How to Identify Fake Diesel Generators

As we all know, diesel generator set is mainly divided into four parts: diesel engine, generator, control system and accessories. As long as one of them is a fake product, it may affect the overall price and operation performance of diesel generator set. So we should learn to distinguish. Today, Dingbo Power teaches you to identify fake diesel generator sets.

1.Diesel engine

Diesel engine is the power output part of the whole unit, accounting for 70% of the cost of diesel generator set. It is the link that some bad manufacturers like to fake.

1.1 fake diesel engine

At present, most of the well-known diesel engines in the market have imitation manufacturers. For example, Volvo, the diesel engine produced by an enterprise is exactly the same as Volvo engine. They use original Volvo air filter, and mark VOLVO brand on the diesel engine. For example, Cummins, a diesel engine produced by an enterprise, claims that every screw is the same as Cummins, and even the model is very similar. Now there are more and more fake products on the market, so it is difficult to distinguish between true and false.

Bad manufacturers use these counterfeit machines with the same shape to pretend to be famous brands, and use fake nameplates, genuine numbers, printing fake factory materials and other means to confuse the fake with the real, so that it is difficult for even professionals to distinguish.

Each major diesel engine manufacturer has after-sales service stations all over the country. It is stated in the contract with generator set manufacturer that the Seller guarantees that the diesel engine is a brand-new and authentic diesel engine used by the original plant of a certain plant, and the model is not tampered with. Otherwise, the false one will be compensated for ten. The appraisal result of the after-sales service station of a certain plant and a certain place shall prevail, and the buyer shall contact the appraisal matters, and the expenses shall be borne by the buyer. Write down the full name of the manufacturer. As long as you insist on writing this article in the contract and say that you must make appraisal, bad manufacturers will never dare to take this risk. Most of them will make a new quotation and give you a real price much higher than the previous quotation.

1.2 refurbishment of old machines

All brands have refurbished old machines. Similarly, they are not professionals, which is difficult to distinguish. But with some exceptions, there is no identification at all. For example, some manufacturers import the old engine renovation of famous brand diesel generator sets from other countries, because that country also has the famous brand manufacturers. These bad manufacturers claim to be the original imported famous brand diesel generator sets, and can also provide customs certificates.

1.3 confusing the public with similar factory names

These bad manufacturers are a little timid, dare not do deck and renovation, and confuse the public with the names of diesel engines of similar manufacturers.

The old method is still used to deal with such manufacturers. The full name of the original diesel engine is written in the contract, and the after-sales service station makes identification. If it is fake, ten for one leave will be fined. Such manufacturers are timid. Most of them change their words as soon as you say it.

1.4 small horse pulling cart

Confuse the relationship between KVA and kW. Treat KVA as kW, exaggerate power and sell it to customers. In fact, KVA is apparent power and kW is effective power. The relationship between them is 1kVA = 0.8kw. Imported units are generally expressed in KVA, while domestic electrical equipment is generally expressed in kW, so when calculating power, KVA should be converted into kW.

The power of the diesel engine is configured as large as that of the generator in order to reduce the cost. In fact, the industry generally stipulates that the power of diesel engine is ≥ 10% of the power of generator, because there is mechanical loss. Even worse, some reported the diesel engine horsepower to the buyer as kW, and configured the unit with a diesel engine less than the generator power, resulting in reduced unit life, frequent maintenance and increased cost.

The identification only needs to ask about the prime and standby power of the diesel engine. Generally, the generator set manufacturers dare not fake these two data, because the diesel engine manufacturers have published the diesel engine data. Only the prime and standby power of diesel engine is 10% higher than that of generator set.

2. Alternator

The function of alternator is to convert the power of diesel engine into electricity, which is directly related to the quality and stability of output electricity. Diesel generator set manufacturers have many self-produced generators, as well as many well-known manufacturers specializing in only producing generators.

Due to the low production technology threshold of alternators, diesel generator manufacturers generally produce their own alternators. For the consideration of cost competition, several famous brand alternators in the world have also set up factories in China to realize complete localization.

2.1 stator core silicon steel sheet

The stator core is made of silicon steel sheet after stamping and welding. The quality of silicon steel sheet is directly related to the size of stator magnetic field circulation.

2.2 material of stator coil

The stator coil was originally made of all copper wire, but with the improvement of wire making technology, copper-clad aluminum core wire appeared. Different from copper-plated aluminum wire, copper-clad aluminum core wire adopts a special die. When the stay wire is formed, the copper-clad aluminum layer is much thicker than copper-plated. The generator stator coil adopts copper-clad aluminum core wire, which has little difference in performance, but its service life is much shorter than that of all copper stator coil.

Identification method: copper clad aluminum core wire can only use 5 / 6 pitch and 48 slots in the stator of copper-plated aluminum wire and copper-plated aluminum wire. The copper wire can achieve 2 / 3 pitch and 72 slots. Open the back cover of the motor and count the number of stator core slots.

2.3 pitch and turns of stator coil

All copper wire is also used, and the stator coil can also be made into 5 / 6 pitch and 48 turns. Because the coil is less than 24 turns, the consumption of copper wire is reduced, and the cost can be reduced by 10%. 2 / 3 pitch, 72 turn stator adopts thin copper wire diameter, 30% more turns, more coils per turn, stable current waveform and not easy to heat. The identification method is the same as above, counting the number of stator core slots.

2.4 rotor bearing

The rotor bearing is the only wear part in the generator. The clearance between the rotor and stator is very small, and the bearing is not used well. After wear, it is very easy for the rotor to rub against the stator, commonly known as rubbing the bore, which will produce high heat and burn the generator.

2.5 excitation mode

The excitation mode of generator is divided into phase compound excitation type and brushless self excitation type. Brushless self excitation has become the mainstream with the advantages of stable excitation and simple maintenance, but some manufacturers still configure phase compound excitation generators in generator units below 300kW for cost consideration. The identification method is very simple. According to the flashlight at the heat dissipation outlet of the generator, the one with brush is phase compound excitation type.

Above are some ways to identify fake diesel generators, of course, above are only some ways, not complete. Hope the article is helpful to you when you buy diesel generators.