This topic describes the calculations used by the gadgets you add to dashboards in iMonitor Designer and the filters each gadget/gauge supports.

Active batch average dwell time

Looks at the most recent x number of units processed at the specified operation alias for the batch (x is configurable, the default is 10). The next operation in the flow for the active batch is determined. For each unit, an attempt is made to locate a WIP record for the same serial number at the next operation. If found, the Time Completed at Operation 1 is subtracted from the Time Started at Operation 2 for that same unit and the difference is stored. If not found, that unit is skipped and the process is repeated using the second most recent unit to leave Operation 1. The process continues until x calculations are completed successfully or the algorithm runs out of Operation 1 WIP records. The average of all x differences is returned.

Active batch effective time per unit

Subtracts the Time Started of the very first WIP record at the operation for the active batch from the Time Completed of the most recent WIP record for the same operation, then divides that result by the total number of WIP records for the batch at the operation. The result is the average production rate across the whole job, including any down time related to breaks or other reasons.

Active batch units per hour

Subtracts the Time Started of the second most recent WIP record for the active batch at the operation from the Time Started of the most recent WIP record for the active batch at the operation. Takes the result (snapshot time per unit) and applies this formula to convert to units per hour. Units per Hour = 3600 / (snapshot seconds per unit).

Active job components per hour

Looks at all units processed and sums components placed and sums actual cycle time from the ItemSummary table to formulate components per hour. Components per hour = (total components placed / total cycle time) * 3600.

Average cycle time

Averages the cycle time of the most recent x number of units for the active batch for the point (x is configurable, default is 10). Cycle Time for a pair of units is defined as (Time Unit 2 Entered Point) – (Time Unit 3 Work Start at point). The calculation uses the Time Started field of the ItemSummary table.

Average working time

Averages the cycle time of the most recent x number of units for the active batch for the point (x is configurable, default is 10). Working Time for a single unit is defined (Time Work Complete at point) – (Time Work Start at point). For browser WIP records, TimeWorkStart is the same as TimeStarted and TimeWorkComplete is the same as TimeCompleted. For xLink machine data, this is not necessarily the case, it could be that a machine completes work on a unit, but because it is blocked by a downstream machine, it does not leave the machine for another minute or two.

Active batch completion duration

An estimate of the time it will take to complete the job at the selected Operation and not to complete the entire route of the batch.

Determines the number of needed units for the Operation (job quantity – distinct WIP count) + scrap overage. This determines the production rate. If the Time Standard option (default) is set to Real-Time the production rate is calculated from the average cycle and will look at the last 10 units processed. If you select Estimated Time, the production rate is calculated from the estimated cycle times. The final calculation is the product of the production rate and the total units needed.

Job processing time detail

Displays the serial number, processing time and target time of x number of units processed or in process for all operations of the active batch (defaulted to the top 5 most critical units). Processing Time represents the actual cycle time and also includes the current processing time of any unit started and has not yet been completed. Target time is the estimated cycle time from the Time Standards. The most critical units are the ones with the least time remaining. The key idea behind this output is to show that the time processing is going beyond the time it should take to process. The gauge can be set to show only the active unit which displays only one unit which is the most critical.

Active job completion

Subtracts the number of units that have failed from the number of units processed through the operation to derive at the number of completed units. If the number of completed units is greater than the job quantity, the completed quantity is reduced to the job quantity.

Active Job DPMO (IPC 9261)

Calculates defects per million opportunities at the operation level. IPC 9261 DPMO is (the total defects collected / (the unit count * the operation opportunities) ) * 1,000,000.

Active Job DPMO (IPC 7912)

Calculates the defects per million opportunities, at the assembly level. IPC 7912 DPMO is (the total defects collected / (the unit count * the assembly opportunities)) * 1,000,000.

Active Batch Defects Per Unit (DPU)

The DPU is the total defect count / the total unit count (configurable to use x number of the most recent units).

Pass Yield

Configurable to use first pass, or second pass yield. Pass yield is calculated using pass unit failures. First pass failures are units that have ever failed and second pass failures are units that have ever been failed more than once. Pass yield is calculated as ((total units – total failed) / total units) * 100.

Overall Equipment Effectiveness (OEE) overview

• Availability is the percentage of the planned time that a machine is available. It is a measurement of uptime that is designed to remove the effects of scheduled downtime, quality and performance.

• Performance is the percentage of the designed speed at which the machine is running. It is a measurement of speed that is designed to remove the effects of availability and quality.

• Quality is the percentage of the planned total units produced. It is a measurement of yield that is designed to remove the effects of availability and performance.

Each of these calculations produces a value between zero and one. When this information is displayed, it is usual for this value to be multiplied by one hundred and presented as a percentage value.

Overall Equipment Effectiveness (OEE)

The product of OEE Availability, OEE Performance and OEE Quality.

OEE Availability

This value reports the percentage of up-time achieved during planned production time during a specified time window. Planned production time is considered all time within the specified time window if zero planned production times have been defined. If one or more planned production times have been defined then the total planned production time is the time within the specified time window that has been explicitly identified as being production time.

Operating time is calculated by reviewing machine state information for the planned production time window and summing up the duration of each machine state which is designated as operating time. The designation of a machine state as operating time or not is achieved in the FactoryLogix Analytics iMonitor Settings area.

If no machine state information is recorded within the planned production time window the last known machine state value shall be used. If no machine state information has ever been recorded for the operation then the operating time shall equal the planned production time window.

In iMonitor you can determine Operating Time using reason code information instead of machine state information. A reason code is assigned to a machine state record by an operator. As a result, every time a new machine state is recorded, an operator must assign a reason code (through the UI) before that change in machine state can be used to determine operating time.

Consider a situation where a machine state is recorded and the operator assigns a reason code that isn't considered operating time. From the time associated with that machine state record forward no further changes in machine state have had a reason code assigned. All time from the last machine state record with a reason code forward will be treated as operating time—or not—depending on whether the reason code is considered operating time. Reason codes are historical by nature. We do not recommend using reason codes when creating dashboards to display OEE information.

For an Operation Group, the same calculation is used as for all Operations in the group, and the lowest Operation availability is returned.

OEE Performance

Performance is calculated as Ideal Cycle Time / (Operating Time / Total Pieces).

The Ideal Cycle Time for each process point is recorded in the iMonitor settings area of the Analytics client application and does not change unless modified by an operator.

Total Pieces is calculated by counting up the number of WIP transactions recorded during the planned production time, where planned production time is calculated as described above. If availability is an issue, it may be easier to get a high-performance figure because total pieces is determined across the whole planned production window, and not just the operating window. This is an integral part of OEE design which is designed to focus on availability in that situation.

OEE Quality

Looks at first pass yield achieved during planned production time during a specified time window.

Quality = (Total Pieces – Total Failed) / Total Pieces