Mobile phones have become a must-have item in modern people's daily life. The most worrying thing when using a mobile phone is the power problem, so the pursuit of larger battery capacity and faster charging technology has become an important topic in the development of mobile phones. But an important link in the charging process is often easily overlooked, that is, the charging data cable.
The charging data cable is the only way to connect the mobile phone and the charging stand, but it is such an important and irreplaceable part. Many people will be in danger because of greed for cheapness. As early as a few years ago, China Fire Department released a video of a fire caused by burning data cables; the same thing happened again in July 2021. A news report about a sudden explosion of a charger also made people look sideways and terrified. The reason is that the charging data cable is poor in quality and aging, causing the charger to short-circuit and explode.
Not long ago, the China Consumers Association released the data of the comparative test report of 46 charging data cables. The test results showed that of the 46 charging data cables purchased from different e-commerce platforms, only 14 performed well in all 8 tests, and nearly half of the samples had poor flame retardancy; nearly half of the samples had weak corrosion resistance and the metal parts were prone to rust; 26% of the samples had unsatisfactory voltage drop test results.
Eliminating hidden dangers is also improving charging efficiency
The data cables on the market look highly similar in appearance, but their internal quality varies greatly. In order to ensure the safety of charging data cables in use, it is necessary to require the data cables from several aspects.
We all know that after the power data cable connects the mobile phone to the charger, it is equivalent to a resistor in series in the circuit, and the current passing through will cause power loss. The size of the resistance value determines the amount of loss efficiency. The more the power efficiency is lost, the lower the actual charging efficiency will be. At the same time, the lost efficiency will be manifested in the form of heating of the data cable, causing safety hazards. We can use the "voltage drop" indicator to judge the charging efficiency of the charging data cable. Due to the resistance of the data cable, voltage will naturally be generated at both ends of the wire. The value of the voltage drop from the charger end to the device end of the data cable is the voltage drop value. According to YD/T 1591-2021 "Technical Requirements and Test Methods for Power Adapters and Charging/Data Interfaces of Mobile Communication Terminals", it is recommended that the voltage drop of the charging data cable should be less than 750 millivolts.
Special situations can also ensure safety
After solving the problems that may occur during normal use, the next step is to ensure that no accidents will occur and damage the charging equipment when special situations (voltage increase, line short circuit, etc.) occur. This requires testing the voltage resistance and insulation resistance of the power data line. According to the standard requirements, the insulation material of the USB A type connection interface should be able to withstand an AC voltage of 500V, and the insulation material of the Micro-USB B, Type-C and cylindrical connection interface should be able to withstand an AC voltage of 100V. In the withstand voltage test lasting 1min, no breakdown, sparking or arcing occurs, and the leakage should not exceed 0.5mA. The insulation resistance between adjacent contact points should be no less than 100MΩ.
Accidents occur, but there is still protection
If the power data line is self-ignited or ignited due to improper use or accident during use, it will cause personal and property safety hazards. The last layer of protection is required, requiring the charging data line to have good flame retardancy. When a data line that does not have flame retardant properties encounters fire, it will quickly burn until the combustible material carbonizes and falls off. In actual use, once the data cable touches an open flame, it is easy to cause a fire hazard.
Flame retardancy mainly refers to the insulating material part of the cable. The flame retardancy of the insulating material of the connector part of the qualified charging data cable should reach V-1 level or better; the flame retardancy of the insulating material of other parts should reach VW-1 level (VW-1 vertical burning) or better.
After these three aspects meet the standard requirements, we can basically guarantee our safety when using the data cable. However, we should also pay attention to some precautions during actual use. First of all, we should replace the damaged power data cable in time. The damaged cable part may cause a short circuit due to contact with the external environment; secondly, avoid bending during use. Bending will damage the external insulating material and may also cause a short circuit in the internal cable. Use the charging data cable safely to ensure the safety of every charge.
