The following descriptions and tables describe a ControlLogix user-defined data type (UDT) that can be
created as an array in ControlLogix. The UDT is then populated for each work cell with the corresponding
data for that work cell. This practice makes replication and troubleshooting much easier for the end-user.
Through this OEM
TM
Accelerator – OEE exercise, OEMs and system integrators preconfigure equipment for
direct connection to PlantMetrics or LPS (Line Performance Solution).
When configuring a work cell, there are two types of information that can be used. The first is the
performance parameters of a work cell and include ideal cycle time, part counters, availability and running
status, and summarization criteria like part ID, operator ID, SKU, work order, etc.
Ideal cycle time in seconds per part can be a fixed number but typically comes from the control system as it
may change by part ID. Two of the three part counters must be provided and should be provided in the
same units. PlantMetrics has the ability to recognize when part counters are reset in the control system.
The summarization items like part ID, operator ID, SKU or lot number, and work order can be configured as
desired and are used on an event by event basis to determine how those events are summarized. In
general, PlantMetrics inserts a record into the appropriate table, and then updates the values in that record
every 10 seconds until the record is complete (in the case of an event record, when the event ends) or the
summarization rules dictate that the current record should be closed and a new record created.
The second type of information configured in PlantMetrics is the custom user events. A recommendation is
to create a work cell state event that contains a unique machine state and changes values based on the
state of the machine. The following table has some examples of states and corresponding values that are
populated in the UDT.
Value
State
1
Blocked
2
Starved
3
Power
4
Changeover
5
Machine Setup
6
Bypassed
7
Manual
8
Idle
9
Ready
10
Faulted
Other custom user events could include machine faults and operator stop reasons. Typically, a work cell
cannot produce when a machine is faulted and there are typically multiple fault conditions possible (Fault
reason codes). The root cause fault should be captured and trapped. These fault events should have a
discrete trigger that designates when the event starts and a corresponding word value (Fault reason code)
that designates what the corresponding fault represents. A lookup table similar to this should be included
and populated in the UDT
