Review / UPM USB Meter or Trigger

WEB- U2 USB Meter/Monitor UPM Quick Look

UsbCharging201 Comments

Official specifications

  • Product Model: U2
  • Voltage measurement range: 4-24V
  • Voltage measurement resolution: 0.0001V
  • Current measurement range: 0-5A
  • Current measurement resolution: 0.0001A
  • Capacity accumulation range: 0-99999Ah
  • Energy accumulation range: 0-99999Wh
  • Temperature range: -40℃～180℃ / -40℉～356℉
  • Display screen: 1.77 Inch color TFT 128×160 display
  • Product size: 52.5mm x 34.5mm x 13.0mm

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WEB-U2_Panels_with_Bluetooth_Module.jpg
Panels with Bluetooth Module

Interfaces

WEB-U2_interfaces_01_1
Interface #1.1 Simple interface and large font
WEB-U2_interfaces_01_2
Interface #1.2 Six-digit display
WEB-U2_interfaces_02
Interface #2 Capacity and Energy
WEB-U2_interfaces_03
Interface #3 Equivalent Resistance
WEB-U2_interfaces_04
Interface #4 Fast Charging Protocols
WEB-U2_interfaces_04_1
Interface #4.1 Confirmation of Entering Trigger and Detection Menu
WEB-U2_interfaces_04_2
Interface #4.1.1 Trigger and Detection Menu
WEB-U2_interfaces_04_3
Interface #4.1.2 Trigger and Detection Menu
WEB-U2_interfaces_04_4
Interface #4.1.1.1 Auto Detection
WEB-U2_interfaces_05
Interface #5 Summary
WEB-U2_interfaces_06
Interface #6 Cable resistance measurement
WEB-U2_interfaces_07_1
Interface #7.1 V/A Curves
WEB-U2_interfaces_07_2
Interface #7.2 D+D- V/A Curves
WEB-U2_interfaces_07_3
Interface #7.3 Offline Data Curves
WEB-U2_interfaces_08_1
Interface #8.1 Settings
WEB-U2_interfaces_08_2
Interface #8.2 Settings
WEB-U2_interfaces_08_3
Interface #8.3 Settings

PC Program

WEB-U2_PC_Program_01WEB-U2_PC_Program_02

WEB-U2_PC_Program_03
You may need an on screen translator.

Measurements

Current Accuracy (Brightness Level 1, Loaded)
V A Display A
5 1.00145 0.99942
1.50035 1.49757
2.00060 1.99643
9 1.00145 0.99944
1.50045 1.49725
2.00060 1.99652
12 1.00145 0.99958
1.50095 1.49784
2.00060 1.99642
20 1.00161 0.99957
1.50125 1.49823
Voltage Accuracy (Brightness Level 1, Unloaded)
V Display V (5 Digits) Display V (6 Digits)
5.04615 5.0448 5.04481
9.07260 9.0706 9.07061
12.1102 12.106 12.1067
15.1193 15.115 15.1156
19.9804 19.975 19.9758
Own Current Consumption
V mA, Display On mA, Display Off
Brightness Level 1, USB HID Port On
3.81 20.61 18.27
5.05 20.66 18.43
9.08 20.77 18.46
12.12 20.82 18.50
15.13 20.87 18.62
19.99 20.91 18.71
Brightness Level 1, USB HID Port On, w/ External Power
3.81 0.04 0.03
5.05 1.94 1.68
9.08 20.71 18.33
12.12 20.72 18.35
15.13 20.74 18.54
19.99 20.93 18.61
Brightness Level 1, USB HID Port Off
5.25 19.98 5.53
  • The accuracy of the current is good, but the voltage is not. The voltage needs to be recalibrated.
  • When brightness level is set to 1 and USB HID Port is on, own current consumption is around 21mA with display on and 19mA with display off. When USB HID Port is set to off, it becomes about 20mA with display on and 6mA with display off.
  • The internal resistance is about 32mohm (Includes both connectors).
  • The lowest working voltage is about 2.9V, but it needs to be read in the dark.

Behavior/Logic

This UPM begins to consume external power once the input voltage is lower than the external supply voltage.

