Test/review of 5V 2A Dual USB Port Wall Power Outlet KI09

5V 2A Dual USB Port Wall Power Outlet KI09

Official specifications:

  • Model: KI09

  • Type of terminals: Screw-type

  • Material: PC

  • Number of poles: 2P + E

  • Existence of shutter: With

  • Provision for earthing: With earthing contact

  • USB Output: 5V 2A in total.

  • Input: 100~240V~50/60Hz, 0.4A

  • Rated Voltage(s): 250VAC/50Hz

  • Rated Current: 16A

  • Dimension: 80mm x 80mm x 45mm

  • Color: White

I got it from banggood

I got it in a plastic bag.

The front is clipped can be removed for access to the screws, both for fastening the outlet and for the wires.
If this is removed because something hits it, the outlet gets very dangerous.

When open it is easy to touch mains parts.

The usb supply is a circuit board that is just pushed in.

During my handling of it the frontplate broke, I am not exactly sure how.

  • Power consumption when idle is 0.04 watt

  • Both output are coded as usb charger (DCP)

  • Outputs are in parallel.

  • Earth is not connected to usb shield

  • Need 30mm deep hole.

  • Extend 14mm out.

It is rated for 2A, but can only deliver 1.6A and that is for both outputs together.

The converter used works just a fine on 120VAC as on 230VAC.

I only loaded with 1.5A for the one hour test.
The temperature photos below are taken between 30 minutes and 60 minutes into the one hour test.

M1: 47,0°C, HS1: 81,4°C

HS1: 69,3°C

HS1: 49,6°C

HS1: 82,7°C

M1: 35,5°C, M2: 34,5°C, HS1: 72,2°C

At 0.5A the noise is 15mV rms and 150mVpp.

At 1A the noise is 21mV rms and 173mVpp.

Tear down

The circuit board was just puhsed into some slots and could fairly easy be pulled out.

At the mains input is an inductor, but no fuse. There is a blue safety capacitor.

The led has one of the pins covered (nice detail).

The transformer is extended leads for better isolation distance. The area with solder is for cooling.

On this side there is the bridge rectifier (DB1), the mains switcher (U2: PN8370). There is two rectifier diodes D4 & D5: SS54).

The wrap around a capacitor is not safety rated, this makes this mounting a bit dubious (A layer of heatshrink would have fixed that).

Testing with 2830 volt and 4242 volt between mains and low volt side, did not show any safety problems.


The wall socket has low noise, has low standby power and can nearly deliver the rated current, the usb connectors can be a bit offset compared to the holes in the frontplate.

I will call it useable, but not with children around (Frontplate is to easy to remove/damage and that gives directly access to mains voltage).


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