Generac Protector Series 20kW Automatic Standby Diesel Generator RD02023
Generac Power Systems

Generac Protector Series 20kW Automatic Standby Diesel Generator

Standby diesel power comes to homes and small businesses with the Protector Series from Generac Power Systems. The RD02023 is a 20 kilowatt standby generator that automatically supplies power during an outage to keep essentials and conveniences like refrigerators, air conditioners, pumps, and furnaces running. The generator and automatic transfer switch (sold separately) are a permanently installed system that connect directly to the home or business electrical system. The Protector Series of Standby Generators have a 5-year limited manufacturer's warranty.

Ships factory direct: single phase option allow approximately 3-4 weeks, and 3 phase options allow appoximately 5-6 weeks.

Code Ready

Meeting local building codes and ordinances is no longer a problem with Generac's Code-Ready Accessories, options that eliminate custom configurations and additions. Fuel-tank risers, spill collectors, lockable fuel caps, and low-fuel alarms are just a few of the options available to help you meet local codes without worry. Even when code requirements vary from one locality to another, your Protector Series Generator easily conforms by choosing from Code Ready Accessories.

The fuel tank is a UL/CUL-142 listed double-walled tank with external venting, filling, and leak detection. The double-wall design contains leaks within the secondary tank, preventing contamination of the surrounding environment. An alarm is issued in the event of a leak and the unit is shut down.


Generac equips the RD02023 standby generator with their own 2.28 liter, inline four-cylinder diesel engine. The power plant features cast-iron cylinder heads, overhead valves, and aluminum pistons for efficient performance and a long, trouble-free life.

Engine sensors for low oil pressure, high engine and high oil temperature, and overspeed/overcrank conditions allow shutdown to prevent engine damage. The engine is liquid cooled with a radiator, fan and coolant pump similar to automotive engines.

At full load, the engine consumes 2 gallons of diesel per hour. The 34-gallon, integrated-base fuel tank will keep the engine running at half-load for more than 28 hours.

Evolution Controls

Generac's Evolution Controller is the heart of this standby generator system. It monitors utility power 24 hours a day and detects outages immediately. If utility power is lost, the controller waits two to 1500 seconds (dealer programmable) and then starts the engine. The delay eliminates false starts during momentary outages. Once engine speed stabilizes, the controller signals the automatic transfer switch to supply the building with generator power and isolate the building from the electric utility.

When the controller detects a stable utility supply, it instructs the transfer switch to disconnect the generator and reconnect the utility supply. It allows the engine to operate for a minute during a cool-down cycle and then shuts it down.

A multi-lingual display provides reports, status, programmable functions, and alerts and is accessed through a membrane keypad backlit with colored LEDs.

Other functions include monitoring engine sensors, voltage and frequency regulation, programmable weekly exercise periods, maintenance and status alerts, and extensive fault reporting. An integrated smart battery charger alerts the owner to replace the battery before it can no longer retain a charge.

Controller access via a web-based dashboard is provided by the optional Mobile Link accessory and allows access from inside the building or across the country via smart phone, tablet, or computer browser. Check system status, schedule maintenance, view reports, or program exercise periods. Mobile Link can also send text message alerts to most regular cell phones.

Other wireless options include the Basic and Advanced Wireless Monitors. The basic unit allows viewing generator status from indoors, while the advanced model allows access to the controller display and functions.

Generator Unit

The heavy-duty, revolving-field generator unit is directly connected to the engine. The advanced voltage regulation and frequency control allow the generator to supply utility-grade power suitable for everything from sensitive electronics to heavy-duty motors. Even under heavy loads, the generator supplies clean power without electronic noise.

Appearance and Noise

An eye-pleasing design makes for a neighborhood friendly installation. At 81 inches wide, 50 inches high, and 31 inches deep, the aluminum enclosure sits on top of the integrated-base fuel tank. Viewing the controller display and main breaker positions has never been easier with a conveniently positioned viewing window.

The muffler is contained inside the cabinet to prevent injury and keeps noise to just 70dB, similar to most central air conditioners. Installation requires a concrete slab five feet or more from the building, depending on local building codes.

Compatible with Generac RTSW, RTSC, RTSR, RTSY, RTSN automatic transfer switches, options available for all phases and voltages.

Not for sale outside of US/CA
Meets EPA Emission Regulations
CA/MA Emissions Compliant

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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