What is the name of the plate where the wires on a thermostat get attached?

The correct answer is the sub-base because it is specifically designed to provide a secure point for the thermostat wires to connect. The sub-base acts as an intermediary between the wall and the thermostat, facilitating the connection of various wires that correspond to the heating and cooling systems in a home or building.

This plate is essential as it helps to organize and support the wiring connections necessary for the thermostat to function properly. Additionally, the sub-base ensures that the thermostat is installed at the correct height and orientation, leading to accurate temperature readings and effective system control.

In contrast, the main panel typically refers to the central control unit of the electrical system in a building, not specifically for thermostat installations. The mounting bracket might be involved in securely attaching the thermostat to the wall, but it does not serve the purpose of connecting thermostat wires. The control board is generally found within HVAC units and handles the operation of the heating and cooling systems themselves, rather than acting as a connection point for thermostat wiring.