First thing's first, there's often quite a bit of confusion in terms of the roles and responsibilities between an ERP, an MES, and a SCADA. This is thanks to the overlap of responsibilities between these 3 systems that has developed over the decades and because they're all connected at the hip and share tremendous amounts of data (or they should if not already!). Although there is debate regarding the validity of ISA-95's classifications in light of Industry 4.0 advancements, the framework still provides a strong guidance towards how the shop floor should view these 3 solutions of the ERP, the MES and SCADA.
What's important to note is that even though the lines between each of the ISA-95 pyramid segments are blurring, the hierarchy still help organizations big and small wrap their heads around identifying packaged solutions. For example, if you're out in the market looking for an ERP system, you'd generally want to ensure that features like long term planning, quotations, purchase orders, costings, etc. are strong and available in the package. These features fit within the daily/monthly time-frame as required for the enterprise "planning" as a whole. However when we setup in the realm of the MES, hourly and even minute time-frame events become important, which involves production scheduling, quality control, maintenance operations, etc. This nitty-gritty of the shop floor operations is the responsibility of the MES. Finally when we get to the SCADA, this is designed for minute/second level operations for the physical equipment and machines such as controlling automated valves to open/close or executing certain programs/recipes on a automated line, etc.
Since each one of these systems all run on different time-frames, trying to have one solution/vendor/architecture do everything can end up being catastrophic.
Jack of all Trades, Masters of None
Based on the above, ERP/MES/SCADA all run on different time-frames. Trying to lump them all together or source from a single vendor/supplier to setup in the same architecture can end up in disaster or burn through your budget faster than you can blink. Although not impossible, it's equivalent to forcing a square peg into a round hole.
Let's take an example - one of the biggest hassles of production scheduling on the shop floor is unforeseen adjustments/changes in actual vs. planned scheduling. If you were to use an ERP system to try to manage all updates of actual production timings, this would mean each hour/minute there is a delay or change to actual production schedules based on live user feedback on tablets/machines/sensors, etc. it would need to send information back up through to the ERP system. This can work if you're just running a small 2-3 line/machine/station workshop that has 10-20 transactions per line per hour, but if you were to have 30-40 lines/machines/stations, that would imply, 300-800 transactions/hour which is a transaction of about every 4.5 seconds!
When these transactions occur, the full daily plan needs to be re-optimized, updated, pushed back to the shop floor and incorporate feedback and updates if necessary. ERP systems were never designed to deal with such a rapid rate of processing/coordination on top of their existing responsibilities of long term planning/forecasting and helping the sales team deal with quotations and purchase orders!
Focus on Pain-point Solving, Not on Bundled Solutions
Therefore when it comes to sourcing specific toolsets for the shop floor, it's much more critical to focus on functionality than it is on the bundle/single vendor. This will help reduce the jack of all trades syndrome and ensure the functionality fits the pain point that you're trying to solve.
Recently I had the honor to speak with Rick Franzosa from Gartner on this topic and we discussed how the concept of the MES is no longer about the confines of the definition, but instead about the functionality and the features it needs to/can cover. The understanding of the shop floor pain points comes first, then finding the strategic solution that has the best capabilities to solve the problem can come from anywhere. New Industry 4.0 solutions have blurred the lines between systems (IoT Platforms, Integrated Platforms, etc.) and it doesn't mean that you need to purchase a full encompassing system for the entire enterprise, but instead, finding the best in class solution to tackle shop floor pain-points will not only be more cost effective but also a much better fit for your operations.
The Future Solutions & The Importance of Integration
With new and better solutions for targeted pain-points coming out constantly that cross the boundaries of the ERP/MES/SCADA divide, integration becomes key. Even if you already have an existing vendor with solution deployed, it doesn't mean you need to be tied to the same as you scale and grow. Smooth data transitions between the ISA-95 levels becomes critical to ensure full transparency and control.
As we march forward towards realizing Industry 4.0, manufacturers will realize that in order to take advantage of best in class solutions, it will mean taking on different solutions through-out the enterprise. Two identical facilities may require different solutions and within an enterprise, different shop floors may require different MES/SCADA/PLC solutions (i.e., a chemical batched based factory may need a different MES than a discrete high mix, low volume factories even if both factories are in the same enterprise). Even if you already have an existing vendor and solution deployed, doesn't mean you need to be tied to the same as you scale and grow.
This mindset change for management, shop floor managers and IT/OT managers is fundamental to ensure enterprises take full advantage of new transformative Industry 4.0 solutions. Gone are the days of one size fits all and the hope that one vendor can cover all your needs. Best in class diversification of solutions to solve targeted pain-points and IT/OT teams focused on solutions integration will become the new norm for manufacturers. Though this will not be an easy change nor adjustment, it is the best preparation to ensure your organization is nimble, agile and capable of incorporating solution-based advantages in the market as quickly as possible to turn it into a competitive advantage.