Dual USB EU AC Power Adapter

DSC_4695

Official specifications:
I got it from Ebay dealer: funfushion

DSC_4694

DSC_4696

DSC_4697

DSC_4698 DSC_4699 DSC_4700



Measurements


Dual%20USB%20EU%20AC%20Power%20Adapter%201A%20load%20sweep

The 1A output can deliver way more than 1A.

Dual%20USB%20EU%20AC%20Power%20Adapter%202.4A%20load%20sweep

The 2.4A output can deliver same current as 1A output.

Dual%20USB%20EU%20AC%20Power%20Adapter%20load%20sweep

This is because they are in parallel.

Dual%20USB%20EU%20AC%20Power%20Adapter%20load%20test

The charger could deliver 2.5A for one hour, but it was to hot to hold after the test.
The temperature photos below are taken between 30 minutes and 60 minutes into the one hour test.

Temp3238

M1: 72,2C, M2: 67,0C, M3: 66,4C, HS1: 77,2C
With the aluminium wraparound the temperature around the charger is mostly equalized, making it difficult to see what parts gets hot.

Temp3239

M1: 65,0C, M2: 65,7C, HS1: 73,8C

Temp3240

M1: 80,2C, M2: 64,8C, HS1: 88,2C

Temp3241

M1: 72,3C, HS1: 73,2C

Temp3242

M1: 64,1C, HS1: 103,1C

10ohm

Noise at 0.5A load is 83mV rms and 555mVpp

5ohm

Noise at 1A load is 126mV rms and 723mVpp

2ohm

Noise at 2.5A load is 160mV rms and 860mVpp



Tear down

DSC_4958

The adapter was clicked together and I could break it open with a screwdriver.

DSC_4959

At first glance it might look nice, but it is not: The two electrolytic capacitors are way to close for safety.
There is an input fuse (F1). The mains switcher is an unmarked IC. Besides the transformer is a opto coupler.
Between the usb connectors is a led.

DSC_4961

The opto coupler is visible from this side.

DSC_4962 DSC_4964

The fuse and the led (LED2) between the usb connectors is visible from here.

DSC_4963

The two capacitors. The top of the 400V capacitors will have mains voltage, but the plastic around the other capacitors is not rated for mains voltage isolation. To make this safe there must be plast, paper or yellow tape between the capacitors.

DSC_4960

On this side we have the bridge rectifier and the rectifier diode (SS56) and the voltage reference (3 pin chip). There is also a led more (LED1).
The usb coding resistors can be seen under the usb connectors.

DSC_4965

DSC_4966

The isolation distance is below 2mm it is supposed to be above 6mm. The CY2 part is supposed to be a safety capacitor, but is just an ordinary one.

The charger failed both 2500 volt and 5000 volt test, this makes the charger dangerous everywhere.



Conclusion

This charger has very bad safety, stay away. It also is bit noisy and gets very hot when fully loaded.



Notes

Index of all tested USB power supplies/chargers
Read more about how I test USB power supplies/charger
How does a usb charger work?