Automatic standby generators are most commonly used in commercial situations to deal with cases of unforeseen power outages. They can also be useful for residential applications in order to provide backup power for key systems which the homeowner needs to ensure are running at all times. As custom home builders and renovators we’ve installed many differing systems.

Fuels and generator location

The generator units are designed to run on natural gas or liquid propane fuel supply (diesel versions are also available), and due to their location outside the home they carry a reduced risk of carbon monoxide poisoning when compared to portable generators.

Standby generators are permanently connected to the homes electrical system but they only become active when a unit sensor notices a power interruption lasting longer than about 20 seconds. The generator will then send a signal to a transfer switch located near the electrical panel. This switch, in turn, will disconnect the home from the electrical grid and connect predetermined circuits to the generator, thereby restoring power to specific home systems. Later, when the sensor detects that the regular electrical supply has been restored, the unit will automatically return to standby mode.

Choosing a whole system or a partial system

Whole System: This will provide power to all circuits in a home. Understandably, these units cost more since a larger generator and transfer switch will be required.

Standby-generator

Partial System: This can be sized to power specific circuits such as basic lighting, sump pump, refrigerator, alarm system and furnace. In cases where the homeowner’s activities request more power than the partial system can provide, the generator will trip a circuit breaker and cut power off to the house. The homeowner will then need to reduce the load and reset the breaker.

Most units are designed to start up on their own once a week for approximately 15 minutes, but it’s important to remember that like all combustion motors, standby generators require regular maintenance (including changing the oil for every 50 hours of operation time).

So while a residential automatic standby generator may not have been something you considered for your home in the past, it’s a ‘peace of mind’ solution that you may want to consider in the future.