Last Updated on October 10, 2024 by Alice Benny
Before you can successfully hook up a generator to your home electrical system and power your main appliances and other hardwired electronics, you need a generator transfer switch.
Learn about generator transfer switches, including what they do, why you need one, and how they work.
Generator Transfer Switches
Before you purchase a generator transfer switch, you must learn how it works along with the different types.
How Does a Transfer Switch Work for a Generator?
Transfer switches serve a few purposes. For one thing, they help to isolate the power produced by your generator from the power received by the utility.
That prevents your generator from affecting your electric bill, and from being redistributed to neighbors like solar panels can do.
Depending on your transfer switch, they can also detect a power outage and kick your generator on so that you have little or no service interruption. Assuming your generator has fuel, of course.
Your transfer switch will also detect when your normal electric service has kicked back on.
It tests for a predetermined amount of time before telling your generator to switch off and return to your utility service, so you’re protected from power blinks and repeated surges.
Do You Need a Transfer Switch for Generators?
If you want to keep your family safe and use a generator to get you through the next power outage in your neighborhood, yes, you need a transfer switch.
Transfer switches are not only a critical piece of infrastructure that you need to make it easier to hook your generator into your home power system, but they are also an important safety feature.
It is technically possible to use a simple piece of equipment, like an extension cord, to hook a generator into your home electrical system, but it isn’t a good idea.
Extension cords aren’t designed for this use, and you risk a potential back feed using one.
Transfer switches are also the only way to use a generator to power a hardwired appliance.
That means most critical appliances you and your family use can only be powered with a transfer switch that’s installed properly and safely on your property.
Think of your water heater, any built-in dishwasher, or a built-in cooktop. These appliances are all hardwired.
Worse, trying to hook a generator directly into your circuit breaker without a transfer switch is an incredibly dangerous job. The amount of power involved is potentially fatal should any number of potential problems go wrong.
In addition to transfer switches, if you’re considering getting a home generator, you should take the time to learn the other safety precautions your generator needs.
What Are the Different Types of Transfer Switches?
Here are the transfer switches you can consider buying for your generator:
1. Open Transition Transfer Switch
Open transfer switches completely break the connection from one circuit before connecting to the other. This helps prevent any kind of back feeding into your utility service.
There is a split second of complete disconnection when you’re using this kind of transfer switch.
The length of the disconnection may not be long enough for you to notice it, but it can contribute to additional wear on your electrical system and appliances.
While this kind of transfer switch is great for emergency use, you may want a smoother transition style if you live somewhere with frequent power blackouts.
2. Closed Transition Transfer Switch
This transfer switch makes contact with the new circuit before breaking contact with the old circuit. It eliminates the momentary loss of power typical of open transition transfer switches.
However, the make before break style of contact requires that both power sources be compatible.
They also need to be well synchronized for your transfer switch to operate this way. Otherwise, it will default back to an open transition switch.
3. Soft Loading Transfer Switch
This kind of switch allows your utility and your generator to synchronize. This style helps to minimize voltage variance during the switch.
4. Static Transfer Switch
This kind of switch doesn’t use any moving parts; instead, it uses powered semi-conductors to switch between different power sources and circuits.
Since there are no moving parts, there is a significant reduction in the amount of time required to switch between different power sources.
You’re relying on the speed of an electrical system instead of the limitations of mechanical movement.
Installing Transfer Switches
Installing a transfer switch for generators comes with requirements to ensure safety and proper functioning. We’ve answered important questions related to installation to give you an idea.
Do I Need a Permit to Install a Generator Transfer Switch?
Generally, the answer to the common question “Do I need a permit to install a generator transfer switch?” is a yes. Most areas do require that you get a permit to make any kind of permanent addition to your home.
Some places may have a more extensive permitting process, while others require a permit essentially to make sure the city has an accurate record of the features and amenities in your home.
This is another area where you can potentially rely on a professional electrician to make sure you have everything you need.
Many professional electricians will offer to handle permitting for you and get your signature on any documentation as needed.
Not all electricians offer this service, though. You should always contact your electrician before assuming that they will handle permits.
Otherwise, you might not be able to get your transfer switch installed during your original appointment.
How Much Does It Cost to Install a Generator Transfer Switch?
The cost of installing your transfer switch varies from place to place and electrician to electrician. It might even vary based on the kind of transfer switch you want to install.
Installation for most transfer switches should take between two and four hours. Assuming a relatively average cost of labor, that means about $200 to $400 dollars in labor costs. That doesn’t mean your installation will cost that much.
