In these cases, the PLC needs to have a gateway address set

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When configuring the IP address of a PLC’s Ethernet interface, under what circumstances does the PLC need to have a gateway address set? This article will explain it to you clearly! When a PLC only needs to communicate with devices on the same IP subnet, it is not necessary to set a gateway address. Changhui Instruments yunrun.com.cn When a PLC needs to communicate not only with devices on the same IP subnet but also with devices on other IP subnets, it is necessary to set a gateway address. The gateway address that needs to be set for the PLC is either the IP address of the router interface in its IP subnet, or the IP address of the VLAN interface in its VLAN. When a PLC communicates with devices on the same subnet, the data is sent directly to the device with the target IP address via the switch. When a PLC communicates with devices on different subnets, data is not sent directly to the device at the target IP address through a switch; instead, it is first sent to the device corresponding to the gateway IP address set by the PLC, that is, the router. The router then determines the route and forwards the data to the target device. Author: Feng Xuewei