Calendars provide optimal control over the working time of every element in your simulation.

Calendars (with the exception of the main calendar – see below) can be applied to one or more Activity or Start Point. An Activity / Start Point can have one calendar applied to it.

Main Calendar

The main calendar applies to the whole simulation and can be used in conjunction with the main simulation clock to configure your exact simulation working time requirements.

Active Vs Blocked Calendars

There are two key types of calendars, Active and Blocked.

Times that you add to an active calendar represent times ‘working times’. For example, if you were to add no time periods to an active schedule and then apply it to an Activity then that would be equivalent of saying that the Activity is never active / working.

A blocked calendar is simply the opposite of active. It presumes that all times are working times and any times you add to the calendar are treated as ‘blocked out’ times or ‘non working’ times. For example if you where to setup a recurring event for Friday afternoons and apply it to an Activity, this would be equivalent of saying that the Activity does not work on Friday afternoons.

Simulation Start Date

By default SIMUL8 runs from the first day (Monday) of the current week for the specified time (results collection period + warm up time). However you are able to specify any simulation start date from the Calendars dialog, by checking the ‘Base simulation time on date scale’ box and selecting the required date from the date box.

Calendar Creation / Modification

Creating , deleting, copying and editing calendars, can all do done through the Calendars dialog on the Data & Rules tab, using the New, Erase,Copy and Properties buttons respectively.


The 'on shift' and 'off shift' text beside the calendar relates to the calendars current state. For example if Calendar 2 contains a single recurring event (see below) that works 9-5 every Monday, and the current simulation time is Monday 3pm then the text in the square brackets would report ‘on shift’, however if the current sim time was 3pm on a Wednesday (or any other day than Monday) then the calendar would be ‘off shift’.

After Clicking ‘New’ to create a new Calendar you will be presented with the ‘Calendar’ dialog, from this dialog you can do various things:

  • Set the Calendar to be the main calendar (by using the ‘Main Calendar’ checkbox)
  • Set the Calendar to be an Active or Blocked calendar (by using the Active/Blocked radio buttons)
  • Apply the calendar to Work Centres and Work entry points (by using the Checkboxes in the central list box). Note: Activities and Work entry points that already have a calendar applied to them will appear and be disabled.

calendar.jpg_nolink Clicking ‘Manual Add’ allows you to add new events, see Single and Recurring Calendar events sections below.

Single Calendar Events

Single calendar events allow you to specify a single block out or active time (depending on your calendar setting). Simply specify a start date and time and an end date and time, for example, you may wish to block out a bank holiday date, let’s say Christmas Day. If you had a 9-5 working day your entry would look like this:


Recurring Calendar Events:

Recurring calendar events provide a powerful and quick way of setting up calendar entries. Effectively a recurring calendar event automatically creates multiple single entries for you.

  • Timing:
    • Start: The starting time of the recurring event
    • Duration: The length of the event in simulation time units
    • End: The ending time of the recurring event. Note: This is a non editable box and will is automatically updated when the duration time is changed.
  • Recurrence pattern:
    • Here you can choose what the type of recurrence you require: Daily, Weekly, Monthly or Yearly. For each recurrence type you can specify what days or dates the event should occur.
  • Range of recurrence:
    • Start:
      • Simulation start date: checkbox: Having this checked will always using the ‘Simulation Start Date’.
      • If you uncheck the Simulation start date checkbox you are free to select your own starting date from the date dropdown to the right.
    • End:
      • No end date: If this radio option is checked it is effectively equivalent of saying the event will occur from the given start date until the end of the simulation.
      • End After: If the radio option is selected then you are free to specify the number of occurrences that the event should occur for.
      • End by: When this radio option is checked you are free to select a date

For example the below recurring dialog shows a recurring event that would occur for the full day (9-5) for every day except Wednesdays, Saturdays and Sundays. If this entry belonged to an active schedule that was applied to a single Activity then this would be equivalent of saying that the Activity works every week day except for Wednesdays (and it doesn’t work weekends).


As many single and recurring events as you wish can be added to a calendar, this allows complex powerful and flexible calendars to be built and applied in a short time frame.

Visual Logic Commands

Event roll over / rolling events (advanced single event example)

If your clock is a 9-5 day (8 hours = 480 minutes) per day, and you set up an event to happen at 9 am on Monday morning, and you set the event duration to 960 minutes. Because 960 minutes is more working time than in a day (480 minutes more), this extra time rolls over to the beginning of the next working day. So, in effect the event described above is actually working a full day Monday and Tuesday, or equivalent of having two 480 minute duration events for Monday and Tuesday both starting at 9 am.