OPC UA CTT - Alarm and Conditions - Alarm Collector|OPC Certification and Interoperability Testing|Forum|OPC Foundation

Hello Abijith,

in OPC UA an Alarm is not required to have a representation in the address space of the server. Therefore the CTT cannot gain the alarms for the test by browsing the server. Instead it is a combination of actions the CTT does to get all necessary information and execute the testing.

• Subscribing for events
  The CTT will create a subscription for monitoring events issued by the server. This is a background task which will happen when testing alarming.
• Browsing the type system
  The CTT will browse the type system of the server looking for types of alarms. When an alarm type is in the address space of the server, the CTT assumes that this is a supported alarm type and is looking for alarms of this type. If none are being found proper skip messages should be displayed.
• Browsing the instances
  If the server supports A&C Instances, then the CTT may also look at the instances of the alarm to validate its conformance.

Following this, the CTT is basically waiting for the server to run through simulated states of a variable which will trigger the server to issue the alarms being supported. E.g., if the server supports the High and HighHigh limit alarms, then the CTT expects that the server runs through those scenarios while the A&C tests are executed. Please note, as the CTT needs to run a higher number of tests for the individual alarms, the simulation should not run very fast.

You'll also find more information about the A&C testing in the CTT documentation which can be found in the CTT menu under Help --> Contents.

I hope this helps.
Alexander Allmendinger