Overview#
The Generac SD050 is a 50-kilowatt industrial diesel standby generator powered by Generac's 3.4-liter turbocharged and aftercooled inline-four engine. Rated at 50 kW standby and 45 kW prime, the SD050 represents the maximum output of Generac's 3.4L engine platform. EPA Certified for Stationary Emergency applications, it is available in single-phase and three-phase configurations across voltages from 120/240V through 346/600V.
The SD050 uses a Generac K0050124Y21 alternator with Class H insulation, synchronous brushless excitation, and a digital voltage regulator. The Digital H control panel provides NFPA 110 Level I and II programmable operation, Modbus communications, and predictive maintenance algorithms. A 120 VAC engine coolant heater is standard equipment, and a closed coolant recovery system is factory-installed.
At 50 kW, this unit serves mid-size commercial facilities with more substantial emergency load requirements: large restaurants, multi-tenant retail, medical suites, and small data rooms. The single-phase 120/240V configuration at 208 amps is practical for larger facilities with single-phase service; three-phase configurations at 75 amps (277/480V) cover facilities with three-phase distribution.
Technical Specifications#
| Parameter | Value |
|---|---|
| Standby Rating | 50 kW / 63 kVA |
| Prime Rating | 45 kW / 56 kVA |
| Engine Make | Generac |
| Displacement | 3.4 L (207.48 in³) |
| Cylinders | 4, In-Line |
| Bore x Stroke | 3.86 x 4.45 in (98 x 113 mm) |
| Compression Ratio | 18.5:1 |
| Aspiration | Turbocharged/Aftercooled |
| Engine Speed | 1,800 RPM |
| Alternator Model | K0050124Y21 |
| Insulation Class | H |
| Fuel Type | Ultra Low Sulfur Diesel #2 |
| Fuel Consumption (100%) | 4.3 gph |
| Fuel Consumption (75%) | 3.3 gph |
| Fuel Consumption (50%) | 2.3 gph |
| Fuel Consumption (25%) | 1.3 gph |
| Exhaust Flow | 448 cfm at rated output |
| Exhaust Temperature | 1,044°F (562°C) |
| Heat Rejection to Coolant | 135,900 BTU/hr |
| Combustion Air | 166 cfm |
| Open Set (no tank) L x W x H | 76.7 x 37.4 x 45.2 in |
| Open Set Dry Weight | 1,710 -- 1,836 lbs |
| Max Ambient Temperature | 122°F (50°C) |
Our Service Experience#
The SD050 is one of the most commonly specified 50 kW commercial diesel generators in our Northern California service territory. At 4.3 gph full-load fuel consumption, a standard 300-gallon sub-base tank provides approximately 69 hours of runtime -- adequate for most utility outage scenarios without refueling.
The 1,044°F exhaust temperature of the SD050 is the highest in the 3.4L family and demands careful attention to exhaust system routing. We have seen premature exhaust flex connector failures on installations where the unit is run at high load in poorly ventilated enclosures. Specify the Critical Grade Silencer for enclosed installations, and verify exhaust flex connector integrity at each service interval. The Bosch VE injection pump should receive clean diesel: maintain a fuel polishing schedule for any installation where the generator exercises less than monthly.
Frequently Asked Questions#
How does the SD050 compare to the SD060? The SD050 uses Generac's 3.4L engine while the SD060 transitions to the Iveco/FPT 4.5L inline-4. The SD060 produces 10 kW more standby output, has a lower exhaust temperature (930°F vs 1,044°F), and uses a physically larger package (92.9 x 40.0 x 49.2 in open set vs 76.7 x 37.4 x 45.2 in). For applications where 50 kW is marginally sufficient, the SD060 provides headroom without a major footprint increase.
Is the SD050 suitable for healthcare applications? Yes. The SD050 with NFPA 110 Level I programmable control is appropriate for non-critical healthcare loads where code requires generator-backed emergency power. For life-safety healthcare applications (operating rooms, ICU, life support), verify AHJ requirements for NFPA 99 and NFPA 110 compliance with the project electrical engineer.
What alternator upsizing options are available? The SD050 can be ordered with an upsized alternator (K0060124Y21) that increases motor starting capability from 98 sKVA to 124 sKVA at 277/480 VAC with a 30% voltage dip. This is recommended for facilities with large HVAC compressor motors or elevator equipment starting requirements.
