Applicable Systems
S7-1200
S7-1500
S7-300
S7-400
LOGO!
SINAMICS
Symptoms
Modbus RTU slave device not responding to requests.
Possible Causes
Slave address incorrect, baud rate mismatch, cable disconnected, or slave device powered off.
Troubleshooting Steps
Verify slave address, check communication parameters (baud, parity), inspect RS485 wiring.
How to Reset
Fix communication and restart
Source: Siemens S7-1200/1500 Modbus communication
Category: PLC & VFD