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Cummins 400 amp automatic transfer switch 240v | A050W853

$3,654.99
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#RA400 SE A050W853

The RA Automatic Transfer Switch is integrated with the RS series genset.  These products are Listed to UL 1008, the Standard for Transfer Switch Safety. The switch and generator set combination is specifically designed for a simplified, quicker installation. 

These UL 1008 switches are suitable for standby power systems in residential and light commercial applications. These RA products adhere to National Electrical Code (NEC) and National Fire Protection Association (NFPA) requirements.  

The RA transfer switch monitors utility power 24 hours a day and 7 days a week.  When utility power becomes unsatisfactory or fails; the generator set is signaled to start, then automatically transfers the load. When stable utility voltage returns, the transfer switch will automatically switch electrical load from the generator to the utility. No action is required by the home owner.  

(For Cummins Connect Series Generators Only)

Key features

Mechanically Interlocked Contractor

  • Long-life, high pressure, silver alloy contact resist burning and pitting
  • A powerful and economical solenoid drives the mechanism

UL 489 Listed Circuit Breaker

Solid Bus Bar Connection

  • Between circuit breaker and transfer switch

Neutral and Ground Bar

  • Bonding jumper on neutral and ground
  • Silver plated coper ground and neutral bus

Ease of Connection

  • Solderless screw type terminals for external power connections

Aluminum Enclosure

    • NEMA Type 3R rated

Specification

  • Current Rating: 400 Amp
  • Voltage Rating: 240 VAC
  • Number of Poles: 2
  • Enclosure Type: NEMA 3R
  • Enclosure Rating: NEMA 3R (Suitable for outdoor use, provides protection against rain, sleet, and ice)
  • Service Entrance Rated: Approved for use as a service entrance device, meeting applicable safety and regulatory standards.
  • Compatibility: Specifically designed for use with Cummins Connect Series Generators.

        Document Library

        Spec Sheet

        Outline Drawing

        Wiring Diagram

        Wiring Diagram,Interconnection

        Withstand and Closing Tables

        Shipping Policy

        Our goal is to get your parts and products to you as efficiently and safely as possible. The guidelines below outline what you can expect about fulfillment, shipping, and eligible products.

        Shipping and Order Fulfillment Guidelines


        Order Fulfillment: Orders usually ship within 1-5 business days. Shipments generally arrive in 1-3 business days after leaving our facilities. Please note that no orders will be fulfilled on Saturday or Sunday; instead, they will be fulfilled the next business day.



        Pick Up: You may choose to pick-up your order at no cost from any of our listed locations in the USA and Canada. As soon as the order is ready for pick-up, we will send you an email. Your order should be ready for pickup within 2 – 3 business days, depending on the availability of parts.



        Shipping Address: Your shipping address may be either a residential or commercial address in the United States and Canada. We do not ship to P.O. Box addresses, and we do not ship to any addresses outside the USA and Canada.



        Method of Shipping: Standard ground shipping is the default shipping method for the USA and Canada.* Once your product is shipped, it should take 1–3 business days for delivery. Standard shipping to Alaska and Hawaii typically takes 14–21 business days.

        * Exceptions may apply in shipping to some states in the USA. Currently, Build the Power does not offer shipping to US territories, Nunavut, Northwest Territories or Yukon.

         

        Shipping Fees

        Free Shipping: We offer free shipping on all orders.

         

        Eligible Products

        All products are eligible for Standard Free Shipping except for the product categories listed below. These products are eligible for Store Pick-Up Only:

        Dangerous or hazardous goods, such as batteries.
        Products that require special handling, such as a pail of oil or coolant.

        Returns and Refunds Policy

        We are committed to providing a straightforward, hassle-free return process. Please read our policy to be sure your order qualifies.

        If your product was damaged in shipping, or if you received an incorrect part please contact us so that we can assist you. Do not initiate a return for such orders.

        Return Guidelines

        Return Initiation

        Your return must be initiated on Build the Power website. Please do not take your parts to a store without initiating the return online first as your returns will not be accepted.


        Return Timeline

        Eligible part returns can be initiated for up to 30 days from the shipment or pickup availability date. Returns must be received by the return location within 14 days of return initiation.


