- 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
|Current Accuracy (Brightness Level 1, Loaded)|
|Voltage Accuracy (Brightness Level 1, Unloaded)|
|V||Display V (5 Digits)||Display V (6 Digits)|
|Own Current Consumption|
|V||mA, Display On||mA, Display Off|
|Brightness Level 1, USB HID Port On|
|Brightness Level 1, USB HID Port On, w/ External Power|
|Brightness Level 1, USB HID Port Off|
- 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.
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.
- 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.
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.
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.
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.
- Official (Up to date): User’s Manual, PC Software, Firmware, Android App, 10/14/19
- PC software v4.2 + firmware v6.3 by bikeribi, 06/14/19
- Official: PC software (Up to date) by Mandos, 01/11/19
- Another place with U2 firmware up to date by bikertibi, 01/11/19
- Official software support: U2 Manual, U2 PC Software v2.3, U2 Firmware (Up to date) by bikertibi, 01/02/19
- Firmware V4.7 11/01/18
- Firmware v4.0 by classicua, 10/14/18
- English language file for PC program by Peter V, 08/28/18
- U2 software package (including manuals, PC program, and firmware V3.3) received from the seller + U2 firmware upgrade instructions (in English) by Tony, 08/28/18
- U2 firmware upgrade simple instructions by Magicmeter, 08/27/18
Thank you all for your hard work!