Whole House Generator Wiring Diagram

whole house generator wiring diagram

If you are a home owner who wants to protect your family from power outages, you have many options. One of them is a whole house generator.

They can be a good investment for homeowners, as they help prevent loss of electricity, and can increase the value of your home. But, they also have a few drawbacks.

Automatic Blackout Detection

Automatic Blackout Detection means that your generator will immediately start up if it detects power outages, eliminating the need for you to walk outside and manually activate it. That’s a critical safety feature.

Brownouts, which are less common than blackouts but can still occur, are temporary voltage sags that are intentionally imposed by energy providers as an emergency measure to prevent the system from failing completely (blacking out). They have minimal impact on most heat and lighting systems, but they may damage sensitive electronic equipment, such as computer disk drives and electric motors.

Rolling blackouts, which are much more common than brownouts and can affect a large part of the country, are controlled and usually preplanned interruptions of service. They are typically implemented by your utility company in response to weather events that can cause a demand and supply imbalance.

Because of this, it is important to understand what these outages are and how they can be prevented or reduced. For example, you should follow the news for weather threats and report any planned outages to your power company to keep them aware.


Auto-Start is a technology that provides automatic operation for a generator when utility power is down. It does so without sacrificing essential circuits, such as lights and air conditioning.

To turn on a generator in the event of a blackout, simply press the auto-start button on the controller. The system will automatically crank the engine, connect load circuits to the standby side and transfer loads when utility power is re-connected.

You can also choose to set a quiet time to prevent noise from arising during generator operation. This can be enabled through the Enphase Installer App.

To wire a generator to the home, you need to connect the 2P and SP breakers from the main panel to the generator transfer switch using the wiring diagram below (or according to user manual). The transfer switch will then transfer the generator breaker to the load points and the power will flow from there to all load appliances.


A transfer switch is a key component of a whole house generator. It connects to essential circuits and provides a power feed from the generator into your home, so you can use appliances that cannot be run using an extension cord.

Aside from powering these essential loads, the switch also prevents backfeed of utility power to the service panel when the generator starts up, which can be dangerous for line workers and could lead to damage. This feature is a safety benefit that many municipalities insist on when hooking up a whole house generator.

Auto-Shutoff is a feature that automatically shuts down your generator after a specified time period has passed without supplying power to the system. Its activation is triggered by an app-based setting that you can select from in the Dask cluster configuration menu.

To enable Auto-Shutoff, first connect an AC voltmeter test lead across the E1 and E2 lugs on the generator. If the voltage is correct, disconnect the test lead from the generator and disconnect utility input (main breaker) from the transfer switch for 3-5 seconds and reconnect. This will clear the warning display.