Transfer Switch for Backup Power

If you want safety and convenience when you use a generator in your home, install a transfer switch for backup power.  You cannot safely plug the generator output into your home circuits without a transfer switch handling the electrical traffic.   Although you might choose to use an extension cord from the generator to plug in appliances, that is such a bother it’s hardly worth it.

What Does a Transfer Switch Do?

A generator transfer switch closes off the utility power line to your home’s electrical system during a power outage and opens a line to a generator.  When normal power from the utility is restored, the switch reverses the process.

A transfer switch is normally located near and permanently hard-wired into the breaker panel in your home.   It eliminates a problem called back feeding, which means that electricity runs back out of the house and toward the transformer.   Unless the backup generator is large enough to power all the circuits in your home, the transfer switch will be wired only to those essential circuits you choose such as some lights and the heating-cooling system.

Types of Transfer Switches

All transfer switches allow you to change the incoming supply of electricity so that it comes from the utility company or from the generator.

  • Manual switches only work when a human physically makes a change by moving the position of the switch on the box.  This type of small transfer switch could work for powering a furnace circuit. If your generator requires someone to physically start it, then a manual transfer switch is a sensible choice since you could start both at the same time.  However, if no one is home when the power goes out, the switch will not change, backup power will not come on, and the manual system will not fully protect your home.
  • Alternatively, automatic switches do not require any human interaction, they make the change by themselves when they detect a drop in incoming voltage from the utility company.   As long as the generator has an automatic starter, backup power will come on without any human action.   It will also turn the generator off and change back to the utility when it senses that line voltage has been restored.   A sample image of an Eaton automatic switch is shown above.

How Much do they Cost?

Transfer switches can be purchased for as little as a hundred dollars and can range up into the thousands of dollars.   The switch you need will depend on the generator you choose as they need to be sized the same.

If you need assistance with making your decisions about a generator and a transfer switch, we’d be glad to help.   Just contact us and we’ll provide the information you need to make a good choice.

Remember – Do not try to use an extension cord or wire a generator directly into a service box.  Connecting a generator to a home service requires a licensed professional who can make the connection safely.

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