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CDF | Quality Control of Electrical and Electronic Products

8 / 14 / 2020

Do you place orders for the production of electronics, electrical or technical goods in China? How do you guarantee the quality of your products and their compliance with the required specification and functionality?

One of the main reasons for problems with products in this category are the quality of their components, assembly, and soldering.

Earlier in our article "How to set a product’s Quality level for your supplier?" we briefly mentioned CDF as a method for approving the quality of a sample before starting production, along with a list of unacceptable defects and a functionality checklist.

In this article, we will talk in detail about CDF (a component data form) as an important tool for importers of electronics and equipment, its sections and advantages.

To begin with, I will give a real example of checking TWS earphones that did not pass the pre-shipment inspection conducted by V-Trust inspectors.

Case study - TWS Earphones

At the beginning of this year, we in V-Trust were contacted by a US customer with a request to check the quality of a sample and inspect the mass production of TWS earphones.

During the inspection, the V-Trust inspector found that the earphone voltage at full battery discharge (1.45 V) was significantly lower than that of the confirmed sample (3.26 V). The voltage value of the mass produced sample is also lower than the recommended one (4.35 V-2.75 V).

The difference between these two samples meant that the product functionality would be the same, but the battery life of the mass-produced sample would be shorter.

During the inspection of the internal components of the product, it was found that the PCB of the reference sample and the mass production sample were different - different protection system of the boards were used, which was the reason for the low voltage indicators of the mass production sample.

Since the customer did not approve the list of critical components for use in the product, the supplier replaced the PCB in mass-produced earphones. The V-Trust inspector performed an internal product inspection in time and alerted the customer, otherwise the customer would not have known about the substitution of components.

This situation shows how important it is to confirm the use of critical components in the final product and to inspect the product before shipment from the factory.

CDF | Component Data Form

A CDF is a document or series of documents about the internal construction of a product. It is also often referred to as a Critical Component Form or a Construction Data Form.

CDF is used in the development of a sample and its quality control (testing or inspection), applicable to electronic, electrical or technical products.

The CDF documentation can include the list of components and their manufacturers, the compliance of components with standards, as well as the marking of components, the product logo, and other important characteristics of your products. Below is an example:

List of components used

Usually you can obtain a CDF before confirming a production sample with your factory – ask your factory to provide a required test certificate of your item, to see whether the product has been tested and confirmed to be complying with your market’s standards; in this test report, you can find a list of the key components that the tested sample used.

The supplier should use the same components as listed in order to ensure that the mass production samples are of similar quality to the sample that has passed the laboratory test. When your order is in mass production, you can use this CDF to coordinate with us as your inspection company. During the inspection, for the internal check, the inspector will compare the CDF and mass production sample and indicate any differences of the components.

If no discrepancy is found, you can rest easy knowing that the mass production has the same main structure as the certified sample and, consequently, is likely to comply with the international / national quality standard.

If an internal check finds that the product components do not match, it means that your supplier has replaced the product components in mass production, which indicates a risk that the product quality will not be the same as the approved sample, and the product quality certificate for the approved sample may not apply to the mass production sample.

Checking the CDF during product inspection helps prevent the risk of non-compliance with safety and functionality standards.

You can find out what other checking parameters are included in our pre-shipment inspection services by viewing a sample report of our inspection.

At V-Trust, we help control product quality in Asia. Since 2006, our company has offered a wide range of quality control services - product inspections, factory audits, and laboratory tests in China, India, Vietnam, Thailand, Bangladesh and Malaysia.

Visit our website (www.v-trust.com) to learn more about our company and service. If you have any questions, please contact us at info@v-trust.com


V-Trust team
Tatiana Trukhina

- Graduated with honors in Asian Studies at Higher School of Economics
- Delegate on International Youth Summits (BRICS, SCO)
- Experienced in International trade with Asian countries
- 4 years of working in Quality Control industry
- 11 years experience in China
- Fluent in English, Chinese (HSK6) and Russian

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