MantisTek&amp;trade; White Tail USB Doctor 4V-15V Voltage 0-3.5A Current Detector Power Tester for Charger Cable Power Bank Discharge Testing<br>Item Description:Input Voltage: 4-15VInput Current: 0-3.5AVoltage measurement error : when 4- 15V ，&amp;plusmn;1%Current measurement error : when 50~3500ma ，&amp;plusmn;1%Maximum Capacity Value : 99999 mAhMaximum Save Data Group: 9<br>USB Port Description:USB1 port : For Charging ， contain CW3002D chip (for universal USB fast charging adapter features)，USB2 port : Data Transmission and also for chargingMircro USB prot: For input use<br>Functional Description:1， When the display is closed， click the button to open the display.Then click the button turns to view data in each group，click one time， the screen will display next group of data， the group of digital flash 5 seconds， after 5 seconds without any operation ， the screen will come back to show the current  group data. Double click the button to switch to the next group of capacity data record; Holding button ( about 2-3 seconds) ， current data will be deleted ;2， 5 minutes without any operation， the display backlit automatically shut down.3， When the voltage is over than 13V or lower than 4.6V， the voltage display data flashing (frequency 1Hz)， buzzer sound alarm (D-， every 5 seconds); when the voltage is higher than 15V， USB port will be shut down automatically in order to protect the device ， and Buzzer will alarm ( Sound :  &amp;ldquo;D &amp;ndash; D &amp;ndash; D &amp;ldquo; ， repeated every 5 seconds ).4， When output current is over 3.1A， the electric current data will flash ( 1Hz frequency)， buzzer will alarm (D-， every 5 seconds); when the output current is over 3.5A， USB port will be shut down automatically in order to protect the device ， and buzzer will alarm ( Sound :  &amp;ldquo;D &amp;ndash; D &amp;ndash; D &amp;ldquo; ， repeated every 5 seconds)5， Over voltage (more than 15V) or over current (more than 3.5A) shut off output， to prevent the twice damage to the load device without monitoring， this item have to be shut down( it means just  take out from power) then use again.<br>The Important Notice:\u25b2Input Voltage must not over 15V， otherwise it may cause permanent damage to the equipment.\u25b2If you use &amp;ldquo;USB load resistance&amp;rdquo; ( sell separately )， must not work for a long time during electric current is over 3A ;\u25b2To ensure the equipment universal fast charging automatic recognition function， power supply voltage shall be 4.6 ~ 15V.