Main quality indicators of power adapters

At present, the power adapter according to the different supporting electronic and electrical equipment, respectively use the national standard "GB4943-2001: information technology equipment safety" and "GB8898-2001: security requirements for audio, video, and similar electronic equipment shall be used as the quality assessment standard. For example, power adapters for laptop computers, cellular phones, and other information equipment shall comply with the requirements of the national standard gb4943, the power adapters for audio and video devices, such as the language repeater and Walkman, must comply with the requirements of gb8898. The following describes the main performance indicators stipulated in several standards: 

Rated output current
It refers to the output current of a manufacturing plant under its nominal rated power supply voltage and rated frequency according to the operation conditions specified by the power adapter.

Rated output voltage
It refers to the output voltage of a manufacturing plant that outputs the rated current value under its nominal rated power supply voltage, rated frequency, and rated power according to the operation conditions specified by the power adapter.

Tag and usage instructions
Marking is an important information that instructs the user to correctly install and use, and is the most basic security content to ensure the security of the user's personal and property. Labels must be durable and eye-catching. When considering the durability of tags, the impact on tags during normal use should be taken into account. Products sold in China must use simplified Chinese characters and at least contain the following information: name, trademark, or identification mark of the manufacturer or distributor; Model Code or model specification; nature of power supply; rated Power Supply voltage range.

Power plug size
China's household single-phase power plug has two forms: bipolar grounding and bipolar grounding.
The standard plug should be able to prevent the insertion of a single pole. That is, when either plug pin is inserted with the live plug-in of the socket, other plug-ins cannot be in the easy-to-touch status. According to national standards, when there is no grounding between poles, the pin length is 16 ± 0. 35mm, and the pin length is 18 ± 0. 35mm.

Electric shock hazard under normal working conditions
During normal operation, dangerous live parts should be inaccessible. If there is a ventilation hole in the adapter shell, it shall be ensured that the hanging foreign objects will not become dangerous charged parts when entering the ventilation hole, the knob used on the adapter to change the voltage setting or to change the positive and negative performance of the output and the shaft of the joystick should not be charged, and the shell should have sufficient strength to resist external force, after manually removing the protective cover, components that can be touched should not be dangerous and charged.

Normal operation fever
Heating is the requirement for the normal operation of the power adapter. When the voltage is changed under normal working conditions, because of the loss, some electric energy needs to be consumed. After the electric energy is converted into heat energy, the temperature of the product increases. Due to the limited heat resistance of insulation materials, when the internal temperature of the equipment is too high, the insulation material will rapidly aging, resulting in reduced safety performance, the electrical and mechanical properties of the product will also be adversely affected for a long time, the components and parts also reduce their expected service life. Therefore, the standard requires that when the product is in a stable state, the temperature of the parts of the device should not exceed the standard range. In order to ensure the normal operation of the supporting equipment, the standards also stipulate that protection devices that affect the safety of the equipment, such as hot circuit breakers and overcurrent protection devices, should not be operated under normal working conditions.

Fault conditions
If the internal components are short-circuited due to long-term aging or the output is short-circuited due to incorrect operations, the power adapter may experience abnormal work or faults. At this time, due to the sharp increase of internal losses, the temperature of each part is increased, and even the equipment is damaged. According to the standard, the power adapter may be damaged in the case of abnormal work or failure, but the safety performance of the equipment cannot be reduced, and it should still be protected by electric shock. The temperature rise of each part of the device shall not exceed the requirements, and the items around the device shall not be in fire danger, and the shell shall not be deformed to affect the safety requirements. According to gb8898, the temperature rise of the power adapter housing (non-metallic casing that can be touched) should be less than 65 ℃ under fault conditions.

Mechanical Strength
The power adapter should have sufficient mechanical strength and its structure should be able to withstand the operation and handling tests that may be encountered during intended use. The standard requires that the product be able to withstand 3 drops from 1 high to the horizontal ground in the way that the most adverse results are produced. After the test, the product is not required to be usable but cannot affect the safety. When the torque of nm is applied to the pin, the pin should not be rotated; when the rated current is less than or equal to 10a, the pin without grounding at the pole is applied to 40n or the pin with grounding at the pole is 50n, pin displacement shall be less than or equal to 1mm.