How-To
Network How-To
Network How-To in industrial control systems — covering 5 topic areas in the CurryControls.com controls and automation knowledge hub.
Written guides in this section
Full references, procedures, and diagnostic guides published under Network How-To.
How to Assign IP Addresses on a Control Network
Build an addressing plan before the first device is configured: one subnet per zone and site, a fixed block layout so an address says what the device is, static addresses on everything that controls a process, and a schedule that is kept current.
9 min readUpdated Sep 5, 2026
How to Configure VLANs on a Control Network
Turn a zone plan into switch configuration: a VLAN per zone with its own subnet, access ports for devices, tagged trunks between switches, a native VLAN that carries nothing, a separate management VLAN, and routing between VLANs only through the firewall.
10 min readUpdated Sep 5, 2026
How to Troubleshoot an Ethernet Connection
Work an Ethernet problem one layer at a time: link light and cable, then speed, duplex, and VLAN on the switch port, then address, mask, and gateway, then the application port through the firewall. Each layer has a one-minute test that rules it in or out.
10 min readUpdated Sep 5, 2026
How to Test Fiber
Test a fiber link at acceptance and at fault: inspect and clean every connector, measure end-to-end loss with a light source and power meter in both directions and at the operating wavelengths, and record everything with the fiber schedule.
8 min readUpdated Sep 5, 2026
How to Diagnose Packet Loss
Find where and why frames are dropped: measure loss with a continuous ping, localize it hop by hop from both directions, read the port counters on the path, and match the pattern to its cause: a cable, a duplex mismatch, congestion, a loop, or a radio link.
10 min readUpdated Sep 5, 2026
Topics in this area
Assign IP Addresses
Assign IP Addresses — practical reference notes for controls engineers, integrators, and technicians working with network how-to.
Configure VLANs
Configure VLANs — practical reference notes for controls engineers, integrators, and technicians working with network how-to.
Troubleshoot Ethernet
Troubleshoot Ethernet — practical reference notes for controls engineers, integrators, and technicians working with network how-to.
Test Fiber
Test Fiber — practical reference notes for controls engineers, integrators, and technicians working with network how-to.
Diagnose Packet Loss
Diagnose Packet Loss — practical reference notes for controls engineers, integrators, and technicians working with network how-to.
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