        Return Method

        You may return products either in-store to your original pickup location, or through mail. Drop off returns are only available if you picked up your products at a branch.



        In-Store Return: Available only for pickup orders. You will need to initiate the return online first. Look up your order using your Order Number and email address and identify the product(s) you would like to return. You will then have the option to return the product(s) to your original pickup location. You will be issued a Return Confirmation email as soon as you submit your return request. Please bring a copy of the packing slip from your return order along with the products. Note: If you purchased as a signed in user, make sure to sign into your account first.


        Mail-In Return: You will need to initiate the return online first. Look up your order using your Order Number and email address and identify the product(s) you would like to return. You will be issued a Return Confirmation email as soon as you submit your return request. Include the packing slip with your parts that are being returned. 


        Product Condition

        Products purchased on buildthepower.com must be returned in saleable condition — in other words, unused, in the original packaging, and undamaged. Please note, all accepted returns will incur a 15% handling fee.


        Products that are Not Eligible for Return

        -Superseded and obsolete products or parts.
        -Parts that were not purchased through the Build the Power.
        -Parts not purchased from Build the Power and non-stocking parts.
        -Piston pins except as part of piston or cylinder kits.
        -Electronics (including but not limited to sensors)
        -Hazardous materials such as paints, sealants, flush kits, lubricants, spray cleaners and other materials.
        -Consumable products.
        -Software.
        -Make-to-Order and Customized items (calibrated fuel pumps, custom specified radiators / alternators / mufflers /adapters / etc.)
        -Belts, service tools, and rebuilt or non-genuine parts.
        -Printed circuit boards and other electronic components that were shipped in anti-static packaging which have been opened.


        Refund Policy

        Handling Fees

        All accepted parts returns will incur a 15% handling fee.


        Return Label

        You will be responsible for shipping the return package to the appropriate location. For US returns, we recommend you ship via FedEx to avoid potential delays. If you are returning a product because an incorrect part was shipped, or the product was damaged in shipping please contact us so that we can assist you.


        Refund Timeline

        Once we have approved the return, a refund will be issued within 7-10 business days.

        Warranty

        2 years factory warranty.

        Description
         

        #RA400 SE A050W853

        The RA Automatic Transfer Switch is integrated with the RS series genset.  These products are Listed to UL 1008, the Standard for Transfer Switch Safety. The switch and generator set combination is specifically designed for a simplified, quicker installation. 

        These UL 1008 switches are suitable for standby power systems in residential and light commercial applications. These RA products adhere to National Electrical Code (NEC) and National Fire Protection Association (NFPA) requirements.  

        The RA transfer switch monitors utility power 24 hours a day and 7 days a week.  When utility power becomes unsatisfactory or fails; the generator set is signaled to start, then automatically transfers the load. When stable utility voltage returns, the transfer switch will automatically switch electrical load from the generator to the utility. No action is required by the home owner.  

        (For Cummins Connect Series Generators Only)

        Key features

        Mechanically Interlocked Contractor

        • Long-life, high pressure, silver alloy contact resist burning and pitting
        • A powerful and economical solenoid drives the mechanism

        UL 489 Listed Circuit Breaker

        Solid Bus Bar Connection

        • Between circuit breaker and transfer switch

        Neutral and Ground Bar

        • Bonding jumper on neutral and ground
        • Silver plated coper ground and neutral bus

        Ease of Connection

        • Solderless screw type terminals for external power connections

        Aluminum Enclosure

          • NEMA Type 3R rated

        Specification

        • Current Rating: 400 Amp
        • Voltage Rating: 240 VAC
        • Number of Poles: 2
        • Enclosure Type: NEMA 3R
        • Enclosure Rating: NEMA 3R (Suitable for outdoor use, provides protection against rain, sleet, and ice)
        • Service Entrance Rated: Approved for use as a service entrance device, meeting applicable safety and regulatory standards.
        • Compatibility: Specifically designed for use with Cummins Connect Series Generators.

              Document Library

              Spec Sheet

              Outline Drawing

              Wiring Diagram

              Wiring Diagram,Interconnection

              Withstand and Closing Tables

              Shipping Policy

              Our goal is to get your parts and products to you as efficiently and safely as possible. The guidelines below outline what you can expect about fulfillment, shipping, and eligible products.

