This new feature allows controlled access to both control and configuration data, thus adding another level of security. Configuration of the IP filter is facilitated by means of Web pages in the controller. When the security option is switched on, only certain nodes can communicate with the 750-841. These communication parametersare established via a list of trustworthy devices, stored directly in the controller. Based on the IP address and port number transmitted by the device, the controller can identify whether or not to send or receive information from that device. The 750-841 also features a multitasking 32-bit CPU with a real-time clock, 512 kbytes of program memory, 128 kbytes of data memory, and 24 kbytes of retentive memory. Besides supporting Modbus/TCP, Modbus/UDP, and EtherNet/IP network protocols, the controller also supports several Ethernet protocols for system management and diagnostics such as HTTP, BootP, DHCP, DNS, SNTP, FTP, SOAP, SNMP and SMTP.
Wago Corp.,, N120 W19129 Freistadt Rd., Germantown, WI 53022, (800) DIN-RAIL, www.wago.com