
Cummins RA400 400A Service-Entrance Automatic Transfer Switch
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At a glance
- Amperage
- 400 A continuous
- Poles
- 2-pole
- Voltage
- 120/240 VAC
- Phase / Frequency
- Single phase, 60 Hz
- Service Entrance Rated
- Yes (UL 489 listed circuit breaker)
- Withstand/Closing Rating (WCR)
- 35 kA at 240 VAC and below
- Enclosure
- NEMA Type 3R, aluminum (indoor/outdoor)
- Dimensions (H x W x D)
- 48 in x 23.4 in x 10.5 in (1220 x 594 x 267 mm)
- Weight
- 95.6 lb (43.4 kg)
- Transfer Time
- Will not exceed 100 ms (source-to-source)
- Listings
- UL 1008 and CSA C22.5 No. 178.1
- Warranty
- 2-Year Limited (parts & labor)
Why this generator
- Service-entrance-rated 400-amp automatic transfer switch with an integrated UL 489 listed circuit breaker, eliminating the need for a separate service disconnect
- Dual-certified to UL 1008 and CSA C22.5 No. 178.1 for transfer switch safety, with a robust 35 kA short-circuit withstand and closing rating at 240 VAC
- Purpose-built to pair with Cummins Quiet Connect RS-series home standby generators (RS13A through RS50) for a simplified, faster outdoor installation
- Weatherproof NEMA Type 3R aluminum enclosure with a secure front for protection from the elements and vandals
- Monitors utility power 24/7 and automatically transfers the whole-home load to generator power and back, with no homeowner action required and fast sub-100 ms transfer
- Mechanically and electrically interlocked, break-before-make contactor with long-life silver-alloy contacts that resist burning and pitting; backed by a 2-year parts-and-labor warranty
Everything you need to know
400A, 240Vac, 2-Pole, NEMA 3R enclosure, CSA, Service Entrance Rated. (For Cummins Connect Series Generators Only)
Highlights
- Factory-authorized Cummins dealer
- MAP pricing — no hidden markup
- Whole-home standby coverage
- Expert sizing & installation available across NC & SC
Part Number: A066W927
Ships via calculated freight — shipping shown at checkout (heavy/hazmat item).
Frequently asked questions
Is this a genuine OEM part?+
Yes — sold and shipped as a genuine Cummins part from a factory-authorized dealer.
Will it fit my unit?+
Check your model and year — message us with that info and we'll confirm fit before you order.
How fast does it ship?+
Shipping is calculated at checkout (batteries, transfer switches and oversized items). Most leave the warehouse in 2–4 business days.
What's the return policy?+
30-day returns on unused parts and accessories in original packaging.
Fast nationwide shipping
Shipping calculated at checkout. Most items leave the warehouse in 2–4 business days.
Install help, no upsell
We size, spec, and connect you with a vetted local installer — or talk your contractor through it for free.
Genuine Cummins part
Sold and shipped as a genuine Cummins OEM part from a factory-authorized dealer. 30-day returns on unused parts in original packaging.