OPC-UA "node-red-contrib-opcua" v0.2.316. HOW to use it in "SUBSCRIPTION” mode

Hello everyone,
I am using a Raspberry Pi 4 with Node-RED v3.1.0 and "node-red-contrib-opcua" v0.2.316.

I have an OPC-UA industrial device with the endpoint: "opc.tcp://". Currently, I can request individual parameters or an array of data by sending a topic 'ns=3;i=1758028' to the "Opc-Ua-Client-node."

However, this requires me to request the parameters from the device each time, at most with a frequency of once per second.
I can't figure out if there's a way to use the “SUBSCRIPTION” mode intead of “POLLING” mode, to subscribe to my device so that I can automatically receive data whenever it changes.

I'm unable to determine which nodes from the Office library “node-red-contrib-opcua” v0.2.316 I should use and how to set it up to automatically receive the data with subscription mode .
I am 100% certain that my device can send data through a subscription mode.

Many thanks in advance.

Subscription is based on change on value or status. Read is used to poll data.
Could it be that you inject timestamp that is then used as publish interval.
Try to inject empty string.. haven´t seeing your flow this is pure quess.

With or without payload or topic in the Inject node, I receive the same error showed in the image.

With topic with that send a string "a" in the Inject node, I receive KEEPALIVE from the "OpcUa-Client Node" but no data receive even if value on devices changes... ad receive Error [{}]

Any Idea?

Please look first examples: OPCUA-TEST-NODES.json you have totally wrong flow...

Thanks Sir,
I'm able to subscribe and receive value with the flow in the image...

I can understand that I can SUBRSCIBE just ONE opc-Ua TAG... is it correct?

If I inject the topic with the single TAG, I can subscribe and receive data, but If I need to subscribe more topic, how can I do this?

If I add anothe OpcUa-Client node, I receive error "Client disconnected & closed: connection error error: Error: BadTooManySessions (0x80560000)""

Just inject multiple opcua-items to client node with subscribe mode.

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