LAB 1 - INTRODUCTION TO DC CIRCUITS

Goal: To determine the maximum cable resistance so that the battery source would still be able to deliver enough voltage to operate an electronic device (load) normally from a distance. After the maximum resistance is determined, the maximum distance would also be calculated assuming the AWG #30 wire is used.

Experiment:

From the given information, resistance of the load (Rload) can be calculated:

Using the calculated Rload, a circuit was assembled. A 1000 ohms resistor was used to represent Rload. A resistor box was used to represent resistance of the cable (Rcable). Setting Rcable to 0 ohms, the measured Vbattery was 11.91 V and Ibattery was 12.23 mA (0.01223 A).

After Rcable was adjusted, the maximum Rcable was determined to be 80 ohms. The measured Vbattery was 11.02 V and Ibattery was 11.32 mA (0.01132 A).

After data was collected, time to discharge, power to the load (Pout), power to the cable (Plost), efficiency, and the maximum distance between the battery and the load were calculated assuming the AWG #30 wire with resistance of 0.3451 ohm/m was used.

Data Calculations:

Conclusion: The maximum cable resistance to still be able to operate a distant electronic equipment normally was found to be 80 ohms. Depending on the wire used, the maximum distance may vary. In this case, AWG #30 wire with resistance of 0.3451 ohm/m was used, and the maximum distance was determined to be 116 m.