Installing a Manual Transfer Switch
How to Select the Right Generator Transfer Switch: How to Save Money on a Generator Transfer Switch – These two items actually work hand in hand, and the end result will actually be how large the generator will be and there are a few more options that may be much easier to install and much less costly that a large transfer switch.
Home Generator Transfer Switch
- While an electrician will do work to be safe, we would like to know what is required.
- Issue is the house has two (2) electrical panels > main enters into a 125 amp panel, then feeds across house to another 40amp panel.
- Can we use a 100 amp or require a 200 amp transfer switch?
This Home Generator Electrical Question came from: Ted, from Kensington, Connecticut.
Thanks for your Electrical Wiring Question Ted.
Installing a Generator Transfer Switch
Application: Generator Transfer Switch.
Skill Level: Advanced – Best installed by a Licensed Electrical Contractor.
Tools Required: Electricians pouch of hand tools and the various power tools necessary for installing the generator and transfer switch.
Estimated Time: Depends on the type and size of the generator and transfer switch and the available access to the project area.
Precaution: Any existing electrical wiring within the immediate area that may interfere with the installation of the transfer switch may need to be relocated if necessary. The selection of the transfer switch or generator connection or generator circuit panel will affect the over all project.
Important: Installing a generator, transfer switch or generator panel must be well thought out and performed with a permit with all work being inspected.
Electrical Code Compliance: Generators and transfer switches should only be installed with a permit and inspected. A generator project is best installed by a Licensed Electrical Contractor.
How to Select the Right Generator Transfer Switch
The process of choosing the type and size generator transfer switch depends on two things:
- What size the generator will be, specifically the volts and amperage rating and capability.
- The actual load that will be placed on the generator.
These two items actually work hand in hand, and the end result will actually be how large the generator will be. Once the size of the generator is known then the type of transfer switch may be selected, and if the size of the generator is not that large then there are a few more options that may be much easier to install and much less costly that a large transfer switch.
Factoring in the Size of the Electrical Service or Panel
If a manual transfer switch will be installed then the size of the transfer switch must be rated as the same size as the electrical service that will be brought into and switched by the transfer switch, regardless of the size of the generator. So, if the generator power will be providing power for a 240 volt 125 amp panel then the transfer switch must be rated for at least 240 volts 125 amps.
Generator Transfer Switch Options
How to Save Money on a Generator Transfer Switch
- When a generator is rated at 240 volts and 60 amps or less then a UL Approved Circuit Breaker Interlock Kit may be installed if one is available and compatible with the electrical panel.
- The point is this, there is no reason to install a large transfer switch if the generator will not produce a large amount of power and there are options for installing one of these other interlock systems or a smaller generator circuit panel.
- However, if you are planning to have the whole house on full power and a larger generator will be installed then yes, you will need a large transfer switch that is rated the same as the home electrical service panel.
More about Generators and Transfer Switches
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This series covers a wide variety of topics all about home generators including sizing, selecting, connecting and safely operating this all important addition to your home.
The Importance of a Generator Transfer Switch
Generator Questions and Answers
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