If you have more than 1 USB device that you need to connect to the NEXUS-NERO, you can use a USB hub to give you more ports.
NERO only provides a small amount of power on the USB port, we recommend you always use a powered USB hub when connecting multiple devices.
You may wish to use more than one USB if you wish to connect the NEXUS-SECURE Alarm Panel as well as record logging from the NEXUS-NERO.