Final answer:
The service drop for a residence is connected to the utility company's secondary voltage, which is the lower voltage suitable for household use, stepped down from the much higher primary voltages used for long-distance transmission.
Step-by-step explanation:
The service drop for a residence is connected to the utility company’s secondary voltage. Power in electrical systems is typically generated at a high voltage (exceeding 10 kV) and then transmitted over long distances at even higher voltages, often ranging from 120 kV to 700 kV, to limit energy losses. When electrical power needs to be distributed locally, it goes through a substation where it is stepped down to lower voltages, generally ranging from 5 to 13 kV. Before the power enters a residential home, it is stepped down further to safe consumable levels such as 240 V or 120 V, which is known as the secondary voltage. This is in contrast to the primary voltage used in high-voltage transmission along power lines, which is far too high for safe direct use in homes.
It is also important to understand the relationship between primary and secondary voltages in a transformer. A down transformer is used to reduce the voltage from the primary (high) side to the secondary (low) side. Consequently, primary voltage is higher than secondary voltage, which helps in decreasing the current through the power lines and subsequently reducing the power loss during transmission.