To answer how much it cost to install a generator transfer switch, you’ll need to contact electricians in your local area.
It’s often worth calling around and getting an estimate on the labor costs from several local electricians if you’re trying to get the best price.
Make sure you know what kind of transfer switch you’re getting installed before you call.
Any other details about your generator (if you already have one) or your home electrical system may also be useful when asking for estimates.
If you contact a master electrician to handle the installation of your transfer switch, you’ll pay more in labor costs than if that same electrician sent an apprentice to handle the job.
You may also see higher labor costs if you live somewhere with a higher cost of living since the costs of labor often largely depend on how much it costs to live and operate in your local area.
How Far Can a Generator Be from the Transfer Switch?
There isn’t a hard and fast distance that marks the difference between safe and unsafe distance for your generator.
The Standard
Most generators are safe up to about 60 to 70 feet away from the transfer switch. That extra distance can help cut the generator’s loudness. It can also help you place the generator somewhere less noticeable on your property.
It’s worth noting that electricity tends to get weaker over distance.
As such, while you might not be pushing a safety concern, you may be losing some of your generator’s power if you place it too far from your home.
Putting your generator further away from your home can also make it more difficult to hear it struggling, or other tell-tale signs of a generator operating beyond its capacity or is likely to need replacement soon.
The further away your generator is, the higher the risk of the connection itself failing.
Cords aren’t perfect, and longer cords and connections are more likely to develop weak spots over time, get cut on accident, and more.
So, generally, you want to find a good medium between finding a safe distance for your generator, and not placing it too far away.
Unfortunately, that job can get more complicated since your transfer switch needs a relatively specific placement. You can’t just hook it up anywhere.
An Important Consideration
You also need to consider how close to any windows or air intake your generator is. Your generator needs to be at least 15 feet away from any windows and needs to be in an open area.
Otherwise, you risk carbon monoxide poisoning when the generator is on.
This distance consideration is more important than how far a generator can be from the transfer switch since it’s a matter of safety instead of efficiency.
Always place your generator at least 15 feet away from entrances and windows, even if that means putting it a little further from the transfer switch.
Can I Install a Generator Transfer Switch Myself?
Technically, yes, you can install a generator transfer switch on your own, assuming you have the necessary experience working with electronics and are comfortable doing it.
If you’re asking yourself “Can I install a generator transfer switch myself?“, also make sure you’re asking if you’re confident working with live terminals and other tricky electrical appliances.
Most of the time, we recommend getting an electrician since installation isn’t that costly. Professionals most often have more specialized equipment and know-how that makes the whole process safer.
However, there are times when getting an electrician is a less practical choice.
To do this, you need to know what circuits you want to power with the generator before you start the process.
You also need to estimate what wattage those circuits need and know whether you are supplying power to 120V or 220V circuits.
You may also need to contact your electric provider since you’ll be working directly in your main service panel box. Some utilities restrict access to professionals for safety and liability reasons.
What Are the Best Transfer Switches?
Getting the best transfer switches makes it easier for your electrician to install, saving you labor costs and cutting down on disruption in your home.
Electricians will often tell you that some of the excellent transfer switches come from Reliance Controls. Not only are they reliable, long-lasting, and supremely safe, almost all electricians have worked with them before and are familiar with the installation process.
That said, they aren’t the only good transfer switch manufacturer. If you’re looking for an alternative, consider Connecticut Electric, Generac, or Reliance Products.
As another option, you can also contact an electrician to see what products they recommend and what transfer switches they’ve worked with before.
Contacting a local professional will help make sure you’re working with equipment that local professionals know and can maintain.
It also helps to ensure that you’re getting a transfer switch that works well with the types of in-home electrical systems common in your area.
Generator Transfer Switches to Consider
Of course, if you’re looking for a shortlist of some of the best options, here are two that you should consider.
1. Reliance Controls 10-Circuit Indoor Transfer Switch
Reliance Controls 51410C Pro/Tran 10-Circuit Indoor Transfer Switch is a good option for professionals and DIYers alike. It’s quick to install and cuts down any complications that may come from installation.
Its maximum capacity is generators with 12,500 running watts. It has 10 maximum single-pole circuits and five maximum double pole circuits.
That capacity is just about right for most American homes, able to run built-in appliances as well as some conveniences and lights.
The powdered steel construction is safe, durable, and long-lasting. While it’s not particularly attractive, it will fit right in with the other electrical equipment in your home.
