Model#: BGSN40517

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Brand new items;Full manufacturer warranty available
Manufacturer inspected, repaired and tested items; CPO 120 day money back guarantee
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New items with possible minor cosmetic damage; CPO 120 day money back guarantee
Returned items inspected, repaired and tested by CPO technicians; CPO 60 day money back guarantee

Briggs & Stratton 40517 12kW Auto Standby Generator

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Freight Orders

Freight deliveries require a delivery time be scheduled and someone must be present at the time of delivery to inspect and sign for the merchandise. A representative from the freight carrier will call the phone number entered at checkout to schedule the delivery.

Liftgate Service

For freight deliveries, you have the option of adding a liftgate to your delivery. A liftgate is the device that lowers a product from the truck to ground level.

CPO recommends adding liftgate service for freight deliveries exceeding 100 lbs if you do not have a loading dock or fork lift at the delivery address. Additional charges may apply. The liftgate option will be presented during the checkout process.

Please note that liftgate service only ensures the product is removed from the truck. We recommend you have the additional help of two to four people to move the product to its desired location because drivers are not required to assist.

Requesting liftgate service after ordering may result in additional charges and delays.

Ships in 2-3 business days

Product Overview


This Briggs & Stratton standby generator protects your home and family with affordable, reliable Briggs & Stratton backup power. This generator is 50% smaller and 60% quieter than their previous model. Its streamlined design meets the power needs of your whole house, with a more compact, affordable unit. This home standby generator includes outdoor/indoor NEMA 3R rated automatic transfer switch for easy installation. You can truly power more for less with this little powerhouse.
  • Streamlined compact design is 50% smaller than previous 12kW generators and is quieter by 4 decibels
  • Automatically powers your home in seconds after sensing a power outage
  • Commercial-grade Vanguard engines are designed and engineered to provide long-lasting, reliable power to give customers permanent protection
  • Designed to weather the elements, the system's enclosure is made from automotive-grade Galvanneal steel to resist rust
  • Advanced powder-coat paint process results in years of protection against chips and abrasions
  • More service access to the engine and alternator plus a user-friendly control panel makes repairs easier and less costly
  • Tested to start down at-20 deg. F, you can count on the generator to start on the coldest of winter days and deliver the power you rely on during a power outage
  • Thermostatically controlled battery warmer and oil heaters activate as the temperature drops increasing battery temperature for the engine to start
  • 12kW Auto Standby Generator - 40517
Compliance and Restrictions
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Length: 28 in.
Width: 26 in.
Height: 37.2 in.
Weight: 318 lbs.
Alternator Type: Brushless
Amperage (LP Vapor): 50A
Amperage (Natural Gas): 41.7A
Cooling System: Air-Cooled
Enclosure Type: Galvanneal
Engine Displacement: 627cc
Engine Make: Briggs & Stratton
Engine Model: Vanguard
Engine Speed (RPM): 3,600
Fuel Consumption at 100% Load (LP Vapor): 2.3 gal/hr.
Fuel Consumption at 100% Load (Natural Gas): 172 cu-ft./hr.
Fuel Consumption at 50% Load (LP Vapor): 1.7 gal/hr
Fuel Consumption at 50% Load (Natural Gas): 117 cu-ft./hr.
Fuel Type: Gas / Liquid Propane
Motor Phase: 1
Rated Watts (LP Vapor): 12kW
Rated Watts (Natural Gas): 10kW
Transfer Switch Circuits: Whole House
Transfer Switch Included: No
Transfer Switch Voltage: 120V / 240V
Voltage: 120V/240V
Voltage Regulation: Automatic



5.0 / 5.0
10 Reviews
5 Stars
4 Stars
3 Stars
2 Stars
1 Star
Yes, I would recommend this to a friend (1)
Bought January 2017
I bought this in January 2017, one month later my electric was off for 12 hours. I am so glad I invested in this product. I went with this company because of the name brand and also the 6 year warranty. I'm an elderly woman and can't fix things myself so the warranty was important to me, along with the ease of getting parts if needed. I previously had a portable generator which was a pain to get going and hook up, plus it wasn't large enough to run the heat pump. After the recent loss of power, I had the installer come the next day to change the oil and filter since the manual states to change after 5 hours of run time. So far so good! I had been wanting a generator for a number of years. The power goes off frequently anymore because of the craziness of the weather. It wasn't like this when I was young.
March 8, 2017
Originally posted at
Physical Size, Quiet, Reliable
Bought this unit in October 2016... Tech support and knowledge of product from Briggs is unsurpassed.... Generator is extremely quiet, powers my house very nicely, easy to wire, and very compact.... Love it, but more than that, the tech support is supreme.....
December 14, 2016
Originally posted at
Great generator
I bought this generator 3 years ago and very happy with it. Never had a problem with it and runs like a charm. Langworthy Electrical was fantastic and couldn't be more happier with there service and being so loyal to there customers.
March 31, 2016
Originally posted at
great generator
I have a 12000 kw briggs standby generator that runs on propane, with a 200 amp transfer switch. the greatest investment I have ever done.
May 1, 2014
Originally posted at
My 12kw 16 circuit 100 amp generator
Ibought this 9 months ago and after many installation problems I am very glad I made this purchase.
March 15, 2014
Originally posted at
Great Whole house Generator
Recently installed and actually went on a month later during power outage. Fabulous especially after being out of power during hurricane Sandy for 15 days. You can not fathom our family's joy at having power
March 15, 2014
Originally posted at
12 kw standby generator
This generator has been sitting outside in Vermont, snow, rain, ice storms in a town where a power outage is a weekly event, not to mention the annual Thanksgiving extended power fai- lure. With only minimal yearly maintenance, it's always functioned perfectly. We're frequently the only house on the street with lights and heat. It also powers central A/C, electric cooking and a dryer. I should have installed it years earlier, and only wish I'd gotten the 15kw system for quieter variable operation.
March 14, 2014
Originally posted at
my 12 kw generator with 200 amp ats has been in use for 3 yrs now with no problems.
March 8, 2014
Originally posted at
Highly recommend this generator
Had this unit professionally installed . Worked like a charm during SANDY. A little noisy outside but I expected this from a 29 HP engine. I plan on enclosing the unit with a fence which should quiet it a bit outside. I had four estimates and all four favored B+S products. Do yourself a favor and have this professionaly installed. Do not try to do this yourself unless you are a licensed electrician and plumber.
October 31, 2012
Originally posted at
Yes, I would recommend this to a friend
Highly recommend this generator
Had this unit professionally installed . Worked like a charm during SANDY. A little noisy outside but I expected this from a 29 HP engine. I plan on enclosing the unit with a fence which should quiet it a bit outside. I had four estimates and all four favored B+S products. Do yourself a favor and have this professionaly installed. Do not try to do this yourself unless you are a licensed electrician and plumber.
October 31, 2012

