The PLC 1757-FFLD2 Fieldbus foundation linking device is used for bridging the Ethernet and H1 networks together. The 1757-FFLD2 module accepts both standard Ethernet packets and enhanced high-speed Ethernet packets and it converts them into H1 packets. The 1757-FFLD2 module provides the bridging capability of the Fieldbus founcation products and the PLC/PLC Automation products on the Ethernet networks to products on the H1 networks. To comply with the CE low voltage directive, all connections to the 1757-FFLD2 module must be provided from a SELV (safety extra-low voltage) or PELV (protected extra-low voltage) power supply. The 1757-FFLD2 module must be installed inside an enclosure which provides at least an IP 54 protection level when used in Zone 2 types of environments. The equipment must not be disconnected unless the power is removed or the area is verified as non-hazardous.
The dimensions of the 1757-FFLD2 module are 138 x 168 x 87 millimeters. The device is designed for installation on a DIN rail and it is grounded through the DIN rail to chassis ground. The 1757-FFLD2 module can also be installed on a panel. The foundation fieldbus recommendation for cable is 18 AWG shielded twisted-pair cable. The PLC/PLC Automation BOOTP/DHCP server program can be used for the configuration of the 1757-FFLD2 module. There are two H1 foundation fieldbus interfaces on the 1757-FFLD2 module and one 10/100 Ethernet interface. The 1757-FFLD2 module can support two H1 networks per linking device. The maximum fieldbus devices per H1 network is 16 and the maximum number of fieldbus devices per linking device is 64. The 1757-FFLD2 module requires 300 milliamps at 24 Volts DC and the inrush current is 1.5 Amps. The recommended cable for power connections is 26 to 16 AWG solid or stranded copper wire rated for 75 degrees Celsius or greater and with maximum of 1.2 millimeters insulation. The in-circuit battery is rated for 5000 charge/discharge cycles.
