connecting to quantum with concept over modem


Thread Starter

abraham samson

i am trying to connect to the serial (modbus) port of a modicon quantum using concept programming package over a telephone line using (dlink) modems at both ends. setting is 2400,7,e,1
used procomm to establish the dialed up connection and then exited - the telephone connection is still maintained but connecting concept to the plc over the serial port gives wrong data - seems the message is garbled. tried different options of parity, rtu model, no. of stop bits - doesn't work.
has anyone done this before.
tried concept since modsoft does not work on win2000!

David Doggett

This is not difficult but you must make sure the settings on the modems/PLC and concept match.

Schneider has a application note on how to set up Modems and communicate from Concept to a Quantum PLC using a modem.

You can get this application note as a resolution on "": if you have a support account or you can email me and I will send it to you.

"[email protected]", mailto:[email protected]
Yes this is possible. It is useful to remember that the majority of modems only support 10 bit protocols (Modbus ASCII - this is slow). However, modems are available that support 11-bit protocols (Modbus RTU - faster).
They can be configured at auto-dial a number on a rising edge 5V signal (if the PLC does not use XMIT for example).

We have application notes available. The modems are DIN Rail Mounted and run from high / low AC/ DC.

Follow the link: "":

We have a distributor in the US.

Oscar España

If you dont want to have problems configure PLC in ASCII x baud, E,7,1. Using RTU trough modems can cause problems depending of the time (in RTU frames are separated by 3,2 ms of silent, in ASCII using CR/LF)