Common Mistakes for Selecting Diesel Generators

Diesel generators play a crucial role as emergency power sources in the production and manufacturing of modern enterprises and various critical facilities. They not only provide continuous power supply during power grid interruptions but also meet the special power demands of enterprises in certain environments. Therefore, the selection and configuration of diesel generator sets are vital for the normal operation of businesses. However, due to the wide variety of diesel generators on the market, users are easily misled by unscrupulous manufacturers, leading to improper selection, increased subsequent use costs, and risks. The following will discuss in detail from three aspects: power selection, common misconceptions, and purchasing suggestions, to help users make wiser decisions when selecting diesel generator sets.

Choosing Appropriate Power for Diesel Generator Sets

 
When selecting diesel generator sets, power selection is the key factor in determining whether they can meet the electricity demand. Improper power selection may lead to equipment malfunction and even affect the normal production and operation of the enterprise. Here are some specific suggestions to help users choose the appropriate generator power based on actual needs.

1. Choose Power Based on Equipment's Power Needs

 
For general electrical appliances such as computers, TVs, lights, and lighting fixtures, add their rated power to obtain the total power demand. These devices have relatively low power, and the rated power can be used for calculation.
 
High-power appliances: For appliances like microwave ovens, water heaters, and induction cookers, which have a large starting current, it is recommended to calculate the total power demand at 1.5 to 2 times the rated power to ensure the generator set can handle sudden high-load demands.
 
Electric devices: For devices like air conditioners, water pumps, refrigerators, air compressors, and electric motors, which often have a starting current 2.5 to 3 times the rated power, multiply the corresponding multiple when calculating power to ensure the generator set can provide sufficient power when the equipment starts.

2. Consider the Starting Method of the Equipment

 
When selecting the generator power, do not simply add up the power of all electrical equipment. The impact of the equipment's starting method (direct start, reduced voltage start, or soft start) on power must be considered. For example, when starting directly, the equipment has a large starting current, and a higher power generator set is needed.

Common Mistakes in Diesel Generator Selection

 
There are many brands of diesel generator sets on the market, and there are some common mistakes when selecting them that users need to pay special attention to in order to avoid purchasing unsuitable products.

1. Confusing Relationship between KVA and KW

 
Some unscrupulous manufacturers mislead consumers by treating KVA as KW to exaggerate the power for sale. In fact, KVA represents apparent power, and KW represents actual power, with the relationship being 1 KVA = 0.8 KW. Since imported sets often use KVA to represent power, and domestic equipment uses KW, users should convert KVA to KW when calculating to avoid insufficient power issues.

2. Ignoring Difference Between Continuous and Standby Power

 
Some manufacturers may only mention standby power when promoting power, without mentioning continuous power. In fact, standby power is 1.1 times the continuous power and can only be used for 1 hour in 12 hours of continuous operation. Therefore, users should distinguish between the two when selecting to avoid insufficient power during actual use.

3. Improper Diesel and Generator Power Configuration

 
To reduce costs, some manufacturers configure the diesel engine power and generator power to be the same, or even misreport the diesel engine horsepower as kilowatts, or use a diesel engine with power less than the generator to configure the set. This "small horse pulling a big cart" configuration will lead to a shortened life of the set, frequent maintenance, and ultimately increase the user's usage cost. According to industry standards, the diesel engine power should be 10% greater than the generator power to compensate for mechanical losses.

4. Avoiding Buying Second-Hand and Refurbished Generators

 
There are phenomena in the market where refurbished diesel engines are assembled with brand new generators and control cabinets for sale, which are difficult for non-professional users to identify. Therefore, users should fully understand the brand, origin, and newness of the set when selecting, and ask for relevant quality certifications.

5. Ignoring the Generator Protection Features and Accessories

 
The protection functions (such as four protections) and the configuration of random accessories are crucial in the use of the generator set. Sets above 10KW should be equipped with full instruments and air switches, and large and automated sets must have four protection functions. In addition, the quality and specifications of accessories such as silencers, fuel tanks, fuel lines, and batteries should also be clearly stated in the contract to ensure the safe and stable operation of the set.

Suggestions for Selecting Diesel Generator Sets

 
To ensure that diesel generator sets can meet actual power needs and extend service life, users should consider the following points comprehensively when selecting.

1. Clarify Load Requirements

 
Users should choose the generator power based on the specific power load requirements of the electrical equipment. If the load is mostly equipment like electric motors that require a large starting current, a generator set with a larger power should be selected. For example, for a 50KW electric motor, it is recommended to choose a generator set of about 350KW to cope with the instantaneous high load during startup.

2. Reasonably Plan Power Redundancy

 
To cope with potential future load increases, users should consider power redundancy when selecting a generator set. However, the power redundancy should not be too large to avoid unnecessary cost waste.

3. Choose Reliable Brands and Suppliers

 
When selecting, users should try to choose well-known brands and suppliers with good reputations to ensure product quality and after-sales service. At the same time, it is recommended that users understand the manufacturing factories and brands of the diesel engine, generator, and control cabinet of the set, and comprehensively evaluate the grade and performance of the set.

4. Pay Attention to Accessories and Services

 
In addition to focusing on the main parameters of the generator set, users should also understand the accessories and random services of the set, including the configuration of silencers, fuel tanks, batteries, etc. At the same time, the specific content of after-sales service should be confirmed with the supplier to ensure timely technical support and maintenance services during use.
 
Diesel generator sets, as important backup power equipment, directly relate to the production safety and operational efficiency of enterprises. Users should comprehensively consider power selection, starting methods, equipment configuration, and accessory conditions when selecting, avoid common selection pitfalls, and ensure that the purchased set can operate stably and reliably. Through careful selection, users can not only reduce operating costs but also ensure the stability and continuity of power supply at critical moments.