Allen-Bradley, Mitsubishi & Delta to Siemens Migration

Why Plants Standardise on One Platform

Most plants do not choose a mixed estate; they inherit it. A line bought from one builder arrives on Allen-Bradley, the packing machine comes on Mitsubishi, a retrofit adds Delta, and after fifteen years the maintenance team carries four programming environments, four spares lists and four sets of skills. Standardising cuts the spares holding, shortens fault-finding, and means one engineer can work on any line in the plant.

Siemens is the usual destination in India because the skill base, the spares availability and the service network are the deepest. That is a commercial argument, not a technical one, and it only holds where the plant has enough lines to make standardisation worth the disruption. On a single isolated machine it usually does not.

What Cross-Platform Migration Actually Involves

There is no tool that converts Allen-Bradley or Mitsubishi logic into Siemens code you would want to run. The data types, the addressing model, the task structure, the instruction behaviour and the way each platform handles timers, edges and retentive memory are different, and a literal translation reproduces the quirks of the source platform inside the target one.

The work is: read and document the existing logic, extract the control philosophy from it, then write that philosophy properly in TIA Portal. Sequence-by-sequence, against the machine, with the plant’s own operators confirming what each step is supposed to do. That is slower than a conversion and it is the only version that is maintainable afterwards.

The Parts People Underestimate

Analogue scaling and engineering units that differ between platforms. Timer and counter behaviour at the edges. Retentive memory and first-scan handling after a power failure. Drive interfacing, where the fieldbus, the parameter set and the fault words all change. Third-party devices — weighers, barcode readers, temperature controllers, safety relays — each speaking a protocol that now has to be re-established. Safety circuits, which are re-engineered and re-validated rather than copied. And the HMI or SCADA, which is a project in its own right.

How We Stage It

Survey and documentation of the installed system, including an I/O list taken from the panel. Control philosophy written down and agreed with your production and maintenance teams. Hardware selection and panel retrofit design. Logic written and simulated offline, with factory acceptance testing before travel. Changeover during a planned window: swap, loop checks, dry runs, start-up with our engineers on site. Then stabilisation, documentation and operator training.

On multi-line plants we migrate one line first and run it for a full production cycle before touching the next. It costs a little more in mobilisation and it removes most of the risk.

What You Get at Handover

Programme sources in TIA Portal, current GA and wiring drawings, I/O and instrument schedules, backups, the SCADA or HMI project, and operator and maintenance training. The plant owns its control system afterwards — no locked blocks, no dependency on us to make a routine change.

After the Migration

Annual maintenance, programme backup and version control, Siemens spares supply, and remote PLC and SCADA troubleshooting so that most faults are diagnosed before an engineer travels. ATMAN Group is a project, service and spare-parts provider; we are not an authorised Siemens channel.

Discuss a Migration

Tell us which platform you are on, roughly how many I/O and how many lines, and what window you can offer, and we will come back with a method and an indicative budget.

Frequently Asked Questions