Read/Write data from Omron (NJ501-1400) PLC into node-red

Industrial
1

Hi,

I need to connect Omron (NJ501-1400) PLC with the node-red. Is there some node (like node-red-contrib-s7 for Siemens PLC) to communicate with the Omron PLC ? What could be the most suitable way to establish connection?

Thanks in advance!

2

Try using the forum search ( the magnifying glass) for the word "Omron"

3

Depending on the firmware level and version of NJ, you may well have OPCUA built in.

If so, I'd recommend using the IIOT nodes.

If not, then there isn't a great deal of FINS or EtherNet/IP type nodes I'm afraid.

You could always use write some ladder with socket services in the PLC and use the TCP nodes as a last option.

2 other options...
1.
There are some MQTT function blocks available for the NJ / NX PLCs. I've used them and they work.

The NJ PLC is a mighty fast PLC and it would be capable of running logic to implement MODBUS TCP. There may be some

4

Some links...

Modbus...
https://www.myomron.com/index.php?action=kb&article=1245

MQTT...
take a look at this project. It has MQTT Client connect, pub and sub FBs in a library.

5

Thanks you very much for the detailed answer. I will see and try different options!

6

Hi Steve,

Today i read and write some tags from/to Omron (NJ501-1400 Firmware version 1.19) by using node-red-contrib-opcua node through OPC UA. It works for me.

1 Like
7

Glad I could help.

To help others in the future, it would be really good if you could indicate which node(s) you used, maybe export & post a an example flow and perhaps even some screenshots?

Cheers, Steve.

1 Like
8

Hello,
Im trying to make connection between Omron NJ501-1400 and rasberry pi trough Node-Red
node-red-contrib-opcua node. But I have some problems with certificates. OPC UA server from PLC keep rejecting client certificate. Have you solved this? Or can you give me an advice how to do that?

9

@Ondrej I cant help you on the OPCUA certificate issue but if you are needing to get data from the PLC, you could try using FINS...

10

I must also add - for the NX and NJ series PLCs you might be better off using MQTT directly.

There are FBs (Function Blocks) available for...

  • reading and writing JSON
  • publishing and subscribing to MQTT

Of course I must also point out that going down the MQTT route requires you to add FB libraries and LADDER/ST to the PLC in order to generate the MQTT messages - whereas the OPCUA/FINS method requires no ladder to read/write values.

I use both methods depending on the situation.

11

As far as I remember, this P/N has Ethernet/IP protocol built in, if yes you can simply use the https://flows.nodered.org/node/node-red-contrib-cip-ethernet-ip node

12

This topic was automatically closed 60 days after the last reply. New replies are no longer allowed.