              Shipping and Order Fulfillment Guidelines


              Order Fulfillment: Orders usually ship within 1-5 business days. Shipments generally arrive in 1-3 business days after leaving our facilities. Please note that no orders will be fulfilled on Saturday or Sunday; instead, they will be fulfilled the next business day.



              Pick Up: You may choose to pick-up your order at no cost from any of our listed locations in the USA and Canada. As soon as the order is ready for pick-up, we will send you an email. Your order should be ready for pickup within 2 – 3 business days, depending on the availability of parts.



              Shipping Address: Your shipping address may be either a residential or commercial address in the United States and Canada. We do not ship to P.O. Box addresses, and we do not ship to any addresses outside the USA and Canada.



              Method of Shipping: Standard ground shipping is the default shipping method for the USA and Canada.* Once your product is shipped, it should take 1–3 business days for delivery. Standard shipping to Alaska and Hawaii typically takes 14–21 business days.

              * Exceptions may apply in shipping to some states in the USA. Currently, Build the Power does not offer shipping to US territories, Nunavut, Northwest Territories or Yukon.

               

              Shipping Fees

              Free Shipping: We offer free shipping on all orders.

               

              Eligible Products

              All products are eligible for Standard Free Shipping except for the product categories listed below. These products are eligible for Store Pick-Up Only:

              Dangerous or hazardous goods, such as batteries.
              Products that require special handling, such as a pail of oil or coolant.

              Returns and Refunds Policy

              We are committed to providing a straightforward, hassle-free return process. Please read our policy to be sure your order qualifies.

              If your product was damaged in shipping, or if you received an incorrect part please contact us so that we can assist you. Do not initiate a return for such orders.

              Return Guidelines

              Return Initiation

              Your return must be initiated on Build the Power website. Please do not take your parts to a store without initiating the return online first as your returns will not be accepted.


              Return Timeline

              Eligible part returns can be initiated for up to 30 days from the shipment or pickup availability date. Returns must be received by the return location within 14 days of return initiation.


              Return Method

              You may return products either in-store to your original pickup location, or through mail. Drop off returns are only available if you picked up your products at a branch.



              In-Store Return: Available only for pickup orders. You will need to initiate the return online first. Look up your order using your Order Number and email address and identify the product(s) you would like to return. You will then have the option to return the product(s) to your original pickup location. You will be issued a Return Confirmation email as soon as you submit your return request. Please bring a copy of the packing slip from your return order along with the products. Note: If you purchased as a signed in user, make sure to sign into your account first.


              Mail-In Return: You will need to initiate the return online first. Look up your order using your Order Number and email address and identify the product(s) you would like to return. You will be issued a Return Confirmation email as soon as you submit your return request. Include the packing slip with your parts that are being returned. 


              Product Condition

              Products purchased on buildthepower.com must be returned in saleable condition — in other words, unused, in the original packaging, and undamaged. Please note, all accepted returns will incur a 15% handling fee.


              Products that are Not Eligible for Return

              -Superseded and obsolete products or parts.
              -Parts that were not purchased through the Build the Power.
              -Parts not purchased from Build the Power and non-stocking parts.
              -Piston pins except as part of piston or cylinder kits.
              -Electronics (including but not limited to sensors)
              -Hazardous materials such as paints, sealants, flush kits, lubricants, spray cleaners and other materials.
              -Consumable products.
              -Software.
              -Make-to-Order and Customized items (calibrated fuel pumps, custom specified radiators / alternators / mufflers /adapters / etc.)
              -Belts, service tools, and rebuilt or non-genuine parts.
              -Printed circuit boards and other electronic components that were shipped in anti-static packaging which have been opened.


              Refund Policy

              Handling Fees

              All accepted parts returns will incur a 15% handling fee.


              Return Label

              You will be responsible for shipping the return package to the appropriate location. For US returns, we recommend you ship via FedEx to avoid potential delays. If you are returning a product because an incorrect part was shipped, or the product was damaged in shipping please contact us so that we can assist you.


              Refund Timeline

              Once we have approved the return, a refund will be issued within 7-10 business days.

              Warranty

              2 years factory warranty.

              what’s included
               

              The E2000LFP Expandable Power Station combines power and flexibility in a portable package. Link it with two EB3000 battery packs to reach an impressive 8064Wh capacity - enough for almost any power need.

