Generac Guardian 11kW Standby Generator Pre Packaged with 50 Amp 12 Circuit ATS 6437
Generac Power Systems

The 6437 standby generator from Generac includes the 50-ampere automatic transfer switch with load center. When a storm or other event interrupts utility power, the generator and transfer switch operate automatically to supply your home with up to 11 kilowatts of backup emergency power, to protect your home and family from unexpected power outages.

Fuel Choices

The 6437 standby generator is factory ready for Natural Gas, but easily and quickly converts to LP gas (propane) during installation. LP gas allows the generator to produce a full 11 kilowatts of power, and 10 kilowatts using natural gas. At half load, the generator uses 1.2 gallons of LP gas or 124 cubic feet of natural gas. Actual fuel consumption is directly related to the electrical load which changes continuously.


The GH-530 is an 18-horsepower, overhead-valve industrial engine designed specifically by Generac for use in its generators. The electronic ignition engine runs at constant 3600 RPM for clean, smooth electrical output from the generating unit. Features like 'Spiny-Lok' cast iron cylinder walls for extra rigidity, a pressurized lubrication system, and a 200 hour-2 year maintenance schedule allow for extended operation during long-term outages with minimal maintenance and exceptional reliability.

Evolution Controller

The Evolution Controller handles most generator functions, including starting, stopping, and exercising the generator. It senses a power outage, starts the generator and signals the transfer switch to switch the house onto standby generator power. While the generator is operating, the Evolution monitors the voltage level and frequency and adjusts it to maintain utility-quality power. Once power is restored and the house is moved back onto utility power, it allows the generator engine to run during a cool-down period and then shuts it down.

Features include a programmable exercise period that keeps the generator lubricated and ready to run, advanced fault detection and reporting, and a dealer programmable start delay (2 to 1500 seconds) that guards against starting during momentary power interruptions. The controller includes a smart battery charger and alerts the homeowner to failing battery conditions. The color-coded membrane keypad and high-visibility LED indicators make using the controller easier than ever before.

The optional Mobile Link system keeps you connected to the generator wherever you go with text message alerts to your cell phone and access via laptop, smart phone, or tablet to the controller through a web-based dashboard where you can check on maintenance, get generator status, and other controller functions.

The basic wireless controller (optional) keeps you informed of generator status from inside your home, while the advanced model allows you to view alerts, status, and test the generator or program exercise periods.

Automatic Transfer Switch

The included automatic transfer switch is a pre-wired, 50 amp transfer switch and load center with 12 circuit breaker positions. Included are five 120-volt, 15-amp circuits, three 120-volt, 20-amp circuits, one 240-volt 30 amp, and one 240-volt 40 amp circuit. 240-volt circuits use two positions each.

The automatic transfer switch has two pre-wired conduits, one to connect directly to the main service panel and the other to the standby generator, greatly simplifying wiring and installation.

When utility power is interrupted, the transfer switch receives a signal from the Evolution Controller and switches the load center from utility power to generator power to supply your selected critical circuits with power until utility power is restored.

Generator Unit

The power generating unit utilizes a brush-less design that incorporates a revolving magnetic field and skewed stators. Brush-less technology improves reliability and extends the life of the generating unit. The revolving field and skewed stators provide better power regulation and a higher surge capacity for starting air conditioners and other large motors, even when the generator is under a continuously changing load.

Appearance and Noise

An all metal, steel enclosure with powder coat paint keeps the unit looking good, in all environments. The lockable hinged lid provides easy access to the controller and engine maintenance. At just 63db, the 6437 is quieter than many air conditioners and with the 48-inch-wide 25-inch-deep and 29-inch-high footprint, it fits into any neighborhood setting.

Country Living
Comment by Jim C. on 9th Nov 2014

My Mom and Dad are both in their 80's and live in the country. With the installation of the 6551 I can rest assured that they will never be without power, heat, ac and water. this is a great unit and worked perfectly upon startup. Should have installed this a lot sooner for them.

By the way, my son-in-law also has one for his home. I live in a motorhome or I would have one also.

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