10 indicators to judge the performance of diesel genset

Diesel genset are the core equipment for industrial, commercial and household backup power supplies. Their performance directly affects power supply stability, operating costs and long-term reliability. Faced with complex product parameters on the market, ordinary users often find it difficult to accurately judge the pros and cons.

1. Rated power (kVA/kW): Matching requirements is the basis

1 Rated power refers to the maximum effective output power of the generator in continuous operation. The units are usually kVA (apparent power) and kW (active power). The conversion relationship between the two is kW = kVA × power factor (generally 0.8).
2 Users need to calculate the actual total load power and ensure that it accounts for 70%~80% of the rated power of the generator to avoid long-term full-load operation.
3 Pay attention to the difference between main power and standby power. Standby power is only suitable for short-term emergency use and cannot be used as a regular output standard.

2. Fuel efficiency: saving fuel is the core indicator of saving money

1 Fuel efficiency is defined as the amount of fuel consumed per kilowatt-hour of electricity generated (unit: L/kWh). The lower the value, the more economical it is.
2 When comparing different models, it is necessary to refer to the data under ISO 8528 standard test conditions. Ambient temperature 25°C, altitude 100 meters, load rate 75%.
3 High fuel efficiency models can significantly reduce long-term operating costs, especially in continuous operation scenarios.

3. Voltage stability: ±1% fluctuation determines equipment safety

1 Steady-state voltage deviation must comply with the national standard GB/T 2820, and the fluctuation range should not exceed ±1%.
2 When a sudden load is applied, the time it takes for the voltage to return to a stable value should be less than 4 seconds to avoid damage to precision equipment.
3 It is recommended to use a professional meter to monitor the harmonic distortion rate under non-linear loads (such as motors) to ensure that it is less than 5%.

4. Noise level: A technological breakthrough from 90dB to 60dB

1 Industrial scenes can accept 85-90 decibels of noise, commercial buildings need to control to 75-85 decibels, and sensitive environments such as hospitals or data centers should choose 60-75 decibel silent models.
2 Noise reduction technologies include silent hood design, exhaust muffler optimization, and low-speed operation (1500 rpm is better than 3000 rpm).

V. Emission standards: Balancing compliance and environmental costs

1 The National III standard stipulates that the nitrogen oxide emission limit is 7.0 grams per kilowatt-hour. And the particulate matter emission limit is 0.2 grams per kilowatt-hour.
2 The Euro V standard requires that nitrogen oxides do not exceed 2.0 grams per kilowatt-hour. And the particulate matter limit is 0.02 grams per kilowatt-hour.
3 The EPA Tier 4 standard limits nitrogen oxides to 0.4 grams per kilowatt-hour. Particulate matter is also 0.02 grams per kilowatt-hour.
4 Exports to the European and American markets must comply with EPA or European standards. It is recommended to choose models above the National IV standard for sensitive domestic areas.

6. Cooling system: the trade-off between air cooling and water cooling

1 The air cooling system has a simple structure and is easy to maintain, but the heat dissipation efficiency is low, and it is usually suitable for small-power generators below 50 kilowatts.
2 The water cooling system dissipates heat evenly and is suitable for high-power models, but the antifreeze needs to be replaced regularly, and the maintenance cost is high.
3 Regularly check whether the air inlet of the air cooler is blocked, and the water cooler needs to prevent the risk of water pump failure and water tank leakage.

7. Start-up performance: reliability test in low temperature environment

1 The starting battery capacity must be above 200 Ah, and support low-temperature starting at -20°C.
2 The glow plug preheating system should complete the cylinder temperature rise within 30 seconds, and an oil pan heater can be installed in extreme environments.
3 Preheating technology commonly used in polar research stations ensures that the generator starts normally at -50°C.

8. Load Response Capability: “Shock Resistance” When Sudden Load is Added

1 When a 100% load is suddenly added, the frequency drop must be less than 12% and the recovery time must not exceed 5 seconds.
2 A staged load test (25%, 50%, 75%, 100%) can be performed to observe whether the voltage fluctuation curve is smooth.
3 The electronic speed regulator responds faster than the mechanical speed regulator, and the optimized design of the flywheel inertia can improve the impact resistance.

9. Maintenance convenience: from daily maintenance to overhaul costs

1 The maintenance cycle of a high-quality generator can reach the first oil change every 500 hours, reducing the maintenance frequency.
2 The air filter and oil filter should be designed as a quick-disassembly structure to reduce downtime.
3 Models equipped with LCD screens can display maintenance reminders in real time to improve operation and maintenance efficiency.

10. Brand and after-sales service: the key to hidden costs

1. Give priority to brands with sufficient spare parts supply to ensure that wearing parts such as piston rings and fuel injectors can be replaced quickly.
2. Manufacturers need to provide a 24-hour emergency service network, and users in remote areas should focus on the response speed.
3. Warranty terms must clearly cover core components such as engine cylinders and crankshafts, and the warranty period is recommended to be more than 3 years.

Users need to weight and evaluate the 10 indicators according to the actual scenario requirements:
1 Precision scenarios such as data centers prioritize voltage stability and quietness.
2 Continuous operation environments such as construction sites focus on fuel efficiency and maintenance convenience.
3 Special scenarios such as ships or polar regions need to focus on corrosion-resistant design and low-temperature startup capabilities.
Through systematic analysis, users can avoid inefficient or low-quality products and achieve the optimal balance between performance and cost.