Generac 9947 100A 1ph-120/240V Nema 3R Automatic Transfer Switch with 16-circuit Load Center Features:
Generac 9947 100A 1-Phase Automatic Transfer Switch with 16-Circuit Load Center
The Generac 9947 100 Amp 1-Phase Automatic Transfer Switch is designed to automatically transfer selected household circuits from utility power to a compatible Generac standby generator when an outage occurs. Rated for 100 amps at 120/240V single-phase, the 9947 combines an automatic transfer switch with an integrated 16-circuit load center, making it an excellent solution for homeowners who want to back up essential circuits rather than the entire electrical service.
During normal operation, the transfer switch supplies the designated circuits with utility power. When paired with a compatible Generac standby generator, the system detects a utility outage, starts the generator, and automatically transfers those circuits to generator power. Once utility service returns, the switch transfers the circuits back to the utility source and allows the generator to complete its shutdown cycle. This provides automatic backup protection without requiring the homeowner to manually operate a transfer switch.
Unlike a whole-house service entrance transfer switch, the Generac 9947 is specifically designed for essential-load applications. Its integrated 16-circuit load center lets the installer select the circuits that matter most during an outage, such as refrigerators, freezers, lighting, heating equipment, sump or well pumps, internet equipment, and other important household loads. This can be an efficient way to pair a standby generator with a home where backing up every circuit is unnecessary. Generac identifies this model as a non-service-entrance essential-circuit transfer switch.
The 9947 is housed in a durable NEMA 3R enclosure, allowing installation indoors or outdoors while protecting internal components from rain, snow, ice, and debris. Generac's hardened transfer switch control is engineered to provide reliable automatic transfer performance even when the utility supply experiences disturbances such as brownouts. The switch is designed for compatible single-phase Generac generators using an Evolution™ or Power Zone™ 200 controller and is backed by a 5-year limited warranty.
Key Features
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100 Amp automatic transfer switch
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120/240V single-phase operation
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Integrated 16-circuit load center
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Designed for essential-circuit backup applications
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Automatically transfers selected circuits during a utility outage
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Non-service-entrance-rated configuration
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NEMA 3R enclosure for indoor or outdoor installation
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Hardened transfer switch control
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Designed to withstand utility disturbances such as brownouts
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Compatible with qualifying Generac single-phase standby generators
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Designed for generators using Evolution™ or Power Zone™ 200 controls
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Automatic operation requires no manual transfer during an outage
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Allows homeowners to prioritize critical household circuits
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5-year limited warranty
Frequently Asked Questions
What is the Generac 9947 automatic transfer switch?
The Generac 9947 is a 100A, 120/240V single-phase automatic transfer switch with an integrated 16-circuit load center. It is designed to automatically supply selected essential circuits from a compatible Generac standby generator when utility power fails.
Does the Generac 9947 include a load center?
Yes. The Generac 9947 includes an integrated 16-circuit load center. This allows an installer to select which household circuits will receive generator power during an outage instead of transferring the home's entire electrical service.
Is the Generac 9947 a whole-house transfer switch?
No. The Generac 9947 is designed as an essential-circuit transfer switch, not a whole-house service-entrance switch. Its 16-circuit load center is used to supply only the circuits selected for backup power.
Is the Generac 9947 service entrance rated?
No. Generac identifies the 9947 as a non-service-entrance automatic transfer switch. If the installation requires a service-entrance-rated transfer switch, a different Generac ATS should be selected.
Can the Generac 9947 be installed outdoors?
Yes. The Generac 9947 has a NEMA 3R outdoor-rated enclosure designed to protect the transfer switch components from rain, snow, ice, and debris. This gives installers flexibility to locate the switch indoors or outdoors when permitted by applicable installation requirements.
What generators are compatible with the Generac 9947?
The Generac 9947 is designed for use with compatible single-phase Generac standby generators that utilize Evolution™ or Power Zone™ 200 controls. Generator and transfer-switch compatibility should always be verified for the specific generator model before installation.
What does an automatic transfer switch do during a power outage?
An automatic transfer switch allows a standby generator system to automatically move designated electrical loads from utility power to generator power when an outage occurs. When utility power returns, the system transfers the loads back to the utility source. This allows the standby power system to operate without the homeowner manually switching power sources.
Why choose a 16-circuit transfer switch instead of a whole-house transfer switch?
A 16-circuit transfer switch is a good option when you only need to protect selected essential loads during an outage. Instead of sizing the backup system around every circuit in the home, you can prioritize equipment such as refrigeration, lighting, heating, pumps, internet equipment, and other critical loads. This can provide a practical backup solution when whole-house coverage is unnecessary.
What is the difference between the Generac 9947 and Generac 9935 100A transfer switches?
The biggest difference is the integrated load center. The Generac 9947 is a 100A automatic transfer switch with a 16-circuit load center, while the Generac 9935 is a 100A automatic transfer switch without the integrated 16-circuit essential-load center. The 9947 is therefore particularly useful when the goal is to create a dedicated group of circuits for generator backup.
Ideal Applications
The Generac 9947 is especially well suited for homes where the generator is intended to back up selected essential circuits rather than every electrical load in the house. It can be a strong choice for protecting refrigeration, lights, heating equipment, pumps, communications equipment, security systems, and other critical circuits during an outage.
