The Path from Data to Actionable Information as a Driver for the Industrial Ecosystem
Production time can be further broken down into the following categories in Figure 6 21 :
Figure 6: Production Time
schedule to determine if the machine is
operating when it was scheduled to be
operating; allowing one to discern Plant
Operating Time, Scheduled Operating Time
from Potential Production Time and
compute Delay Time as well as Lost
Production time, which is the Production
Time minus the Potential Production Time.
To categorize time, one needs to understand
the equipment’s current operation states
and when essential work is being done
necessary to producing parts, even if it is
ancillary to the production process. One
should start by getting as much data from
the controller as possible, use proprietary
APIs or binary signals from PLC terminal
blocks. The data must be translated into a
timestamped stream of tagged values.
Q UALITY
The quality metric [3] is often ignored in
discrete
manufacturing
since
most
manufacturing processes have multiple
steps and inspection is often performed at
the end. There are problems attributing the
quality slip to the device and process step
since there are many operations that create
a single feature; it is often impossible. In
most OEE systems, quality is reported at
100%, unless a capability exists at the
machine to report scrapped parts or the
operator identifies bad parts and enters the
data manually.
The next phase translates the data from the
tag value pairs to the MTConnect standard
by taking the tagged data and converting
units and determining standardized machine
states. After the semantic conversion, rules
can be applied to multiple machine vendors
and models. Sensor data can be analyzed to
identify anomalous conditions and translate
the conditions into MTConnect semantics
using machine learning.
The initial categorization is done during the
enrichment stage where the semantic data
are matched with patterns that indicate
production, repair, setup and non-
productive. At the next stage, ecosystem
integration with MES gives the plant
Processes must be verified at each step for
OEE to work properly. When we increase the
part mix and variation, it is even more
imperative that every step is verified. The
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June 2018