—- FW v2.4 —-

  • It behaves like a source with power limited when it triggers/requests the last PPS APDO. When the requested output voltage exceeds the nominal Prog voltage, the it limits the requested output current such that for a PDP Rating of x Watts the requested output current limit is calculated as RoundDown (x/requested output voltage) to the nearest 50mA. So you won’t get the max power even if the source is not PPS power limited.

UPDATE 8/14/2018

  • I overestimated its algorithm. When the requested power (output voltage * max output current) exceeds the PDP, it limits the requested output current such that for a PDP Rating of x Watts the requested output current limit is calculated as RoundDown (x/requested output voltage) to the nearest 50mA. Let’s say, PDP = 30W, Requested Output Voltage = 11V, and the Requested Output Current will be PDP/Requested Output Voltage = 30W/11V = 2.73A RoundDown to the nearest 50mA = 2.70A. So you won’t get the max power even if the source is not PPS power limited.

Bugs

It has some software issues when powered by an external power source, but no such issues without an external power source.

The PD Listener loses packets even when using external power and operating correctly.

Ah and Wh calculation errors. This happens when USB HID PORT is turned off and the screen is off. Some data seems to be missing when the screen is turned off.
web-u2_Wh_Ah_bug

Conclusion

The highlights of this UMP are the interesting action recognition and g-sensor. Other than that, the rest is not very impressed. The factory voltage calibration is not done well. And the own current consumption is a little bit high when the USB HID Port is on. Also, the performance of drawing curves is not very good. In addition, the PC program is very simple and crude. However, new firmware is released often. Hope some of the issues will be fixed in the future.

Mutual Support

The following is a list of files discovered, created, modified, or provided by U2 users to help others. If you are a U2 user and would like to add your work to this list, please leave a comment or contact me.

Thank you all for your hard work!

201 thoughts on “WEB- U2 USB Meter/Monitor UPM Quick Look”

  1. I have a WITRN U2P running latest firmware 9.4. I am facing an issue with it where I see an error on the screen which says – ERR:04: M

    This is new unit & works fine when tested & also goes to DFU mode (except the display). I don’t know how but I disconnected/ reconnected pressed some keys here & there simultaneously and it started to work fine.
    After few days when I took it out, it again stopped working and shows same error on the screen again.

    Is there a way to factory reset it? Please help. Here are the pics:
    DFU Mode: https://prnt.sc/1ushn1k
    Screen Display: https://prnt.sc/1ushsva

    Like

    Reply

  4. There seems to be a new v9.4 Firmware for it.
    http://www.witrn.com/?p=86
    http://www.witrn.com/witrn/U2/U2P_Firmware_V9.4.rar

    I could install it without a problem through the PC Software, but in my case i have a bug with the protocol auto detection. It keeps telling me to remove USB HID cover (i did remove it) and to replug the device.

    Has anybody else tried the new firmware and had any luck with the Protocol Detection?
    Luckily a downgrade to v7.8 works without any issues.

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    Reply

  5. I have picked these USB testers as the best ones currently available for sale: KT002, FL001, FNB48 and U2. Can you advice which one should I pick, which one has better built quality, greater functionality?

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    Reply

    • – FNB48: USB 3.0 connectors, relatively low quality components, Android app, magic smoke.
      – WEB-U2: USB 2.0 connectors, relatively good quality components, average reliability, Android app.
      – FL001: USB-A 2.0 connectors, USB-C 3.0 connectors, relatively OK components, PC and Mac software, not so good FW.
      – KT002: USB-A 2.0 or 3.0 connectors, USB-C 3.0 connectors, relatively good quality components, relatively rich software resources.

      FNB48 is for people who are new to this and want something that seems to work but don’t intend to spend too much on it.

      WEB-U2 is for people who are new to this and want something decent.

      FL001 is for people who have only a Mac.

      KT002 is for people who know what they’re doing and want to do more with it.

      Liked by 1 person

      Reply

  6. Can you help with parts needed for bluetooth module?
    from your picture i can see
    HM-10
    Switch (dont really need this, i’ll jumper to always on)
    Resistor ( dont know the value)
    and 2 other things near bluetooth Logo, what is this?

