What can I do if the red ERROR LED on the module lights up or there is no communication?
There are several possible causes, please check the following:
- Operating voltage (A1 / A2) connected and sufficient for the device.
- BUS (A- / B+) connected and not reversed. Pay attention to (- / +), not to A/B.
- Address (rotary switches) set correctly, must not occur twice or be 0.
- Bit rate (rotary switches) set correctly, only possible in programming mode (see mounting note).
- Shielded and twisted pair cable used.
- Termination resistor (120 Ω) set on both sides.
- Bias resistors available once on the BUS.
- Max Master as high as the number of physical master I/Os on the BUS.
- Max Frame high enough for all answers from participants to get through (BMT-RTR setting).