Concept explainers
In the diagram, Load A is rated at 10 amperes, 120 volts. Load B is rated at 5 amperes, 120 volts.
- a. When connected to the 3-wire branch circuit as indicated, how much current will flow in the neutral conductor? __________________
- b. If the neutral conductor should open, to what voltage would each load be subjected, assuming both loads were operating at the time the neutral conductor opened? Show all calculations.
a.
Find the amount of current that flows in a neutral conductor when a circuit is connected to a 3-wire branch circuit.
Answer to Problem 4R
The amount of current that flows in the neutral conductor is
Explanation of Solution
Given data:
The values of current and voltage at Load A are
The values of current and voltage at Load B are
The total voltage of the system is
Calculation:
From the given data, the values of current to Load A and Load B are not equal. Therefore, it is an unbalanced load.
For an unbalanced load, the current through the neutral conductor is calculated as follows:
Substitute
Conclusion:
Thus, the amount of current that flows in the neutral conductor is
b.
Find the voltage of each load when the neutral conductor is open.
Answer to Problem 4R
The voltage of Load A is
Explanation of Solution
Formula used:
Write an expression to calculate the resistance.
Here,
Calculation:
Substitute
Substitute
When the neutral conductor is open, Load A and Load B are connected in series. Therefore, the total resistance is calculated as follows:
Substitute
Rearrange equation (2) to find
Substitute
Rearrange equation (4) to find
For the series connected load, the current is same for both Load A and Load B.
Substitute
Substitute
Conclusion:
Thus, the voltage of Load A is
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- EBK ELECTRICAL WIRING RESIDENTIALElectrical EngineeringISBN:9781337516549Author:SimmonsPublisher:CENGAGE LEARNING - CONSIGNMENT