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    • @Bucky
      The slide switch is HSW4112-010019, but indeed you can short it;
      The resistor is 330 Ohm;
      Two side-emitting blue LEDs are for the logo, but you can use normal 1206 LEDs instead;
      To connect the board (GND+VCC+RX+TX) you either need four 4mm pogo pins.

      While you’re at it, the TFT side can be augmented as well, with 4 red 0805 leds and a 220 Ohm resistor. Two more pogo pins are needed here (for GND+VCC).

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      • Thank you for the part list, i manage to build this module.
        but still have some issue, after change HM10 BT Name to QWAY_U2_XXX and the baudrate, i can see this listed on QWAY Android app, but it doesn’t transmit any data.
        same result when tried to debug using another apps (from another site/blog).

        current config for the BT Module is :
        Baudrate : 115200
        Name : QWAY_U2_XXX (XXX last serial number)
        Did somebody know whats the problem?

        Like

    • 1. connect HM-10 to PC UART (3.3V logic level and power supply)
      -verify connection with AT command
      2. change device name
      -download HM-10 firmware HMSoft-10-2541-V549-LongName.zip
      from http://www.huamaosoft.com/download_rom_en.asp?id=1
      -other firmwares have device name limited to 13 chars which is too short
      -upgrade/downgrade firmware following instructions in HowToUpgradeFirmware_en.pdf
      -connect to HM-10 and change device name to QWAY-U2-123456 with AT+NAMEQWAY-U2-123456
      command where 123456 is QWAY-U2 serial number
      -verify new name with AT+NAME?
      2. update firmware to the latest (or at least to V606) to fix PIN bug
      -download HMSoft-10-2541-V709.zip (it is actualy v710)
      -upgrade FW
      3. change baudrate
      -connect to HM-10 and change baudrate to 115200bps with AT+BAUD4
      -reconnect HM-10
      -try to pair HM-10 and Android device
      -if it cannot pair, try to change bond mode with AT+TYPE2 or AT+TYPE3
      or change PIN with AT+PASS000000 if necessary (6 digits, choose yours)
      4. assebmle HM-10 and QWAY-U2
      5. setup QWAY-U2
      -plug USB cable to USB HID port on QWAY-U2, press and hold M button and connect cable to PC
      -enter into “06 Serial Data Upload” and enable it
      -exit setup mode
      6. install witrn_20210226_V1.3.apk or newer to Android device
      -start app, give permission to storage, BT and location
      -tap buton right to WITRN caption, it should find BT device
      -tap button on the right of device name and address
      -pair devices (enter PIN)
      -tap button on the right (not the middle one)
      -tap on ENGINE START button (round one), it should work!

      Liked by 1 person

      Reply

  8. Thanks for all the information in one place.
    The language file for the pc software is very useful. Sadly there is no English version of the manual anywhere yet (or that I could find)

    I received my U2P today, and it comes with firmware version 7.8 🙂
    The app direct link is broken as stated, but the link to the rar works. For me, the app loaded but did not show anything except the header. The menu button did not expand either. 😦

    Has anyone been able to pair/connect with this meter via bluetooth?

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  11. Also, Does PD-Trigger support PD3.0? or it’s PD2.0 only?
    Does the Tester named “FNB38” supports QC3.0 to PD and PD3.0 Trigger?

    I’m gonna buy one of these, what do you recommend??
    Sorry for my bad English;-)

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    Reply

    • No, your English is better than mine. 🙂 PD-Trigger supports both PD 3.0 and PD 2.0. FNB38 supports QC2.0 to PD and PD 3.0/2.0 trigger, but QC2.0 to PD does not always work even if your charger supports QC2.0.

      – I’m gonna buy one of these, what do you recommend??
      It depends on what you’re looking for.

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      Reply

      • Thanks for reply 🙂

        As I read your reviews about FNB38 and U2, every official features are same except for monitoring graph with PC and screen size. I’m gonna use tester for monitoring my device’s charging speed, check protocols of my chargers, and sometimes use PD trigger and Qc to PD. I don’t require very accurate voltage and current value.

        In this situation, what tester do you recommend? Does the bugs of FNB88 firmware now fixed in v1.3?(or will it be fixed?)

        Like

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