The USB Fieldbus Interface is capable of working in two power modes:
-
Mode 1 - The interface does not supply power to the connected
fieldbus device or segment. The fieldbus device or segment is powered by an
external source.
Mode 1 is the default.
-
Mode 2 - The interface powers the connected fieldbus device or
segment and no external power is needed.
The interface is capable of powering multiple devices on a fieldbus segment through an external USB hub. It can provide current of up to 85 mA (typically sufficient for three or four fieldbus devices on the same segment).
You can configure Mode 2 using the Fieldbus Interface Configuration utility. For more information, see Power fieldbus devices.
Warning: Choose only one power mode. Never attempt to use two
power sources at the same time. Doing so can disrupt communications and may
compromise automation safety.