Block Details

The Block Details worksheets for simulation diagrams display the details for each block, or component, in the system. Click the name of the block in the navigation panel to display the block details for that block on a separate worksheet. The values shown are averages of the results of all of the simulations.

Note: You can customize the order in which the blocks are displayed in the simulation results by right-clicking inside the diagram sheet and choosing Set Block Order on the shortcut menu. You will need to resimulate the diagram for the new block order to be shown in the results.

  • General Information
    • Mean Availability (All Events): The mean availability of the block during the simulation.
    • Mean Availability (w/o PM, OC & Inspection): The mean availability of all downing events for the block, not including preventive, on condition or inspection tasks, during the simulation.
    • Block Uptime: The total amount of time that the block was up (i.e., operational) during the simulation.
    • Block Downtime: The total amount of time that the block was down (i.e., not operational) during the simulation.
    • Diagram ID: The ID of the diagram the block is in. This result is shown only if Display Object IDs is selected on the Other Common Settings page of the Application Setup.
    • Block ID: The ID of the block (assigned to the block when it is created). This result is shown only if Display Object IDs is selected on the Other Common Settings page of the Application Setup.
  • Metrics
    • RS Criticality Indices
      • RS FCI: The ReliaSoft Failure Criticality Index for the block. This is a relative index showing the percentage of times that a failure of the block caused a system failure (i.e., the number of system failures caused by the block divided by the total number of system failures). Note that this relates only to failures; it does not include every event that could bring the system down (such as routine maintenance).
      • RS DECI: The ReliaSoft Downing Event Criticality Index for the block. This is a relative index showing the percentage of times that a downing event of the block caused the system to go down (i.e., the number of system downing events caused by the block divided by the total number of system downing events).
      • RS DTCI: The ReliaSoft Downtime Criticality Index for the block. This is a relative index showing the contribution of the block to the system's downtime (i.e., the system downtime caused by the block divided by the total system downtime).
      • RS BCCI: The ReliaSoft Block Cost Criticality Index for the block. This is a relative index showing the contribution of the block to the total costs (i.e., the total block costs divided by the total costs).
    • Block Downtime Contribution Index This is an index showing the factors contributing to the block downtime. Both a team and a spare part pool must be defined for this to return meaningful results.
      • Active Maintenance CI: A relative index showing the contribution of repair/inspection time to the block's total downtime (the ratio of the time that the team is actively working on or inspecting the item to the total downtime). In previous versions, this result was called "Non-Waiting Time CI."
      • OFF by Trigger CI: A relative index showing the contribution of OFF event times to the block's total downtime. An OFF event is when the block is turned off by state change triggers.
      • Total Waiting Time CI: A relative index showing the contribution of wait factor times to the block's total downtime (the ratio of downtime not including repair/inspection time to the total downtime). Wait factors include crew wait times, task wait times and spare part wait times.
      • Waiting for Opportunity CI: A relative index showing the contribution of time spent waiting for repair opportunity to the block's total downtime. Time waiting for opportunity is the time that elapses before the start of any task that leads to the block being restored, such as time before a scheduled inspection that triggers a corrective task.
      • Team/Parts Wait Ratio: The ratio of the team delay (crew availability + crew logistic delay + team assembly time) to the part delay. A value of 100% means that both waits are equal. A value greater than 100% indicates that the team delay was in excess of the part delay. For example, a value of 200% would indicate that the wait for the team is two times greater than the wait for the part.
    • Summary Metrics
      • MTBF (Total Time): The mean time between failures for the block during the simulation. This is calculated by dividing the simulation run time by the block's number of failures.
      • MTBF (Uptime): The mean time between failures for the block considering only the block uptime.  This is calculated by dividing the block’s uptime by the number of failures.
      • MTBE (Total Time): The mean time between downing events for the block during the simulation.  This is calculated by dividing the simulation run time by the block’s number of downing events.
      • MTBE (Uptime): The mean time between downing events for the block considering only the block uptime.  This is calculated by dividing the block’s uptime by the number of downing events.
      • MTTM:  The mean time to maintain for the block. This is calculated by dividing the block's downtime by the number of downing events (i.e., the mean duration of downtime events for the block during the simulation).
      • MTTR: The mean time to repair for the block. This is calculated by dividing the total downtime associated with corrective tasks for the block by the number of failures.
  • Downtime Summary
    • Active Maintenance Time: Time that the block was undergoing active maintenance/inspection.
    • Total Waiting Time: The functional total time that the block spent waiting for maintenance/inspection to begin (Block Downtime - Active Maintenance Time - Off by Trigger time).
    • Waiting for Opportunity: The total downtime for the block due to task scheduling (i.e., time that elapses before the start of any task that leads to the block being restored, such as time before a scheduled inspection that triggers a corrective task).
    • Waiting for Crews (Availability): The total downtime for the block due to crew conflict times. Per task performed, this is calculated as an average of the crew conflict times for the entire team.
    • Waiting for Crews (Logistic): The total downtime for the block due to crew logistic delay times (i.e., time spent waiting for a crew due to logistic delay). Per task performed, this is calculated as an average of the crew logistic delay times for the entire team.
    • Waiting for Team Assembly: The total downtime for the block due to time the crews spent waiting for all other crews in the team to arrive. This time starts once each crew is ready to work on the task (i.e., after any logistic delay). Per task performed, this is calculated as an average of the crew waiting times for the entire team.
