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Brian Bennet
  Feb 3, 2023 9:31 AM

A generator transfer switch is a device that allows you to seamlessly switch from a utility-provided power supply to a self-sufficient generator system whenever you need it. If you have this device, then your home can be powered by your electricity-generating unit (EGU) in case of an outage or misfortune.

With an increasing demand for renewable energy sources, the need for power generators is also on the rise. Many people opt for generator transfer switches when it comes to solving the “power problem.”


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1. How does the generator transfer switch work?

Think of a generator transfer switch as a miniature circuit breaker that draws power from your generator instead of from the utility company. When there is a power outage in your area, you plug your generator into an outdoor outlet that's connected throughout the house by an internal generator transfer switch.

The generator transfer switch is installed by an electrician, usually next to your main breaker panel. An electrician can help you figure out which circuit you want to power during a power outage. Heating and cooling equipment is needed, as are water heaters and well pumps.

If this switch is installed, you will be able to run outdoor-rated extension cords from the generator into your home. And yes, multiple wires: Since they can be overloaded, you'll need a dedicated cord for anything that consumes a lot of power, like a space heater or window air conditioner. Please also note that you can only power electronic devices with standard plugs without a generator transfer switch. You will not be able to connect anything hard-wired to your circuit board, such as a heater or an air conditioner compressor, and you're out of luck if you have an electric stove or dryer, as both use a large voltage of 220 volts, four-prong plug. A generator transfer switch lets you power any device-and skip extension cords.

Generator transfer switch installation costs usually range from 500 to 1500, usually taking less than a day to complete.

Plan to install early in case you cannot find a worker every time the rainy season comes.

a generator transfer switch



2. Which generator needs a transfer switch?

Backup generators for homes and businesses almost always need one. Since they are always waiting when the power goes out, it is important to have this extra device in place to keep the power going without downtime.

However, portable generators do not really need a generator transfer switch, but that is usually a good idea. The biggest benefit of having a generator transfer switch in a residential environment is that you can power everything through a circuit breaker instead of using an extension cord. This includes hard-wired appliances, such as dishwashers, water heaters, air conditioners, and ceiling fans. All you must do is plug the portable transmitter into the generator transfer switch, and you are good to go!

Is a generator transfer switch necessary?

If your generator is over 5,000 watts, you will always need an on-off switch for safety and ease of use. This is essential to remember, as the level of power generated requires the use of a regulator to help keep the grid free from surges and back-supply.

But what about legal? One of these questions depends on where you want to keep a backup generator. Some jurisdictions make this requirement, while others only suggest that you have one. And others make it mandatory for backup generators.

If you need to know if your local government requires a generator transfer switch, talk to the building law enforcement office. From there, they can advise which generators need a toggle switch and which don't.

a generator transfer switch necessary


3. Risks of not using a generator transfer switch

There are many risks to not using a toggle switch that go beyond simple convenience. In some cases, not having an on/off generator transfer switch could jeopardize the safety of your family.

The main scenario where this becomes an issue is called grid resupply. This means that when you are using a generator without a suitable power switch and mains power is on, there will be two currents supplying your home. This surge could cause problems in the line, which can put utility workers at risk. It can also cause a fire in your home. And that is why having a transfer switch is so important.

Now let's make it clear that we are talking specifically about a backup generator that's wired to a panel in your home or office. If you are using a portable generator and just need to plug a few bulbs or other items directly into the generator, this shouldn't be a problem.

a toggle switch


4. Types of generator transfer switches

There are two different types of generator transfer switches-automatic and manual. 

Automatic generator transfer switches

As the name suggests, the power switch automatically routes power from the mains to the backups seamlessly when needed. It is always there, ready to switch power to the generator when needed.

Automatic generator transfer switches


Manual generator transfer switches

Manual switch requires humans to flip a small lever and turn it on, hence the name. Generators often require manual switches because they are only sometimes plugged in. Permanently installed standby generators can vary between manual and automatic, but automatic is often the most convenient option. After all, who wants to go out into the snow, wind, or rain to flip the energy recovery switch?

For most businesses, automatically switching to backup power in the event of a power outage is desirable, while for some, it is very important.


5. Do you need a permit?

In some cases, you will need a permit to install the switch. However, if you are working with a permitted electrician, they'll usually handle this aspect for you and only charge toward the total cost of the installation. For more information about the required permit type and cost, talk to your contractor or the building law enforcement office in your jurisdiction.

While you may want to omit the switch when installing a generator, the truth is that it is almost a mandatory part of using and owning a backup power source. The only choice you have is to use a manual generator transfer switch or an automatic switch.

Install the generator transfer switch

While you may want to install the on/off switch yourself, having a professional electrician do the work is a good idea. The reason is that the best generator transfer switch had to be installed on your electrical panel box. If you have never done this task or do not know much about the process, trying to do it yourself can lead to mistakes-and when we are talking about electrical currents and fire hazards, if so, then this is not the opportunity you want to take.

Install the generator transfer switch



Remember that proper initial setup is necessary to know how to use the transmitter switch correctly. Make sure to take note of the things outlined in this post before purchasing.

Also, take your time to turn the circuit on or off. Activate or deactivate each of these power distribution devices. Otherwise, you could overload the generator, leading to irreparable harm to the system.

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