Omron NB/NA — 'PLC No Response' (FINS Node & Subnet)

Omron · intermediate · 25 min

An Omron NB or NA HMI that can't reach the PLC usually has a FINS node-address or subnet mismatch. Match the node address to the IP's last octet, put both on the same subnet, then power-cycle the PLC.

ℹ️ Omron Ethernet uses a FINS node address alongside the IP. If the node address and IP don't line up on both ends, the panel gets 'no response' even with correct-looking IPs.

Why an NB/NA panel can't connect

On an Omron NB (NB-Designer) or NA (Sysmac Studio) HMI, a 'PLC No Response' / not-connected condition to an Omron PLC (CP/CJ/NJ/NX) is almost always a FINS node-address or subnet mismatch, not a dead panel. Omron Ethernet identifies each device by both an IP address and a FINS node address, and the two must agree on both ends.

Match the FINS node address

1. NB-Designer side: set the node address of the PLC/HMI to the last octet of its IP address, and after changing it, check the communication settings actually updated.
2. Sysmac Studio / PLC side: open Built-in EtherNet/IP Port Settings and verify the FINS node address. If automatic generation is used, the node address is the last octet of the IP — so the panel's configured PLC node must match that.

If the panel points at the wrong FINS node (or the PLC's node doesn't equal its IP's last octet as the panel expects), you get no response even though pings might look fine.

Subnet and IP table

• Confirm the HMI IP and PLC IP are on the same subnet. If they must be on different subnets, you have to add entries to the IP address table so FINS can route between them.
• Check for IP conflicts and correct cabling to the right Ethernet port.

After changing settings — power-cycle the PLC

A very common fix: after transferring the settings to the PLC, completely power the PLC OFF, then back ON. Omron Ethernet/FINS settings often need a full PLC restart to take effect — a warm change alone can leave the old parameters active.

USB (for transfer/diagnosis)

If you can't even transfer to the panel over USB, confirm the OMRON USB driver is present — open Device Manager and look under Modems for the OMRON USB driver; reinstall it if it's missing or errored.

Step-by-step

1. Match the FINS node address to the IP's last octet on both the panel (NB-Designer) and the PLC (Sysmac Studio Built-in EtherNet/IP Port Settings).
2. Same subnet — or add IP-address-table entries if routing across subnets.
3. Transfer settings, then power-cycle the PLC completely (off, then on).
4. USB issues: verify the OMRON USB driver in Device Manager (under Modems).
5. Re-test communication and confirm the panel connects.

Verify

Once the FINS node and subnet match and the PLC has been fully restarted, the panel connects and tags update. If 'no response' persists, re-check the FINS node address on both ends — it's the setting a healthy ping doesn't validate.