# Alarms and conditions

<dl class="api-definition">
<dt>Concept</dt>
<dd><a href="/docs/development/opcua/server/alarms-conditions">Alarms and conditions</a></dd>
</dl>

| Type | Description |
|---|---|
| [OpcAcknowledgeableConditionNode](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcacknowledgeableconditionnode/) | Defines a condition node which introduces additional states for acknowledgement and confirmation. |
| [OpcAlarmConditionNode](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcalarmconditionnode/) | Defines an acknowledgeable condition node which introduces additional states to define active, suppressed and shelving alarm conditions. |
| [OpcConditionNode](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcconditionnode/) | Defines all general characteristics of a condition. |
| [OpcConditionRetainPolicy](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcconditionretainpolicy/) | Defines the evaluation policy for the [IsRetained](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcconditionnode/members#isretained) flag within the condition lifecycle. |
| [OpcDialogConditionNode](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcdialogconditionnode/) | Defines a condition node which represents itself as a dialog. |
| [OpcDiscreteAlarmNode](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcdiscretealarmnode/) | Defines an alarm condition node which is used to classify types into alarm conditions where the input for the alarm may take on only a certain number of possible values (e.g. true/false, running/stopped/terminating). |
| [OpcExclusiveLimitAlarmNode](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcexclusivelimitalarmnode/) | Defines an alarm condition node with multiple mutually exclusive limits. |
| [OpcLimitAlarmNode](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opclimitalarmnode/) | Defines an alarm condition node with multiple limits. |
| [OpcNodeManager](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.server.opcnodemanager/) | Provides an abstract base class used to organize and maintain the address space or only a part of it. |
| [OpcNonExclusiveLimitAlarmNode](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcnonexclusivelimitalarmnode/) | Defines an alarm condition node with multiple non-exclusive limits. |
| [OpcOffNormalAlarmNode](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opcoffnormalalarmnode/) | Defines an alarm condition node intended to represent a discrete condition that is considered to be not normal. |
| [OpcServer](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.server.opcserver/) | Represents an OPC UA server which provides the address space defined by its [NodeManagers](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.server.opcserver/members#nodemanagers) to its clients. |
| [OpcTripAlarmNode](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.opctripalarmnode/) | Defines an alarm condition node which is intended to represent an equipment trip condition. |