USB power meter/tester thread - YZXStudio, Power-Z, RDTech and more.

Baseus PD car chargers are trash and DANGEROUS. I bought two of the 30W PD + USB A on sale and both failed safety and functionality tests.

The problem you’re describing is mainly because the charger only works in BUCK mode, which is not specified anywhere so in order to achieve 45W output which is 15V3A you must have it connected in a 24V vehicle. Charger is unable to output above 9V and will restart when such voltage is requested.

Secondly the USB A and usb C port are not well isolated for “dumb” usb devices. Normally when you connect a 9V and a 5V device simultaneously the charger must restart to provide 5V on both ends in case it can’t provide both 9V and 5V at the same time, however with the baseus car charger it will simply provide whatever voltage it’s on the C side as long as the A port device isn’t requesting any specific voltage.

In order to perform the above test I used iPhone X with fast charge cable and a cheap lantern that I quite liked on the other end and the instant 9V charging via micro USB blew the resistors. $10 lantern lost because of a $5 charger.

I like that Baseus charger because displays the voltage of the car, the voltage being outputted and the amperage being outputted.
I have used TC66C on a 24V car and has the same issue, it’s not the voltage that makes TC66C reset when doing PROTOCOL DETECTION.

[quote=RD tech]

Ok did some more tests and this is what I’ve found:

- TC66C Firmware upgraded from 1.13 to 1.14

- Now if I connect the TC66C directly to the C port of the Baseus your meter doesn’t turn on: Baseus <-> TC66C
— However if I use C to A and A to C adapters in the middle then it turns on: Baseus<USB C to A<>USB A to C<->TC66C. Why is this difference happening, is that the adapters modify something in the middle?

- If I connect the TC66C to the A port on the Baseus I need one A to C adapter and turns on again without load.

  • PROTOCOL DETECTION detects everything as green when connected to C port on the Baseus and battery is 24V. If I connect to A port it’s the same result but TYPE-C PC is red instead.

  • Which protocol Baseus does not meet properly?

While using C to A and A to C again you will just have the A protocol.

Looks like the Baseus is causing the problem.

Using just one of them already implies using A protocol? I though all data was preserved and it was just a physical change.

Yes, since USB A has just 4 wires (+5V GND TX and RX) whereas USB C has 24.
Data will be preserved though. But you loose all the options of USB C

More info on the issue:

- When connecting TC66C or any other USB-C power meter, like Satechi or Plugable, directly to Baseus C port, power meters don’t power on until I connect some load like charging a phone. If disconnecting the load, the meter powers off again.

  • However, If I connect a USB-A meter like YZXstudio to the A port of the Baseus, it powers on immediately even with no load.
    Doesn’t this make sense, since PD prevents from sending power until some specific bus data is received? Or power meters already send some signal so it should power or? I don’t have any other PD wall or car charger to test it so I don’t know how it should behave.

[quote=xnode]

Now if I connect the TC66C directly to the C port of the Baseus your meter doesn’t turn on: Baseus <-> TC66C—- this is not charger and TC66C problem, this is PD charger feature, if you want it turn , please turn on our PD switch, it will turn on

Tried again connecting TC66C to C port of Baseus, but still doesn’t power on without load. Tested with buttons C and D of the meter in all 4 available positions but still doesn’t turn on.

thank you for your reply, could you make a video to show me ?

Hi, I sent you the video to your PM. You can see how I connect the meter in all 4 available positions of the switches, and it never turns on witout load. With load, sometimes the meter screen powers on and others not, but always charges the load when connected. By the way, the car charger specific model is the Baseus BS-C20C, it’s written on the case.

Related article: The Baseus BS-C20C in the test! USB PD, QC 3.0 and Huawei Super Charge in one car charger for € 10?!?

please turn on the PD switch and PWM switch on

I already tested with them on, I do not understand what else is missing.

Ok finally found how to turn on TC66C meter when it’s standalone connected to PD port of Baseus BS-C20C. You need C physical switch on (POWER) + D physical switch on (POWER DELIVERY) + AG virtual setting ON on Settings menu (CC line mode choice / PD SOFTSWITCH). The 3 are required enabled to turn on. I had the AG setting off thus didn’t turn on without load even with the other two on.

did you solve the problem by turning on both switch

you are professional

Hello again, I’ve found another issue with TC66C and Baseus BS-C20C:

Connect TC66C to Baseus in PROTOCOL DETECTION mode, then use a power supply to power the Baseus.
1- Set power supply to 13 vols and do protocol detection
2- When finished, increase power supply voltage from 13 to 24, with power supply still ON, do not disconnect voltage source.
3- Now when trying to perform protocol detection again the TC66C turns off and on again.
4- Same thing happens when lowering voltage from 24 to 13
5- Happens on both USB-A and USB-C port
6- Other Baseus car chargers that don’t have 20V output the issue does not happen.

Hi guys,

Has anyone ever successfully upgraded the firmware on a Power Z KM001 or KM001C? o

I have been using this to do some capacity tests and whenever I connect to the PC software to start a graph. I am promoted to update.

Any help would be greatly appreciated. Great device but a horribly translated manual.

Latest firmware version (as per using the Power-Z app to do a firmware update "Check"

Change Log copied from the App's info box (translated via Google Translate):

Power-Z App v1.4.5 including the v1.4.4 (2020/04/24) firmware

https://kingmeter-1255476733.cos.ap-guangzhou.myqcloud.com/Power-Z.zip

v1.4.4 changelog from readme file (translated via Google Translate)

Click the "Firmware Update" tab:

Then click the "Check", which will then show this screen.

Select the correct firmware (for KM001 or KM001C, depending on your device), then click "Upgrade"