent. Which means that we were accurate in our measurements. However, the percentage error values in this experiment were higher than percentage error values in the previous one. Figure 3: Superposition Measurements 4.2 Second Experiment Between A’ and B’ Between A’ and C’ Between B’ and C’ M ¸ easured Calculated % of Error Measured Calculated % of Error Measured Calculated % of Error 2.13k 2.14k 0.46 1.68k 1.695k 0.88 0.886k 0.881k 0.57 Table 3: Star-delta Transformation results For this experiment, we used the star-delta transformation formula to calculate the values between the given sockets, and we measured the values practically using the multimeter. The results we captured in table 3 state that our calculations were accurate since the values of the measured and calculated are very close to each other; and since the values were close to each other, the percentage of error came out to be very low. This exercise helps use find the values of resistors that are connected neither in parallel nor series, and we could that both practically and theoretically. Doing it practically  #### You've reached the end of your free preview.

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• Spring '19
• Electrical network, Electrical impedance
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