Good Morning

Has any one had a problem that they have 4 sensors that there output is only a communica protolcal that is RS485, and needs to use the inputs on the logo, I know that siemens just released Logo! CIM but it onlt takes one RS485 Sensor.

Is there a way that i can connect muliple CIM or is there any other module that i can connect to the CIM so that i can connect the other sensors.

Thanks

Mark Paul Busuttil.

MPBusuttil

 released Logo! CIM but it onlt takes one RS485 Sensor.

Is there a way that i can connect muliple CIM or is there any other module

Physically RS485 enables 32 devices on single bus, so when all sensors are set to same baud rate/parity/stop bits and with different modbus addresses (slave ID-s), then one master module can access multiple sensors. CIM manual page 63 specifies data transfer table options for MB RTU master.

Another (cheaper) way is to use Logo BM 8.2 or later and Microtik Knot with IoT package, which can convert RS-485 Modbus RTU data to Modbus/TCP.

Hi,

LOGO! CIM supports ModbusRTU interface. You can connect several similar sensors (RS232, RS485 or RS422) to a LOGO! CIM. The sensors are seperated by the ModbsuRTU unit-ID.

Hello MPBusuttil;

The proposed solution (Modbus RTU over RS 485) will only work if the sensors you have can act as Modbus RTU slaves.

Please statt by identifying the make and model of the selected sensors, so we can locate their operating instructions, and make sure Modbus RTU is supported. If the sensors can work as Modbus slaves, there will be no problem in connecting them to the Logo! master and collecting data from each.

Hope this helps,

Daniel Chartier 

Your attachment doesn't help, these are internal descriptions on how to use modbus commands.

Offer a link to your sensors with a complete instruction manual.

By the way, Modbus RTU slaves need different ID numbers to work with one master. Depend on the sensors this is programmable with a PC or selectable with DIP switches.

Regards, Scorp