is all you need! It can show you the USB charging current and voltage instantly. Through it you can quickly find out device's current and voltage stage, like USB cable, USB wall charger, car charger or solar panel charger, which gives you the fastest charging performance! Flexible, easy to use. KCX - 017 USB Current and Voltage Meter reads the charging status to you in real-time style! 


Features:
It can test current and voltage of phone, mobile power bank etc.
With a USB port and micro USB interface, convenient to test devices
With LCD screen, easy to see the current and voltage of the devices
Press the small circle button and the data will be zero, then you can test next data

Parameters:
1. Input Voltage: 3 - 7V
2. Input Current: 50mA - 3500mA
3. Capacity: 0 - 19999mAh
4. LCD show voltage and current simultaneously
5. Save data each time power off
6. High precise current calibration function
7. High and low voltage alarm Model: KCX - 017
Design: Professional
Feature: Portable
Function: Text Current and Voltage
Interface: USB2.0
Package weight: 0.044 kg
Product Size (L x W x H): 6 x 2.8 x 1.5 cm / 2.36 x 1.10 x 0.59 inches
Package Size (L x W x H): 7 x 4 x 3 cm / 2.75 x 1.57 x 1.18 inches
Package Contents: 1 x Current Voltage Meter
For iPad original charger, connected to 2A load resistor, the output current and voltage is 5.01V 1.89A

For iPad original charger, connected to the 2A load resistor and mobile phones, the measured value of the maximum current and volatage is 5.01V 2.28A , very good charger. 
Use 2A load resistor to connect with Salcomp (a Nokia company) charger, the output and volatage is 5.01V 1.89A 
Connect 2A load resistor and mobile phones to Salcomp (a Nokia company) charger , the measured value of the maximum current and voltage is 5.06V 2.20A, very good charger.
Mobile power connector USB HUB for mobile phone charging, the measured voltage and current values 5.00V 0.44A 
Mobile power via USB HUB, connected to the 2A load resistor and mobile phones, the measured value of the maximum current and voltage 4.86V 1.96A, still good mobile power.
The second group of pictures USB data cable tests
1m original data cable of LG, 1A current charger, USB tester, test result 4.8V 0.92A 
1.5m original data cable of Samsung, 1A current charger, USB tester, test result 4.80V 0.92A 
Orange data cable, 1A current charger, USB tester, test result 4.22V 0.81A. This cable quality is no good. 
Mobile power discharge capacity test
Beginning discharge is 0001mAh 
After 10 minutes the discharge capacity is 0164mAh
We conclued that the charging current is 0.98A, after 10 minutes the discharge capacity is 164mAh.
Note: This data is mobile power discharge capacity, not battery capacity. According to our experience, the mobile power discharge capacity is about 1.9 times of the battery capacity.