Industrial Engineer · phase 5 of 16
IP Address / Subnet Mask
Network settings that identify an Ethernet device and determine which addresses are locally reachable.
The Explain card
- Plain English
- The IP address is a device's number on an Ethernet network, and the subnet mask says which part of that number identifies the network and which part identifies the device. Two devices can talk directly only if the mask puts them on the same network.
- Example
- A drive on the plant network with a mask that fixes the first three numbers can reach any device whose first three numbers match its own. A typo in the mask makes the PLC unreachable while every link light stays green.
- Why it matters
- Duplicate addresses and wrong masks produce intermittent faults that look like bad cables. Keep a written address list for every panel and check it before you plug anything in.
- Hook
- The number on the door and the name of the street.
Where it sits in the deck
Phase 5: PLC Industrial Communications
The protocols that let controllers, drives and operator panels talk, plus the addressing and description files that make them agree on what was said.