              With 2000W AC output, it runs most household devices and tools without breaking a sweat. The advanced LiFePo4 batteries deliver outstanding durability, keeping 80% capacity even after 3500 charging cycles.

              Charging is quick and flexible. The station accepts up to 1300W input across multiple ports, with 600W maximum solar input. Using solar panels, you'll fully charge in 2-3 hours. Need it faster? Dual AC adapters cut that time to just 1.5-2 hours.

              Specification
               

              The E2000LFP Expandable Power Station combines power and flexibility in a portable package. Link it with two EB3000 battery packs to reach an impressive 8064Wh capacity - enough for almost any power need.

              With 2000W AC output, it runs most household devices and tools without breaking a sweat. The advanced LiFePo4 batteries deliver outstanding durability, keeping 80% capacity even after 3500 charging cycles.

              Charging is quick and flexible. The station accepts up to 1300W input across multiple ports, with 600W maximum solar input. Using solar panels, you'll fully charge in 2-3 hours. Need it faster? Dual AC adapters cut that time to just 1.5-2 hours.

              Shipping & Delivery
               

              The E2000LFP Expandable Power Station combines power and flexibility in a portable package. Link it with two EB3000 battery packs to reach an impressive 8064Wh capacity - enough for almost any power need.

              With 2000W AC output, it runs most household devices and tools without breaking a sweat. The advanced LiFePo4 batteries deliver outstanding durability, keeping 80% capacity even after 3500 charging cycles.

              Charging is quick and flexible. The station accepts up to 1300W input across multiple ports, with 600W maximum solar input. Using solar panels, you'll fully charge in 2-3 hours. Need it faster? Dual AC adapters cut that time to just 1.5-2 hours.

              Top Solar and Generator Brands

              Free U.S. Shipping

              30-Day Returns

              Expert Support Team

              Get Started In 3 Simple Steps

              The whole process is easy – no salespeople involved.

              Step 1: Choose Your System

              Pick your products at direct-to-you prices. Browse complete systems and see exactly what you'll pay.

              Step 2: Place Your Order

              Quick online checkout with free U.S. shipping. Your order ships within 3-5 business days.

              Step 3: Power Up

              Professional guidance for setup and connection. Our team helps you get the most from your power station.

              The Build The Power Difference

              Here’s why you’ll prefer us over other providers.

              OTHER PROVIDERS
              Straightforward Online Pricing
              No Pushy Sales Tactics
              Expert Technical Support
              24/7 Digital Ordering
              Clear Installation Steps
              No Hidden Costs or Fees

              What Our Customers Say

              Direct experiences from homeowners who took control of their energy costs.

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              - John S.

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              - John S.

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              - John S.

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              - John S.

              Frequently Asked Questions

              How is Build The Power different from other companies?
               

              Unlike traditional companies, we've removed the complex network of salespeople, project managers, and dealer fees. You browse and buy directly through our digital platform, cutting costs by 20-50% while still getting expert support when you need it.

              How does your ordering process work?
               

              Browse & Select – Find the product that suits your needs.Add to Cart – Click "Add to Cart" and proceed to checkout. Secure Payment – Complete your purchase using our secure payment options. Order Confirmation – You’ll receive an email confirmation with your order details. Shipping & Delivery – We process and ship your order as quickly as possible. A tracking number will be provided. If you have any questions, feel free to contact us!

              Do you offer free shipping?
               

              Yes! We offer free shipping on all orders, with no minimum purchase required. Enjoy hassle-free shopping without worrying about extra shipping costs. Once your order is processed, we’ll provide a tracking number so you can follow your shipment’s progress.

              What's your return policy?
               

              We offer a 30-day return policy for your peace of mind. If you're not completely satisfied with your purchase, you can return it within 30 days of delivery for a refund or exchange. The item must be in its original condition and packaging.

              To start a return, contact our support team, and we’ll guide you through the process.

              Can I get help with installation?
               

              We do not offer installation services, but we’re happy to recommend trusted companies or services that can assist you. If you need help finding an installer, feel free to contact us, and we’ll point you in the right direction!

              Top Solar and Generator Brands

              Free U.S. Shipping

              30-Day Returns

              Expert Support Team

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