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Portable Generator Transfer Switch – The Guide for 2022

So you want to use a portable generator as a home backup power supply in the event of emergencies. This is a wise precaution measure that will save you a lot of headaches next time the power outage affects your area.

Apart from the portable generator, you need one more important accessory to make your backup power system work.

It’s the generator transfer switch.

A transfer switch allows you to connect a portable generator to your household circuit breaker.

It makes it possible to power all critical appliances permanently connected to your house grid.

These include the refrigerator, freezer, window air conditioning units, and the lighting circuits.

It’s also the only bulletproof solution following all building codes and safety measures.

If you are in a hurry and simply want to know which transfer switch is the best match for a portable generator – check out this 30 Amp Manual Transfer Switch by Reliance Controls Corporations.

If you are in a hurry and simply want to know which transfer switch is the best match for a portable generator – check out this 30 Amp Manual Transfer Switch by Reliance Controls Corporations.

This transfer switch supports generators of up to 7500 watts and is by far the most popular choice for homeowners.

Do you need a transfer switch for a generator?

If you want to be 100% sure your portable generator will get your family and home safe throughout the next power blackout then yes – you need a transfer switch.

There are plenty of people asking “How to connect a generator to the house without a transfer switch?”

While it is technically possible to hook up a portable generator to a house using an extension cord without a transfer switch – we DO NOT recommend doing so at all.

This is for a few major reasons:

Safety precautions

Connecting a portable generator to a house without a transfer switch can be a dangerous affair.

In such a case, if you hook up a portable unit via an extension cord and turn it on during the power outage, it will keep running even when the power is restored in the grid.

The power would then go back down the line to the generator resulting in the back feed.

This could not only damage the generator and your household appliances but also cause fire or electrocution.

Hooking up a generator to your home circuit breaker without a transfer switch could be potentially fatal.

Unless you are a skilled electrician who knows exactly what they’re doing, for your own safety do not attempt to use a portable generator to run your household without a transfer switch.

The only way to power hardwired appliances

A transfer switch is the only 100% safe way to run the major appliances connected to your circuit breaker panel.

These include things like built-in dishwashers, cooktops or water heaters.

You can’t run these if you don’t have a transfer switch installed.

So what is the best transfer switch for the generator?

The best transfer switches for portable generators are made by Reliance Controls Corporation.

Any skilled electrician can testify that these switches are by far the most trusted and popular choice.

You will see them installed in a lot of American households.

You won’t have any problems finding a professional electrician to install a transfer switch made by Reliance Controls, since they all likely know these switches very well.

For Generators up to 7500 Watts

The Reliance Controls Corporation 31406CRK 30 Amp Transfer Switch is the right fit for generators up to 7500 watts.

This is currently by far the most popular transfer switch on the market.

It has already received more than 600 five star reviews from buyers on Amazon.

The kit contains all accessories needed for the complete installation of the transfer switch.

These include the 10 feet long power cord, PB30 outdoor remote power inlet box, wire nuts, and the male plug for 20 amp generator outlets.

It is the perfect transfer switch for generators with a maximum running wattage of 7500.

To give you some examples of what generators are compatible with this transfer switch – the Westinghouse WGen7500DF is one of them.

This unit has got the starting wattage of 9500 and the running wattage of 7500.

That makes this and any smaller generators 100% compatible with this transfer switch.

For Generators up to 12500 Watts

If you are planning to run a heavy-duty 12000 watt generator to power nearly the entire household – this Reliance Controls Transfer Switch is the one you should get.

It would be the right match for ultra-duty generators like Duromax XP10000EH.

This unit features a steel cabinet, resettable circuit breakers, 6 combination knockouts,
and double-throw switches.

How To Choose the Right Transfer Switch

There are a few major factors you need to take into account when buying a transfer switch.

1. Wattage

Make sure you get a transfer switch that can handle the rated wattage of your generator.

Eg. if you have a generator capable of providing up to 7500 running watts, get a transfer switch supporting generators up to 7500 watts.

