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Generac 400 Amp Smart Transfer Switch 120/240V NEMA 3R
- $1,295.00
- Brands Generac
- Product Code: RTSW400A3
- Availability: In Stock
Generac 400 Amp Service Rated 120/240-Volt Single-Phase NEMA 3R Smart Transfer SwitchThe Generac 400 Amp Service Rated 120/240-Volt Single-Phase NEMA 3R Smart Transfer Switch is a high-capacity automatic transfer switch designed to connect compatible single-phase standby generators to a home's or facility's electrical system during a utility power interruption.Rated for 400 amps, this service-entr..
Reliable Generac 400 Amp Transfer Switch for Single Phase Power Systems
Generac 400 Amp Service Rated 120/240-Volt Single-Phase NEMA 3R Smart Transfer Switch
The Generac 400 Amp Service Rated 120/240-Volt Single-Phase NEMA 3R Smart Transfer Switch is a high-capacity automatic transfer switch designed to connect compatible single-phase standby generators to a home's or facility's electrical system during a utility power interruption.
Rated for 400 amps, this service-entrance-rated transfer switch is designed for larger electrical services where a higher-capacity automatic transfer solution is required. Its NEMA 3R aluminum enclosure is suitable for indoor or outdoor installation and helps protect the switch from rain, snow, ice, and debris.
The integrated load-management system can manage up to four individual HVAC loads without additional hardware, helping users prioritize available generator capacity during an outage.
Key Features
400-amp rated capacity for high-demand electrical services.
120/240-volt, single-phase configuration.
Service entrance rated for applications requiring a service-rated transfer switch.
Automatic transfer operation for compatible standby generator systems.
NEMA 3R aluminum enclosure for indoor or outdoor installation.
Heavy-duty Generac contactor designed for long-term service.
Integrated Smart A/C Module (SACM) for load management.
Can manage up to four individual HVAC loads without additional accessories.
Additional load-management capability is available when paired with compatible Smart Management Modules.
Designed for use with compatible Generac single-phase standby generators.
Backed by a 5-year limited warranty according to Generac's current product information.
Automatic Transfer Operation
The transfer switch is designed to automatically move the electrical load between utility power and a compatible standby generator.
When utility power is interrupted, the compatible Generac generator's controller handles the necessary sensing, timing, exercising, and transfer commands. Once generator power is available and the transfer sequence is completed, the transfer switch connects the designated electrical system to generator power.
When utility power returns, the system automatically transfers the load back to the utility according to the generator system's programmed sequence.
This automatic operation helps provide continuity of power without requiring the user to manually switch the electrical supply during an outage.
400-Amp Service Capacity
With a 400-amp rating, this transfer switch is designed for larger electrical services than standard 100- or 200-amp residential transfer switches.
The high-capacity design makes it appropriate for applications where the electrical service requires a 400-amp transfer device. The actual generator size and connected electrical load must still be properly matched; a 400-amp transfer switch does not mean that a generator can supply 400 amps continuously.
A qualified electrical professional should determine the appropriate generator size, conductor sizing, overcurrent protection, and installation configuration.
Service Entrance Rated
The service-entrance-rated configuration allows the transfer switch to serve as part of the service equipment arrangement where permitted by the applicable electrical installation requirements.
Generac describes the service entrance disconnect as a device that allows the electrical service to be interrupted and manually disconnected from utility power.
Because service equipment is part of the building's primary electrical distribution system, installation should be performed by a qualified electrician in accordance with applicable electrical codes and the manufacturer's installation instructions.
NEMA 3R Outdoor Enclosure
The transfer switch uses an aluminum NEMA Type 3R enclosure designed for indoor or outdoor installation.
The enclosure is intended to protect the internal components from common outdoor environmental conditions, including:
Rain
Snow
Ice
Debris
Generac also specifies an electrostatically applied and baked powder-coated finish for its service-rated enclosure.
Proper installation is still required to maintain the enclosure's intended protection.
Intelligent Load Management
One of the key advantages of this transfer switch is its integrated Smart A/C Module (SACM).
The system can manage up to four individual HVAC loads controlled by 24 VAC thermostatic signals without requiring additional load-management hardware.
When additional compatible Smart Management Modules are used, Generac indicates that further loads can be managed. This can help optimize generator capacity and reduce the likelihood of excessive electrical demand during backup operation.
Heavy-Duty Contactor
The transfer switch uses a heavy-duty Generac contactor designed for repeated transfer operation.
Generac identifies the contactor as an ETL-recognized device intended for long-term service.
This component is responsible for switching the electrical connection between utility and generator power as directed by the generator system's control logic.
Compatible Generator Systems
This transfer switch is designed for use with compatible single-phase Generac standby generators.
Compatibility should always be verified using the exact generator model and transfer-switch model before installation. Electrical ratings, controller compatibility, service configuration, and installation requirements must all be considered.
Product Specifications
| Specification | Details |
|---|---|
| Brand | Generac |
| Product Type | Automatic Transfer Switch |
| Rated Amperage | 400 A |
| Voltage | 120/240 V |
| Phase | Single Phase |
| Transfer Method | Automatic |
| Service Rating | Service Entrance Rated |
| Enclosure | NEMA Type 3R |
| Enclosure Material | Aluminum |
| Generator Compatibility | Compatible Generac Single-Phase Standby Generators |
| Load Management | Integrated Smart A/C Module (SACM) |
| HVAC Loads Managed | Up to 4 individual HVAC loads |
| Contactor | Heavy-Duty Generac Contactor |
| Installation | Indoor or Outdoor |
| Warranty | 5-Year Limited Warranty |
Specifications above are based on Generac's official product page and technical documentation for the 400A service-rated model.
Benefits at a Glance
400-Amp Capacity
Provides a high-capacity transfer solution for electrical services requiring a 400-amp rating.
Automatic Operation
Automatically transfers compatible electrical loads between utility and standby generator power.
Service Entrance Rated
Designed for applications where service-rated transfer equipment is required.
NEMA 3R Enclosure
The aluminum outdoor-rated enclosure helps protect internal components from rain, snow, ice, and debris.
Integrated Load Management
The built-in Smart A/C Module can manage up to four individual HVAC loads without additional load-management hardware.
Heavy-Duty Construction
A Generac heavy-duty contactor is designed to support reliable transfer operation over extended service.
Installation Considerations
A 400-amp service-rated transfer switch is a major component of an electrical service installation. Installation should be performed by a qualified electrician familiar with standby-generator systems and applicable electrical codes.
Before installation, confirm:
Generator and transfer-switch compatibility.
Available electrical service capacity.
Required conductor and conduit sizes.
Service-disconnect requirements.
Grounding and bonding requirements.
Local electrical-code requirements.
Required clearances and mounting location.
Proper load-management configuration.
The enclosure's NEMA 3R rating does not eliminate the need for correct mounting, wiring, grounding, and environmental installation practices.
Built for High-Capacity Standby Power
The Generac 400 Amp Service Rated 120/240-Volt Single-Phase NEMA 3R Smart Transfer Switch is designed for high-capacity automatic standby-power installations where reliable transfer and intelligent load management are important.
Its combination of 400-amp service-rated capacity, 120/240-volt single-phase operation, NEMA 3R aluminum construction, automatic transfer functionality, heavy-duty contactor, and integrated Smart A/C Module makes it a strong choice for compatible Generac standby-generator systems requiring a high-capacity transfer solution.