It also has the added safety benefit of non-defeatable double-throw switches.
At only 12.6 pounds, it is relatively easy to maneuver during your initial installation, though you may still want a second pair of hands to make it easier.
This option is a good choice if you have a beefier generator or are looking to power a large percentage of your home appliances and equipment with your generator. This isn’t a good choice for smaller systems.
2. Reliance Controls Corporation Six-Circuit Pro/Tran Transfer Switch Kit
If you have a slightly smaller home or are looking for a more restrained generator system, this is a good option.
Reliance Controls Corporation 31406CRK 30 Amp 6-circuit Pro/Tran Transfer Switch Kit for Generators is 7500 Watts.
It’s a little more affordable than the larger transfer switches, but that also comes with smaller capacity as well as fewer circuits.
That said, this system is also significantly more efficient if you have a smaller generator.
While you might not be able to run all circuits in your home with this transfer switch, you can run the most important appliances, your lights, and other critical conveniences.
The transfer kit also comes entirely pre-wired. That means less work for you or your electrician, making it cheaper either way.
The 10-foot power cord also gives you a little more placement flexibility, which provides you with more options when installing the transfer switch on your home.
It also has a five-year warranty for peace of mind that your system will hold up well and reward your investment.
It’s also worth noting that both of these transfer switches are from Reliance Controls, our top recommended manufacturer.
How to Choose the Right Transfer Switch
Even with our recommendations about, knowing what to look for in a transfer switch is essential. It will ensure you get a unit that will work for your generator and home.
1. Wattage
One of the first things you need to consider is that if your transfer switch can manage the highest capacity of your generator.
You might have a generator that’s more powerful than you really need, but as you expand your use, you need to make sure you don’t also have to upgrade the transfer switch.
Try not to buy either a generator or a transfer switch that goes too far above what you need. Too much extra power isn’t efficient and can cause problems down the line, as well.
2. What’s Included
You should also consider what you get, and what all is in the kit you purchase.
Reliance Controls are good about providing all of the wiring and accessories you are likely to need, along with longer cords and other advantages that makes installation much simpler.
You should also look for a transfer switch that is already fully wired internally unless you specifically need an odd configuration.
It will also cut down on your work and save you labor costs if you hire a professional electrician.
Spare parts can also be an advantage, though they are somewhat less common than other benefits.
Avoid transfer switches that don’t come with all of the cords you need or that are only partially put together.
3. Manual vs Automatic
It’s also worth considering whether you want a manual or an automatic transfer switch.
Manual transfer switches tend to be a good bit cheaper than automatic transfer switches.
They are also a good bit easier to install and work better for portable generators. However, manual transfer switches need you to come out and change over the power source every time there is an outage.
Automatic power switches are usually a little more expensive. They are also slightly more complicated and can mean a more difficult installation.
However, for non-portable generators, they work better and help to reduce any electric interruptions from an outage.
The main downside of automatic transfer switches is that they are considerably more expensive than manual versions.
It’s worth asking yourself if the added convenience is worth hundreds of dollars more expensive upfront. For most people, a manual transfer switch will work better and be a more cost-effective option.
How Long Will a Generac Generator Last
Ready to Get a Transfer Switch?
Transfer switches are a critical component of any safe and effective generator setup.
If you want to connect your generator to your home, you absolutely need a transfer switch to make the connection stable and secure.
Like generators, there are different types, but Reliance Controls produce some of the most popular and consistent models.
If you don’t want to spend a lot of time shopping around, you’d do well to go with them.
You also need to match your transfer switch to your generator. If you don’t know what kind of generator you need quite yet, this guide covers some of the best generator options out there. Getting a generator is a fantastic first step to power outage preparedness and ensuring your family is well taken care of in any situation.
It’s very important to know that a LICENSED ELECTRICIAN is best because YOUR INSURANCE COMPANY has an excuse and will not pay for a claim because you didn’t GET A PERMIT or use a LICENSED electrician ♂️.
I learned THE HARD WAY!
I should have spent the money, got the permit and have it installed by licensed electrician.
The TS-30 Transfer Switch is part of our travel trailer project, which also involved the installation of a 3,000-watt inverter. With this switch, there is no momentary power loss when switching between primary and secondary or return power sources. It’s pre-wired so all I had to do was plug everything in. The purpose of the ATS is to cut back to the “Grid” power in the event the inverter drains battery power and/or if the solar array creates an overvoltage condition that forces the inverter to shut down.