Schedule Page
The Schedule page in the Maintenance Properties window indicates when the task is to occur. The location from which you open this Properties window determines the properties that are shown. The following table describes the properties that can appear on the Schedule page.
Property
Description
Schedule
The properties under this heading indicate when the task occurs. When you open the Maintenance Properties window for a task in the RBD Spares file, only the first three properties are shown.
Perform during maintenance only phases
Indicates whether the task is performed during maintenance-only phases when the block is part of a phase diagram. This checkbox is applicable only to phase diagrams. When it is cleared (default), the task is not performed during maintenance-only phases. When it is selected, the task is performed during maintenance-only phases. For more information, see Phase Diagrams.
Schedule maintenance
Indicates if the task is to occur only when triggered or at specified intervals. When this checkbox is cleared (default), the task is performed only when triggered. For more information, see Maintenance Triggers. In this case, the other properties in this area are unavailable. When this checkbox is selected, you can specify the maintenance interval to use. For more information, see Specifying an Interval for a Maintenance Task. When you open the Maintenance Properties window from a block’s Calculation Properties window, you can also use the properties under Optimize to calculate the optimal interval for this task. For more information, see Calculating an Optimal Interval for a Maintenance Task.
Maintenance interval
Indicates whether the optimal interval between performing the task is specified. To specify the amount of time between occurrences, you enter a value in this field. When you open the Maintenance Properties window from the RBD Spares file, Units is not shown. In this case, units are always calendar days. When you open the Maintenance Properties window from a block’s Calculation Properties window, if you leave the number signs (#.#) that appear by default, when you run RBD calculations, it is assumed that this task is not performed. However, if under Optimize, you select Local or Global for Optimization type, the optimal maintenance interval is calculated.
Units
The units for the specified maintenance interval. This property is not available when you open the Maintenance Properties window from the RBD Spares file because the units are always calendar days. Otherwise, it is available only when the interval is specified. Choices are:
Operating Days. When selected (default), the interval value is the operating age in days since the component was last switched on.
Calendar Days. When selected, the interval value includes both operating and non-operating (idle) times since the component was last switched on. If your system runs for only two weeks per month, the operating time is one half of the calendar time. You can specify whether results are to reflect system operating time or actual calendar time.
Optimize
The properties under this heading indicate whether the maintenance interval is optimized. This heading and its properties are shown only when you open the Maintenance Properties window from the Maintenance page in the block’s Calculation Properties window.
Optimization type
Indicates whether to calculate the optimal interval for performing the task. Choices are:
None. When selected (default), the number of days specified for Maintenance interval under Schedule is used.
Local. When selected, the next time RBD calculations run, the optimal interval is calculated in respect to only this block.
Global. When selected, the next time RBD calculations run, the optimal interval is calculated in respect to the entire system diagram. Both Minimum and Maximum become available so that you can specify the lower and upper limits to use when calculating the optimal interval.
Minimum
Specifies the lower limit (minimal interval time) to use for the optimal interval calculation. This property is available only when Global is selected as the optimization type. The default is 0.
Maximum
Specifies the upper limit (maximum interval time) to use for the optimal interval calculation. This property is available only when Global is selected as for Optimization type. If a value has not yet been entered, number signs (#.#) appear. In this case, it is assumed that no upper limit exists.
Optimized interval
Displays the result from the last optimization calculation performed. This property is display-only. If NA (for Not Applicable) is shown, the optimal interval has not yet been calculated.
Use optimized maintenance interval
Indicates whether or not to use the optimal interval calculated for the maintenance when RBD calculations are next run. This checkbox is selected and unavailable if None is selected for Optimization type. It is available when Local or Global is selected if the value for Optimized interval is either not NA or is greater than 0. In this case, when the checkbox is selected, the existing optimal interval value is used. When this check box is cleared, a new optimal interval is calculated based on currently specified parameter values and that value is then used.