RCOM/RCOM+ Protocol

RCOM is a transmission protocol which is particularly suitable for data transmission over long distances (RCOM = Remote COMmunication).

The protocol is based on a simple V.24 interface and thus permits the use of standard data teletransmission devices (e.g. modems).

The main fields of application for RCOM are as follows:

• Coupling from Advant Controller 31 to ABB MasterPiece control systems
• Networking AC500 systems to AC31 systems
• AC500 stations and AC31 stations
• Networking of AC500 stations

You can use either dedicated lines (e.g. existing cable paths or leased lines) or telephone lines with dial-up modems for communication.

Differences between RCOM and RCOM+

There are the following differences between RCOM and RCOM+ concerning data transmission:

• The “BREAK” character of RCOM is replaced by a transmission break of configurable length for RCOM+
• The 8 bit “exclusive-or check sum” (XOR) of RCOM is replaced by a 16 bit CRC16 check sum for RCOM+

Switching between RCOM and RCOM+

Switching between RCOM and RCOM+ is performed by selecting the corresponding operation mode in the PLC configuration Configuring the RCOM/RCOM+ Communication Module CM574-RCOM.

• RCOM Networks
• Job Types
• Data Transmission
• Planning
• Error Codes
• Operator Terminal