    • Waiting for Parts: The total downtime for the block due to spare part wait times. If no spare part pool is defined then this will return zero. Note that this reflects the entire spare part arrival time, not just the portion remaining after the team has arrived (unlike the value shown in the Crew Details worksheet).
  • Event Count Summary
    • Block Failures
      • Number of Failures: The total number of failures that occurred during the simulation for the block.
      • Number of System Downing Failures: The number of failures for the block that caused the system to go down during the simulation.
      • Failure Downtime: The total amount of time that the block was down (i.e., not operational) due to failures during the simulation.
    • For each of the four classes of tasks (i.e., corrective, preventive, on condition and inspection), the following information is presented with regard to tasks performed during the simulation time:
      • Number of [Task Class]: The total number of tasks of this class performed on the block during the simulation.
      • [Task Class] Downtime: The total amount of time that the block was down (i.e., not operational) due to tasks of this class during the simulation.
    • State Change Triggers
      • Number of OFF Events by Trigger: The total number of events where the block is turned off by state change triggers. An OFF event is not a failure but it may be included in system reliability calculations.
      • OFF by Trigger Time: The total amount of time that the block was OFF due to state change triggers.
    • Total
      • Number of Block Downing Events: The total number of downing events that occurred during the system simulation time for the block.
      • Number of System Downing Events: The number of events for the block that caused the system to go down during the simulation.
  • Cost Summary
    • For each of the four classes of tasks (i.e., corrective, preventive, on condition and inspection), the following information is presented with regard to costs that accrued during the simulation time:
      • Misc. Costs: The miscellaneous costs associated with the task class. This is based on the cost per task and downtime rate, specified in the Maintenance Task window.
      • Costs for Parts: The cost for spare parts due to tasks of this class. This is based on the direct cost per item as specified in the Spare Part Pool window, as well as any indirect costs (e.g., holding costs, costs associated with restocking, etc.). Note that this value is not available for inspection tasks, as inspections do not use spare parts.
      • Costs for Crews: The cost for crews due to tasks of this class. This is based on the direct cost per unit time and cost per incident, as specified in the Crew window.
    • Costs (Consequential)
      • Block Failure Cost: The block failure costs that accrued during the simulation time. This is based on the block's number of failures multiplied by its cost per failure, as specified in the Block Properties window.
      • Block Downtime Cost: The block downtime costs that accrued during the simulation time. This is based on the block's downtime multiplied by its downtime rate, as specified in the Block Properties window.
      • Block Uptime Cost: The block uptime costs that accrued during the simulation time. This is based on the block's uptime multiplied by its uptime rate, as specified in the Block Properties window.
      • Total Block Consequential Cost: The sum of the Block Failure Cost, the Block Uptime Cost and the Block Downtime Cost.
    • System Level Contribution
      • System Level Failure Cost (CM): The contribution of this block to the system level failure costs due to failure events. This is calculated using the overall system level failure costs (CM) multiplied by the ratio of the number of times this block caused a system failure to the total number of system failures.
      • System Level Downtime Cost (CM): The contribution of this block to the system level downtime costs. This is calculated using the overall system level downtime costs (CM) multiplied by the ratio of the system downtime caused by this block to the total system downtime.
      • System Level Total Costs (CM): The sum of the System Level Failure Cost (CM) and the System Level Downtime Cost (CM).
      • System Level Failure Cost (Total): The contribution of this block to the system level failure costs due to downing events. This is calculated using the overall system level failure costs (total) multiplied by the ratio of the number of times this block caused a system failure to the total number of system failures.
      • System Level Downtime Cost (Total): The contribution of this block to the system level downtime costs due to downing events. This is calculated using the overall system level downtime costs (total) multiplied by the ratio of the system downtime caused by this block to the total system downtime.
      • System Level Total Costs (Total): The sum of the System Level Failure Cost (Total) and the System Level Downtime Cost (Total).
    • Block Opportunity Costs
      • Block Opportunity Cost (Total): The loss of throughput and revenue attributed directly to this block due to downing events. This is calculated by multiplying the total system opportunity costs (shown in the System Costs worksheet) by the block DTCI.
    • Block Total Costs
      • Block Total Cost: The total cost associated with the block, including all costs for all task types, the Total Block Consequential Cost and the System Level Total Costs. Note that the Block Opportunity Cost is not included in this value.
  • Throughput Analysis Summary: Throughput results will be calculated only if you selected to run a throughput simulation on the Analysis Settings page of the diagram control panel.
    • Throughput
      • Throughput: The total number of units that were processed/produced by the block during the simulation time.
      • Excess Capacity: The additional number of units the block could have processed/produced during the simulation.
      • Backlog: The total number of units that were backlogged (i.e., waiting to be processed) for the block at the end of the simulation time. This is based on whether the block can accept a backlog and how the units were allocated, as specified in the Block Properties window.
      • Backlog Processed: The total number of units that were backlogged but eventually processed by the block during the simulation time.
    • Throughput Metrics
      • Maximum Uptime Capacity: The maximum number of units the block could have processed/produced while it was up during the simulation.
      • Uptime Utilization: The percent of units the block actually produced/processed of what it could have processed/produced while it was up during the simulation. (i.e., the ratio of the block throughput and the block maximum uptime capacity.)
      • Maximum Capacity: The maximum capacity of the block, which is the maximum number of units the block could have processed/produced during the simulation.
      • Actual Utilization: The percent of units the block actually produced/processed of what it could have produced/processed (i.e., the ratio of the block throughput and the block maximum capacity).

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