Questions & Answers

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Browse 3 questions Browse 3 questions and 2 answers
Any ideas on LP consuming per day on the 12 KW?
A shopper on Oct 16, 2017
The overview says it comes with a transfer switch but the specifications says it does not come with one
Can you clarify if it does and if it does what type does it come with ?
A shopper on Mar 3, 2019
BEST ANSWER: Model 40517 does not include the transfer switch.
WHAT IS THE dB noise level at 7 meter?
E the great on Sep 7, 2017
BEST ANSWER: approximately 69 dB


Briggs and Stratton Portable Generator Limited Warranty

Briggs and Stratton Power Products Group, LLC will repair or replace, free of charge, any part(s) of the portable generator that is defective in material or workmanship or both. Transportation charges on product submitted for repair or replacement under this warranty must be borne by purchaser. This warranty is effective for the time periods and subject to the conditions stated below. For warranty service, find the nearest Authorized Service Dealer in the dealer locator map at

THERE IS NO OTHER EXPRESS WARRANTY. IMPLIED WARRANTIES, INCLUDING THOSE OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, ARE LIMITED TO ONE YEAR FROM PURCHASE, OR TO THE EXTENT PERMITTED BY LAW. ANY AND ALL IMPLIED WARRANTIES ARE EXCLUDED. LIABILITY FOR INCIDENTAL OR CONSEQUENTIAL DAMAGES ARE EXCLUDED TO THE EXTENT EXCLUSION IS PERMITTED BY LAW. Some states or countries do not allow limitations on how long an implied warranty lasts, and some states or countries do not allow the exclusion or limitation of incidental or consequential damages, so the above limitation and exclusion may not apply to you. This warranty gives you specific legal rights and you may also have other rights which vary from state to state or country to country.


  • Consumer Use - 2 Years* (*2nd Year Parts Only)
  • Commercial Use - 1 Years

The warranty period begins on the date of purchase by the retail consumer or commercial end user, and continues for the period of time stated above. "Consumer use" means personal residential household use by a retail consumer. "Commercial use" means all other uses, including use for commercial, income producing or rental purposes. Once equipment has experienced commercial use, it shall thereafter be considered as commercial use for purpose of this warranty.



We welcome warranty repair and apologize to you for being inconvenienced. Any Authorized Service Dealer may perform warranty repairs. Most warranty repairs are handled routinely, but sometimes requests for warranty service may not be appropriate. For example, warranty service would not apply if equipment damage occurred because of misuse, lack of routine maintenance, shipping, handling, warehousing or improper installation, Similarly, the warranty is void if the manufacturing date or serial number on the portable generator has been removed or the equipment has been altered or modified. During warranty period, the Authorized Service Dealer, at it's option, will repair or replace any part that, upon examination, is found to be defective under normal use and service. This warranty will not cover the following:

  • NORMAL WEAR: Outdoor Power Equipment, like all mechanical devices, needs periodic parts and service to perform well. This warranty does not cover repair when normal use has exhausted the life of a part or the equipment.
  • INSTALLATION AND MAINTENANCE: This warranty does not apply to equipment or parts that have been subjected to improper or unauthorized installation or alteration and modification, misuse, negligence, accident, overloading, overspeeding, improper maintenance, repair or storage so as, in out judgement, to adversely affect its performance and reliability. This warranty also does not cover normal maintenance such as filters, adjustments, fuel system cleaning and obstruction (due to chemical, lime, dirt, and so forth).
  • OTHER EXCLUSIONS: This warranty excludes wear items such as o-rings, filters, etc., or damage or malfunctions resulting from accidents, abuse, modifications, alterations, or improper servicing or freezing or chemical deterioration. Accessory parts, such as starting batteries, generator adapters cord sets and storage covers are excluded from the product warranty. This warranty excludes used, reconditioned and demonstration equipment and failures due to acts of God and other force majeure beyond the manufacturers control.