Answer: D. DeviceNet
Answer Analysis:
The fieldbus used by ABB industrial robots in the training base is the Devicenet bus.
Devicenet bus is a network for connecting factory equipment, which can operate up to 64 nodes, that is, 64 slaves are allowed to be connected on a network, and the available communication baud rates are 125kbps, 250kbps and 500kbps.
The device can be powered by the Devicenet bus or by a separate power supply.
A robot that supports the Devicenet network can act as a master for lower-level devices, or as a slave to PLCs or other devices that can act as masters.