Toshiba VF-A7 - Manual (Page 28)

27
10. Modbus TCP/IP
The ETH-100 interface supports Schneider Electric’s Modbus TCP/IP protocol,
release 1.0. The ETH-100 is conformance class 0 and partial class 1 compliant, and
allows up to 8 simultaneous Modbus TCP/IP client connections (sockets). Socket
timeouts are set to 30s, which means that if a particular open socket experiences no
activity for more than 30s, then the interface assumes that the client has experienced
some sort of unexpected problem, and the ETH-100 will close that socket.
10.1 Drive Channel Access
Each specific drive channel (Channel A, Channel B and Channel C) is accessed via
the “Unit Identifier” (UI) field of a Modbus TCP/IP packet. Drive channel A is
accessed when the UI field is set to “1”, channel B is accessed when the UI field is
set to “2”, and channel C is accessed when the UI field is set to “3”. Any other UI
setting is invalid and will result in a GATEWAY PATH UNAVAILABLE exception
(Modbus TCP/IP exception code 0A).
10.2 Supported Modbus Functions
The ETH-100 interface supports the Modbus TCP/IP function codes indicated in
Table 1.
Table 1: Supported Modbus TCP/IP Functions
Function Code Function Class
3 Read multiple registers 0
6 Write single register 1
16 Write multiple registers 0