I know the car test. As a test engineer, I have something to say.

Wen No.7-Song

Recently, Know Car Emperor released a series of test results of "Know Car Emperor Winter Test in 2023", and the ranking of pure electric endurance achievement rate of hybrid vehicles will be fried once released. The achievement rate of the minimum cruising range of the test model was as low as 31.6% of the chin, which is equivalent to a bamboo shoot that has not been eaten yet, and most of it has become an old root.

This quickly caused dissatisfaction among many car companies, and questioned that the test standards of Chedi were not standardized and rigorous enough. Huawei Yu Chengdong commented: "cheat people’s test misled people! Science and rigor are the basic rules that should be followed! "

Geely Yang Xueliang said: "I don’t agree with it either. I also think that the evaluation process is unscientific and rigorous, and the conclusion is unconvincing, which not only misleads consumers, but also hurts the credibility of knowing the car emperor."

Things quickly fermented, and I know that in order to prove that the test of the car emperor is credible, today (14th), the winter test open day was held in Mohe at MINUS 40 degrees, and the plug-in/extended-range pure battery life was tested again, and the whole process was broadcast live, and some car companies, media and user representatives were invited to the on-site experience supervision. The test data continues to make people stunned.

Today, we will not discuss the merits, but only talk about testing skills.

Understand how Che Di does winter.

The cruising range achievement rate test?

Knowing that the test of reaching the cruising range in winter is divided into two stages: preparation and testing:

(1) After all vehicles are fully charged with oil on the day before the test, they are allowed to stand in the environment of -20℃ for one night, and then they need to be prepared for one hour before the test the next day;

(2) During the formal test, the pure electric mode will be turned on when the air conditioner is turned on, and then the fuel consumption will be tested by filling up the oil.

There are two main questions about this test:

(1) The procedures of servicing link are rough.

According to the official, the heating time of the air conditioner was too long in the formal test and preparation stage, and there were more than ten times of opening and closing the doors and windows during this process, which greatly increased the energy consumption of the air conditioner and led to a rapid decline in power consumption. Great Wall Motor said that Great Wall Motor retrieved the background data of the tested models and found that some test results were abnormal.

Geely also found a similar situation here. During the preparation process before the test, Yinhe L6 idled for 70 minutes, and opened the door four times, and the longest opening time was more than 10 minutes. Lectra 08 idled for 71 minutes before the test, during which the door was opened 6 times, and the longest opening time was 6 minutes and 39 seconds. These operations have greatly increased the energy consumption of air conditioning, resulting in a lot of power loss before the official launch of the vehicle.

(2) The testing method and final calculation are not rigorous.

Great Wall said that after completing the fuel consumption test, the fuel consumption of each model is different due to the different idle waiting time. Lantu mentioned that Lantu FREE had the situation of opening and closing the door for a long time during the test, in which the left front window was not closed for 306s and the right front window was not closed for 602s during driving.

In short, this time, as an evaluation institution, I know that there are many unreasonable loopholes in the test, and I have been educated by professional automobile manufacturers.

Understand that the car emperor made a mistake.

Professional third-party testing organization

A mistake that will never be made.

As a test engineer, I have a deep understanding of the automobile test process. In the eyes of many people, the automobile test specification is logically clear and needs to be tested extremely rigorously. But in fact, there will be many unexpected situations in practice, even if it is a procedural work, there are often people who make omissions.

In order to strictly standardize the test, professional third-party testing institutions need CMA/CNAS certification.

CNAS accreditation has no restriction on the legal status of laboratories, which can be internal laboratories of enterprises or independent third-party laboratories. The object of CMA laboratory qualification identification needs to beIndependent third-party laboratoryLaboratory of institutions under relevant government departments, etc. These two companies will examine a series of contents such as laboratory equipment, personnel, test methods and program documents to determine whether they are reasonable and compliant.

Knowing that Che Di, as a media, definitely does not have these qualifications. From the point of view of the sky, the business scope does not include automobile inspection business.

To exaggerate, don’t say whether the testers have on-the-job training or not, and they don’t know whether the test instruments they installed have measurement calibration certificates (such as the psychrometer shown below). This is also why there is a voice on the Internet saying that Che Di’s test can’t enter the eyes of professional testing institutions.

Of course, it is impossible for a testing organization to cover all the capabilities, ifSome capabilities are beyond the scope of certification, such as enterprise standards. If a third party wants to do it, it needs to attach a series of statements like the one below. Knowing the car emperor is a "foreign code" and I feel that I am an "authority." A media of this size must make a clear statement.

The above discussion is based on the fact that it has been clear. In addition,Some voices think that car owners have deliberately targeted certain car companies.

Understand whether the car emperor has deliberately targeted some car companies.

This problem is actually more serious, because we have reason to believe that all media have no relevant qualifications. Even if national standards are adopted for testing, they have no qualifications, and in fact they have no credibility. moreoverMost media beat their heads to test the scheme, so we can’t beat them to death just because we understand the qualification of Che Di.

We can’t fully confirm whether some car companies are deliberately targeted. After all, no car companies have issued a statement yet. What if we know that the car emperor is a rough test method and is not strict with all the models participating in the test?

Here I just talk about the general situation of the industry as a test engineer.

Generally speaking, if the vehicle-level test is sent to a third-party testing organization, the vehicle companies will conduct spot checks at all stages of the project, and the third-party testing organization is also obliged to inform the vehicle companies of their current progress and answer their reasonable questions.

If it is a component-level test, generally speaking, the more important the product, the more concerned the car companies are. For example, car companies will deeply participate in the testing of key components such as battery packs, motors and car seats. If the customer is not present, including pictures, words, film records, etc., must be archived. And these original records need more than two levels of personnel to review and review.

However, I understand that during the evaluation, Chedi failed to inform the car companies in advance, conduct live tests, or record videos, which will be difficult to say clearly in the later stage. Moreover, the low-level errors of the switch doors and windows are easy to be found by reexamination, but they are not found inside.

Of course, Knowing Car Emperor held the 2023 Winter Test Open Day today (14th) to test again. However, as far as testing methods are concerned, there are still many loopholes. For example, the following condition mentions that as long as the engine intervenes, the test is terminated. This method is obviously learning the national standard test method, but the national standard method is normal temperature test.

In fact, if it is low temperature (especially in this extreme environment), we must consider the engine waste heat and battery heating strategy. At low temperature, the strategy of engine intervention is inconsistent. At this time, it is meaningless to say that it is unified. Just like PK, a martial arts expert, why can’t Duan Yu be allowed to use Lingbo micro-step, and he can only use the six-pulse Excalibur in a standing pile?

summary

It is a good thing for the media to spend a lot of manpower and material resources on car evaluation. I think the test itself may be really good for users, but the practice is rough. In the end, users feel that it is meaningless, and car companies feel suppressed and both ends are not pleasing.

Moreover, cars are becoming more and more intelligent now. How long the car opens the window and how many times it opens the door can be recorded on the system. These media should also be more rigorous, otherwise there are ways to record the mistakes made for you. Therefore, the best way is to make full records and refine the rules.