Timer Start Event

Element
Description	A Timer Start Event allows you to start a BPMN model after a defined cycle or at a defined time. Every time the timer is triggered, the model will be started.
Attributes	Name Description Timer (see Particularity) Symbol Type
Particularity	A start event can only be created via the elements toolbar. Another particularity of the Timer Start Event is the attribute Timer which is available in the Attributes Panel: To define the timer settings, click Open Timer to open the timer editor. For detailed explanations see How to Use the Scheduler/Timer.
Execution	On Event: Without input or output parameters.
Editing and Styling	Refer to Working with the BPMN Editor for further information regarding editing of BPMN elements using the different context menus on the diagram pane. Refer to Styling BPMN Elements for further information regarding styling possibilities for BPMN elements, for example how to change the background color, the font style and size etc.

How to Use the Scheduler/Timer

If you use option Open Timer in the attribute panel, a separate editor will open where you can define the settings of your Timer Start Event. You have two options with different settings:

Scheduler (see below)
Timer (see below)

Scheduler

Use the scheduler if you want to define a pattern for your Timer Start Event, for example to start the model every monday, every hour etc.

Setting	Description	Default
Allow Parallel Executions	If checked, each time a scheduler pattern matches, the scheduler activity diagram is executed - even if another execution is already running. If not checked, the next execution cycle is suppressed if an execution diagram is already being run.	Checked
Year(s)	Insert a positive integer or a pattern.	*
Month(s)	Use numbers 1 to 12 or a pattern.	*
Weekdays(s)	Valid input: Mon or Monday Tue or Tuesday Wed or Wednesday Thur or Thursday Fri or Friday Sat or Saturday Sun or Sunday a pattern	*
Day(s)	Depending on the month, valid input are numbers from 1 to 31 or a pattern.	*
Hours(s)	Use 0 to 23 or a pattern.	*
Minute(s)	Use 0 to 59 or a pattern.	0
Seconds	Use 0 to 59 or a pattern.	0

Timer

Select the timer if you want to define a cycle for example to start the model after one week, after two hours etc.

Setting	Description	Default
Repeat Interval	Enter a valid time duration expression (see below). Refer to Time Durations for detailed information. This setting defines the time interval between two calls of the timer action.	-
Occurences	Insert a positive integer to define the count of repetitions. If you want the timer to be endless, check Always (default).	Always
First Occurence	Enter a valid time duration expression (see below). Refer to Time Durations for detailed information. This setting defines the wait interval after service start before the timer is executed for the first time.	0 seconds

Duration Expression Wizard

The settings Repeat Interval and First Occurrence contain option Edit. Click this option to open a wizard that supports you to define the necessary duration expression:

Insert positive integers in the desired fields. The result is shown below. Click Save to close the wizard:

The duration expression is displayed in the corresponding field:

Once you are familiar with the notation of the duration expression, you can also insert it directly in the field.

BPMN_Start_Event_Example

Click here to download a simple example model that shows what you can do with Start Events in Scheer PAS Designer.

Related Pages: