3-phase, 3-wire system is used for balanced loads.

Explanation:

- A balanced load refers to a situation where the power drawn from each phase in a 3-phase system is equal. In other words, the current and power are evenly distributed across all three phases.

Advantages of a 3-phase, 3-wire system for balanced loads:

1. Balanced voltage distribution: In a 3-phase, 3-wire system, each phase carries an equal voltage magnitude with a phase difference of 120 degrees. This balanced voltage distribution ensures that the loads connected to each phase receive a stable and equal supply of power.

2. Efficient power transmission: The use of three phases in a 3-phase system allows for efficient power transmission. As the three phases are separated by 120 degrees, the power delivered by each phase adds up to a constant level. This results in a smoother power flow compared to a single-phase system, reducing power losses and improving overall system efficiency.

3. Lower current requirements: In a balanced load scenario, where the loads are evenly distributed across all three phases, the current drawn from each phase is lower compared to an unbalanced load. This reduces the stress on the distribution system and allows for the use of smaller conductors and electrical equipment, resulting in cost savings.

4. Improved system reliability: The use of a 3-phase, 3-wire system for balanced loads enhances system reliability. Since the loads are evenly distributed, any faults or disturbances on one phase will have minimal impact on the other phases. This ensures a more stable and reliable power supply.

In conclusion, a 3-phase, 3-wire system is used for balanced loads due to its advantages such as balanced voltage distribution, efficient power transmission, lower current requirements, and improved system reliability.