PEI Schedule NID Calculation - Example

Schedule Next Inspection Date (or NID) is calculated based on the Horserace approach. This article aims to provide a detailed example of a NID calculation. Schedule NID [14] is determined as the soonest coming date (winner of the horse race) from a selection of dates that can be found on the Schedule Inspection event.

User Date

See [5]

• The user is allowed to set the User Date as any date in the future.

• The intent of the User Date is to allow the user to influence the Schedule NID for the first iteration of the Schedule.

Event Date

See [6]

• This date is coming from the linked Planned event, if one has been linked to the Schedule.

• Event Date will update automatically when the linked Planned event has its Event NID updated.

• Event Date is no longer shown here. It is now shown in the Details section and does not take part in the horserace for the NID.

RBI Next Insp. Date

See [7]

• This date comes from a completed RBI Analysis that may be linked to the Schedule via the Component.

• This date will be updated automatically when the RBI NID is updated. The Schedule will be set to Draft when that occurs.

Take note

To update RBI NID, the RBI engineer will need to apply a new inspection date through Inspection History.

Time interval

See [11]

• The Time interval [11] is calculated on recurring Schedules to allow the Time Interval Date [11] to be calculated.

• The Time interval [11] is determined as the lowest number of months from the following: User interval [8], Max interval [9], RBI Interval (MII) [10].

User interval 

See [8]

• Users are allowed to set the User interval [8] arbitrarily (up to 24000 months).

Max interval 

See [9]

• This interval is coming from the Inspection Default Settings and is selected based on the Hierarchy type, Schedule Inspection type and the Inspection reason.

RBI Interval (MII) 

See [10]

• This interval is coming from a completed RBI Analysis that may be linked to the Schedule via the Component.

• This interval will be updated automatically when the RBI MII is updated. The Schedule will be set to Draft when that occurs.

• RBI MII will not have an effect when Ignore RBI Interval/NID [2] is checked.

Time Interval Date 

See [12]

• This date is calculated based on the Last Insp. Date [4] (LID) and the Calculated Interval.

• Time Interval Date [12] must always be present on recurring Schedules.

• If the Schedule has not been created on an ECH or after approving a Corrosion Inspection, the Created Date [1] will replace the LID as the basis of the Time Interval Date calculation.
  

Calculated NID 

See [13]

• Applicable only on Corrosion Schedules.

• Calculated Interval and Calculated NID [13] are coming from the Corrosion Calc summary.

For more information on the Horserace calculations see PEI Next Inspection Date (NID) - Horserace