I would like two know how can I connect and communicate two micrologix 1200 using modems in order to read information from one PLC to another. Right now, I'm using a SLC500 to communicate with a micrologix 1200 for testing purposes.
There are several different kinds of modems to consider if you are only going to connect two PLCs at a time. There are "wireless" and "wired" modems. Within the "wired" type there are, dedicated line or leased line modems and dial up modems. In all cases, once the modem connection has been established, the communication works just like you had the PLCs connected with a cable. You will use MSG instructions to move the data. The additional tasks will be to get the modems connected.
If you are going to connect more than two PLCs at the same time, then dial-up modems cannot be used as they provide a point-to-point connection. If you provide some additional information on your application, I can provide some additional comments.
