GB4943.1 Wireless Charging Foreign Object Temperature Rise Test Kit Figure 47 Figure 48 Figure 49

Figure 47 Steel Sheet (Thermocouple, Plug)

Figure 48 Aluminum Ring (Thermocouple, Plug)

Figure 49 Aluminum Foil (Thermocouple, Plug)

Comes with a set of positioning plates

Product Overview:

The Metal Foreign Object Temperature Rise Test Kit is designed and manufactured to meet IEC62368 & GB4943 standards. It is used to detect the heating of metal foreign objects placed on or near a wireless power transmitter* during operation, preventing burns caused by high temperatures.

Examples of simulated metal foreign objects: phone rings, keychains, metal protective films during wireless charging, or other small metal objects that may be touched nearby. 

Test Steps:

Place the wireless power transmitter* indoors (20~30°C);

Perform one test for each type of foreign object by placing it directly on the transmitter*. Each test consists of four cycles:

— No receiver, foreign object in direct contact with the transmitter*; and

— Receiver in direct contact with the foreign object; and

— Receiver placed 2mm away from the foreign object; and

— Receiver placed 5mm away from the foreign object;

The transmitter* operates at maximum transmission power. (Specific method to consult with the customer)

Note: The test is not intended to measure the temperature of the receiver, so any compatible receiver capable of extracting maximum power from the wireless power transmitter* can be used, and there is no need to monitor the receiver's temperature.

During each cycle, the foreign object can be moved on the transmitter* to find the position that generates the highest temperature.

Judgment Criteria:

During the test, the temperature of the foreign object must not exceed 70°C.

As for why it is 70°C, I think it can be linked to the limit in 9.3.2.