How do I know if the electric power supplied via USB is OK to drive my gateway?

This article applies to the following models: mPad+, rPad+, rPad+MX, EZ230 and EZ270 

To check if the voltage on the USB host or USB power supply is Ok, enter the gateway administration interface and verify the USB Voltage value. If if drops under 4.0 volts during tags inventory, then you may eventually have a defective cable or insufficient power supply situation:

1. verify the USB cable and make sure it is OK
2. consider using a shorter USB cable to avoid the voltage drop
3. if you're powering-up the gateway using an USB port on a computer:
   1. consider installing a dedicated power supply for the gateway or
   2. install an USB Hub with an external power supply

NOTE: RFID inventory will not start if the USB voltage is under 4.3 volts during the device initialization