If you haven’t bought a generator yet and you aren’t sure what size of a generator do you need, check out our calculator to get the rough estimate.

2. What’s in the kit

Most of the reliable manufacturers such as Reliance Corporation sell the transfer switches complete with all accessories needed for their installation. This eliminates the need to purchase any additional parts.
However, it won’t harm to doublecheck if this is indeed the case with the transfer switch you are willing to purchase.

This would save you from any unpleasant surprises or additional costs when the electrician arrives to install it.

3. Type

There are two common types of transfer switches: manual and automatic. Both have their pros and cons.

However, for most of the homeowners, the manual switch would be the most recommended solution. We explain why below.

Should You Get a Manual or Automatic Transfer Switch?


  • Best choice for portable generators
  • Cheaper – manual transfer switches cost a fraction of the price of automatic units. If you think that you are only going to use the generator a few times a year – getting a manual switch could be a reasonable cost-effective decision
  • Easy installation – manual switches require significantly less effort to install which makes them even cheaper to buy and set up as you won’t have to spend that much money on the electrician’s time
  • Just like the name suggests, every time there is a power outage, you need to flip the switch manually in order to make the generator run your home. However, flipping the switch is a very easy task and does not require any specific knowledge.


  • Designed for standby generators
  • If you are looking for a hand-free approach and want your generator to power up your home almost automatically without needing to mess around with the transfer switch – the automatic type is the right way to go.
  • Automatic transfer switches save you the hassle of having to flip the switch every time there is a blackout. All you need to do is simply turn on the generator and you’re good to go.
  • A typical automatic transfer switch is usually more expensive than a manual transfer switch. You need to ask yourself whether you want to pay much more for the transfer switch if you are only expecting a few power outages a year. A good quality automatic transfer switch can cost more than 1,000 dollars which is more than the price of a decent portable generator!
  • Those kinds of switches are generally designed for whole-house standby generators and are not the most recommended choice if you intend to use it along with a portable generator

My Verdict

If you need a transfer switch for a portable generator - go with the manual transfer switch. While it might sound like a bit more of the hassle first, it gives you better control over what is powered by a generator and what is not in case of an emergency. It’s also a much more cost-effective solution.

Do I need anything else to connect my generator?

One more accessory which is not always sold together with a transfer switch is a power cord.

It is often included in the kit with most of the generator transfer switches. However, if you realize this is not the case, make sure you purchase the right type of power cord.

For portable generators, it should be a 30 amp cord. You can tell the amperage by the number of male prongs - it should be 4.

Make sure to also take the length of the extension cord into account. If you are planning to place your generator far from the transfer switch, a long extension cord is a must. Bear in my mind that those which are sold together with the generator transfer switches are sometimes quite short.

How to install a manual transfer switch?

We recommend hiring a certified electrician to perform the installation of the transfer switch.

However, if you are confident about your DIY skills, you can check out this comprehensive guide by Electrical Engineering Portal. It explains step by step what you need to do when installing a manual transfer switch at your home.


Do I need a permit to install a transfer switch?

Technically yes, you need a permit from the local authorities whenever you install any permanent additions to your house. Generator transfer switches are no exception.

However, if you hire a certified electrician for the installation, they will usually be able to sort out the permits on your behalf.

How much does it cost to have an electrician install a transfer switch?

The costs of hiring an electrician can vary a lot depending on where you live, your house structure, etc. As a rule of thumb, it should take them around 3-4 hours to perform the whole installation of a transfer switch and cost up to $500.

It's not uncommon though for homeowners to pay as little as $200 for the whole set up. That's why it's a wise idea to go with a recognized brand such as Reliance Control since most electricians know these switches extremely well and can install them quickly, saving you money on their labor costs.

How far can a generator be from the transfer switch?

There is no fixed maximum for how far the generator can be from a transfer switch. You shouldn't have any problems placing it 60 - 70 feet away from the transfer switch.

9.5 Total Score
Reliance Controls - best transfer switches for portable generators