Hello.

I think that with such low number of items, you can stay subscribed permanently.

In similar scenarios in the past, however, our users have usually combined the subscriptions (to monitor the “trigger” tags) and “one-shot” reads (ReadItem, ReadMultipleItems) performed only when the trigger condition has been satisfied. This seems to conform more with the underlying logic. But you may have other reasons to subscribe to all items.

Regards

Zbynek Zahradnik

From: P.
Sent: Wednesday, March 14, 2012 10:14 PM
To: Zbynek Zahradnik
Subject: Re: OPC.net question

Zbynek

[.....]. Considering that I only need to monitor around 30 values, does it matter if I subscribe to all values permanently or is it better practice to unsubscribe when some of them are not required? The reason I ask is that some of the variables are Boolean status bits and in reality I only need to read the analogue values when the booleans are true.
Regards

P.