What Is a Transfer Switch for a Portable Generator for Homes?

The device that transfers power between the main source of power for a home and a portable generator is a mechanism called an electrical transfer switch. These switches operate manually or automatically but can also work using a combination of human intervention and automatic response.

Function

Electrical transfer switches provide homeowners with the ability to safely switch the source of a home's power from the local utility company to a portable generator. Once the main power line is available, the switch can then reverse the action and resume the home's use of power from the local utility company.

Significance

Power outages, surges or other problems with a home's main source of energy can all necessitate the use of a portable generator. When it is necessary to switch between the utility company and the generator, the electrical transfer switch keeps the two power sources isolated from one another. This permits the power to be transferred safely, without the risk of current traveling between the two sources.

Automatic

Automatic transfer switches constantly monitor levels of electricity and transfer power between sources when necessary. These switches accomplish many functions. They monitor power and evaluate the voltage levels, as well as power up the generator in advance of switching power. Once power has been switched, automatic transfer switches continue to monitor the main line until they have ascertained that the power is once more stable. At that point, they switch power back from the portable generator to the main power line.

Manual

Transfer switches that offer no monitoring of voltage levels and require human action are called manual transfer switches. These switches require a person to transfer the power between sources by hand, after powering up the generator. They also require manual intervention to switch the power back, once the main line is functional once more.

Combination

There are electrical transfer switches that offer both automatic and manual controls to switch power between a main utility line and a portable generator. This combination typically maintains processes that have been designated as critical on an automatic transfer switch. All other electrical transfers are accomplished with a manual switch.