OT to IT integration
PLC and SCADA integration with MES and ERP
PLC and SCADA integration connects the control layer of a plant to business systems, so machine counts, states and process values reach the MES and ERP automatically, and orders and recipes flow back down. Done well, it is read only where it should be, buffered against outages, and never puts the machine program at risk.
Free scoping call. We start with one line, never change your machine logic, and you own the code and the data.
- material movements tracked a day, integrated steel plant
- 720,000+
- fewer dispatch errors with RFID and barcode dispatch
- 90%
- items an hour through RFID warehouse automation
- 16,800
Company reported project figures, not independently audited, not a promise for another plant. Samsung Business Insights: our RFID warehouse automation story (opens in a new tab). Forbes India Brand Connect (sponsored): founder profile (opens in a new tab).
Sound familiar?
- Operators retype counts from HMI screens into the ERP.
- A vendor wants direct access to your PLCs and your controls team says no.
- The SCADA holds years of useful data on an unsupported operating system.
- Every integration is a one off script that only one person understands.
Each of these is output, margin or time you have already paid for and are not getting back.
What you get
An integration map
Which systems, which data, which direction and how often, agreed with controls and IT.
A tag and interface list
Every tag read or written and every ERP transaction, documented.
Safe first, then useful
Read only pilot on one line; writes only after tests and sign off.
Handover
Monitoring, documentation and support procedures for your team.
What we have built
Our RFID and QR based vendor material system syncs with SAP in real time, covering vendor materials worth more than ₹20,000 crore (about US$2.4 billion) moved every day.
Figures are company reported from past projects. They are not independently audited benchmarks and are not a promise for another plant. Read the case studies.
How we work
What we deliver
We deliver the integration layer: tag lists and naming, edge gateways, OPC UA and MQTT backbone, MES or middleware logic, and ERP interfaces, with OT network segmentation guided by ISA/IEC 62443. We work alongside your controls team or system integrator, who remain responsible for the PLC programs.
How a project starts
- 1Integration map. Which systems, which data, which direction, how often.
- 2Tag and interface list. Every tag and ERP transaction agreed with controls and IT.
- 3Pilot on one line. Read only first; downward writes only after testing and sign off.
- 4Roll out and hand over. Documentation, monitoring and support procedures for your team.
How it works
Integration patterns we use
- PLC data integration: read tags over OPC UA, Modbus TCP or the controller protocol, through an edge gateway.
- SCADA integration: take data from the SCADA server or historian over OPC UA or its API instead of polling every PLC twice.
- PLC to ERP and PLC to SAP: controller events go to the MES or integration layer, which posts confirmations and goods movements to the ERP.
- Downward flows: recipes, setpoints or order data written to the PLC through defined handshake tags, with interlocks and change control.
- Event streaming: MQTT from edge to broker so many applications can subscribe without extra load on the controllers.
Protocols compared
| Protocol | Best for | Watch out for |
|---|---|---|
| OPC UA | Modern PLCs, SCADA, structured data with types and security | Server licences or options on some controllers; session limits |
| Modbus RTU and TCP | Drives, meters, older controllers, simple devices | Register maps must be documented; no built in security or data types |
| MQTT | Publishing edge data to many consumers across sites | Needs a naming convention and payload standard, for example Sparkplug B |
| Vendor protocols | Controllers without OPC UA | Driver availability and version support |
SCADA modernization and legacy PLC integration
Old SCADA systems often hold years of useful data but run on unsupported operating systems. Modernization can mean replacing the SCADA, or keeping it and adding a modern integration and reporting layer beside it. Legacy PLCs without Ethernet can be reached through serial gateways or protocol converters. The priority is always the same: keep the process running, test on a copy or during a planned stop, and document every tag that is read or written.
Background
What OT to IT integration means in practice
Operational technology is the control layer: PLCs, drives, SCADA and HMIs that run the machines. Information technology is the business layer: MES, ERP, quality and maintenance systems. Integration moves the right data between them at the right speed. Controllers work in milliseconds; ERP works in transactions. The MES or integration layer in the middle translates signals into business events such as "order 4711 produced 480 good pieces".
| Level | Systems | Passes on |
|---|---|---|
| Level 4 | ERP such as SAP S/4HANA, Oracle, Dynamics | Orders, materials, confirmations, costs |
| Level 3 | MES, quality, maintenance, warehouse | Work orders, genealogy, OEE, quality results |
| Level 2 | SCADA, HMI, historian | Supervisory control, trends, alarms |
| Level 1 and 0 | PLCs, drives, sensors, actuators | Signals, counts, states, process values |
When we are not the right choice
- You need PLC programming or panel building. Your controls integrator should do that; we work alongside them.
- A single CSV export once a day already meets the need.
Common concerns, answered
Will this disrupt production?
No. We connect read only first, install during planned stops, and edge devices buffer data so a network problem never stops a machine. Nothing writes to a PLC without your controls team and a test.
Our machines are old. Do we need to replace them?
No. Old machines are the usual case. A running signal, a cycle signal or a current sensor on the motor is enough to start, without touching the machine program.
We tried a system before and nobody used it.
That is the most common failure, so we design with the operators and supervisors who will use it, start with one report they already fill in by hand, and only extend once they rely on it.
What about IT security?
Read only by default, a segmented OT network, and a review with your IT team before anything connects, following the ISA/IEC 62443 zone approach.
We will not replace SAP or Oracle. Do we have to?
No. We connect to the ERP you already run through its standard interfaces and add what the shop floor is missing. Your ERP stays the system of record.
Do your engineers understand a heavy industrial floor?
Our systems run in steel plants, warehouses and process lines. We start every project by walking the line with your operators and supervisors, and the first release is tested by them, not only by IT.
Are we locked in?
No. You own the source code and the data, documented, in your own repository. Another team can maintain it.
Frequently asked questions
Can a PLC connect directly to SAP?
It is technically possible but rarely a good idea. SAP expects business transactions, not signals. An MES or integration layer turns PLC events into confirmations and goods movements, handles errors and retries, and keeps SAP free of machine level traffic.
Will integration change our PLC programs?
Reading data does not require program changes if the tags are accessible. Writing data to a PLC usually needs a small handshake block agreed with your controls engineer. We do not change control logic without your controls team.
Which is better, OPC UA or MQTT?
They solve different problems. OPC UA is strong for structured, secure connections to controllers and SCADA. MQTT is strong for publishing data from the edge to many consumers. Many architectures use OPC UA at the machine and MQTT above it.
Do you work with Siemens, Rockwell, Mitsubishi and other PLCs?
Yes. We connect to common controller families through OPC UA, their native protocols or gateways. The method depends on the model, firmware and available options, which we confirm in the survey.
How do you keep integration secure?
Segment the OT network, allow only defined connections through a controlled boundary, use read only access where possible, authenticate OPC UA sessions and keep an asset and connection register. ISA/IEC 62443 is our reference.
Related reading
References
Start with one line and one number
We scope one line, agree the number that should move, and show it moving before anything is scaled. You keep the code and the data.
Step 1
An engineer reads it
Not a sales bot. Our team replies within 24 hours with questions or times for a call.
Step 2
30 minute call
Your process, machines, systems and the number you want to move. We tell you honestly if we are a fit.
Step 3
A written scope for one line
What we would connect, what you would see, how long it takes. You decide; nothing starts without your approval.
Reviewed by Amey Kadle, Founder, Ajinkya Technologies. Last reviewed: .