When buying a diesel generator set, there are several key factors to consider to ensure you choose the right one for your needs.
Power Requirements:
First, determine the total power requirements of the equipment you’ll be using. The diesel engine should be at least 30% larger than the required power, and the generator should have a 10% reserve power. For large electric motors (non-inverter start), the diesel engine’s power should be three times the motor’s power to ensure smooth startup.
Brand and Pricing:
Choose a diesel engine and generator brand with mature technology, low fuel consumption, low maintenance costs, and high reliability. For the generator, it’s recommended to select one from a reputable domestic manufacturer of brushless motors.
Control Unit Selection:
Depending on the use environment, choose the appropriate control unit. For industries like rentals or companies that may not be familiar with LCD screens, a manual screen may be more suitable. For high automation requirements, opt for a fully integrated LCD screen.
Avoid Deceptive Practices:
Be cautious of dishonest manufacturers who may misrepresent the power of the diesel engine or generator. Always inquire about the cooling system and check whether the generator is made from pure copper.
Fuel Efficiency:
Diesel engines should be selected based on fuel efficiency and low maintenance costs. Consider engines from brands that are known for their technological maturity and reliability.
Understanding Diesel Generator Principles:
Diesel generators are made up of a diesel engine and a generator. The engine powers the generator to produce electricity. The basic operation of a diesel engine involves the piston moving through four stages: intake, compression, power, and exhaust. This process creates mechanical energy that is then converted into electricity by the generator.
Avoiding Common Pitfalls:
There are several traps buyers should avoid:
- Confusing KVA with KW: KVA represents apparent power, while KW represents real power. The relationship between them is KVA = 0.8 x KW.
- Misrepresenting continuous and backup power ratings: Backup power is only usable for a short period.
- Using an engine that is too small: The engine power should be at least 10% greater than the generator’s power rating to account for mechanical losses.
- Selling refurbished engines as new: Be sure to check if the engine is new or refurbished.
The Role of Cooling Systems and Components:
The cooling system is essential for maintaining the generator’s efficiency. It’s crucial to ensure that the cooling tank and other components like the fuel tank and battery are included, and check the type of battery included with the generator.
Selection Based on Usage:
The choice of a generator should be based on its intended use. Whether the generator is for continuous operation, backup, or emergency use will affect the specifications you need.
Consider Environment and Maintenance:
Environmental conditions such as temperature, humidity, and altitude can affect the performance of the generator. It’s important to specify these factors when purchasing, especially for large generators.
Generator Selection Criteria:
Factors like mechanical and electrical performance, the required load, and the environment need to be considered. Diesel generators are used for common, backup, and emergency power needs, so different requirements apply based on the type of use.
Common Diesel Generator Selection:
For continuous use, the generator should be able to handle varying loads and operate efficiently for extended periods. Selecting multiple generators can help ensure continuous power supply, allowing for load management and reducing fuel consumption.
Emergency Diesel Generator Selection:
Emergency generators should have high-speed, low-fuel-consumption engines and should be reliable in critical situations. These generators often require features such as automatic start-up and specific load-handling capabilities.
Starting Methods:
Diesel generators can be started manually, electrically, or with compressed air. High-rise buildings generally require electric start-up to ensure reliable operation during power outages.
Matching with Electric Motors:
When matching a diesel generator to a motor, consider a safety factor of 1.5 times the motor’s capacity (if soft start is used).
Recognizing the Brand:
When purchasing a diesel generator, it’s essential to know the brand of both the diesel engine and the generator itself. Many foreign generators are assembled, while some domestic generators feature integrated systems from the same brand.
Conclusion:
Purchasing a diesel generator requires careful consideration of various factors including power requirements, brand selection, cooling systems, and intended use. Always verify product details and ask about the components used to avoid common mistakes. With the right knowledge and careful selection, you can ensure that your diesel generator provides reliable and efficient service for years to come.
