Cause: indicates that the network communication timeout.
Countermeasures:
① Check the main station must use the same baud rate from the station;
② Check the wiring of communication cable is loose;
③ whether the two terminals of the network terminating resistor;
④ check the current speed and distance network, consider reducing the baud rate of the network, using 125Kbps baud rate for communication;
⑤ recommended DeviceNet dedicated cable network;
⑥ Whether there is signal interference around the communication apparatus.