Transfer Switches For Portable Generators

A transfer switch prevents electricity from flowing simultaneously between your portable generator and the utility grid. It is mounted next to your home circuit breaker box and can operate manually or automatically.

In the event of a blackout, you can power several appliances to include the refrigerator, television, lights and even your sump pump. However, you must first position the generator into place no less than 15 feet from your home to prevent carbon monoxide consumption.

One way to provide power is to run extension cords from the generator to your lights and appliances. This can be inconvenient and unwieldy while making it difficult to operate some critical circuits like the furnace fan or well pump.

Another way is to connect the portable generator directly to your household wiring by installing a manual transfer switch. This will permit the use of only one cord to provide electricity to several or all of your most important household circuits, including the furnace fan and well pump. Bear in mind the National Electrical Code mandates that a transfer switch be properly installed for safety precautions.

By way of comparison, permanently installed standby generators come with transfer switches that automatically kick in when the utility power goes down. Conversely, the transfer switch for portable generators is an additional cost item that can average $200 to $500 depending on the total circuitry and wattage requirements.

It is highly recommended that you engage the services of a licensed electrician to install the transfer switch and connect it with the main breaker box. Although most transfer kits come with excellent instructions for the do-it-yourself person, you always run the risk of creating a back-feed through the utility lines should you innocently make an error while wiring. This can cause severe damage to equipment, as well as death to those who might be working to restore power in your vicinity.

The transfer switch contains several circuits and the electrician can assign each circuit to a different load. This provides efficient management of usage and extends the effectiveness of the portable generator. When the utility power goes out, you simply plug your generator into the transfer switch, start it up, and flip the transfer switch from the Utility position to the Generator position.

For convenience, you might wish to purchase a remote power inlet box to be installed in a location away from the actual transfer switch unit itself. This would permit plugging into a separate receptacle that is positioned closer to the operating generator. You can then have a shorter and less cumbersome master cord running from the generator all the way to the switch panel inside the house.

In summary, the procedure works like this:

When the utility company power goes out:

  1. Plug the generator cord into the transfer switch or optional power inlet box.
  2. Turn all circuit breakers in the transfer unit to the off position.
  3. Start the generator and give it time to warm up.
  4. Flip the main breakers in the transfer unit to the Generator position.
  5. Turn on the desired circuits individually to prevent overloading the generator.

Once power is restored:

  1. Turn the main breakers in the transfer unit back to Utility Power.
  2. Turn on any other circuits that were turned off.
  3. Turn off the generator.
  4. Disconnect the cords.