Modernization Strategy
PLC Migration Consulting
From an obsolete controller to a system your team can support, with the downtime planned instead of forced on you.
A PLC migration gets presented as a hardware replacement and delivered as a software rewrite. That gap is where the schedule and the budget go. Joltek provides independent PLC migration consulting for plants moving off SLC 500, PLC-5, S7-300 and other obsolete controllers: we pick the path with you, put a real dollar range on it, plan the cutover around your shutdown windows and hold the integrator to a standard your team can support afterwards.
Proof. Before founding Joltek, Vladimir Romanov led the migration of more than 120 servo axes from the discontinued Rockwell 1394 platform to Kinetix 6200 on an FDA-regulated packaging line, inside a planned two-week shutdown (case study). At Joltek, we stabilized a packaging line where three OEM machines on Omron control fed a Rockwell cartoner with no source projects and no direct network path between them (case study).
For the technical background, see our guides to SLC 500 migration, PLC platform migration planning, what a PLC-5 and SLC 500 migration actually involves and the Allen-Bradley lifecycle.
Why it matters
What this costs when it is left alone
The reasons this work gets deferred are usually the reasons it gets expensive.
The spare is the last spare
When the replacement processor comes from an aftermarket broker at several times its original price with no warranty, the migration has already started. It is just happening on the failure's schedule instead of yours.
Conversion is not translation
Migration tools move instructions, not meaning. Fixed data files such as N7:12 have to become named tags, and the information to do that well lives in documentation and in people, not in the program.
An emergency cutover costs more than a planned one
Lost production during a forced replacement usually exceeds the premium of migrating on a planned schedule. That comparison is the business case a capital committee will fund.
Unpatchable hardware on the plant network
Legacy controllers receive no security updates. Every year they stay connected, the exposure grows and the audit finding gets harder to explain.
Our approach
How the work runs
Every migration resolves to one decision first: like-for-like or re-architecture. We make that decision with you line by line, then plan the work around your downtime windows.
Assess and choose the path
- I/O audit, program review and documentation gap list
- Like-for-like, staged or full re-architecture, decided per line
- Target platform chosen for your site, not for a vendor
Plan the cutover
- Functional description of what the new system must do
- Cutover plan sized to the shutdown window, with a tested rollback
- Spares strategy for the old platform until the last line moves
Govern the delivery
- Scope, acceptance criteria and FAT/SAT plan for the integrator
- Code and design reviews against your standards
- We deliver the controls work ourselves where that serves the plant better
Hand over and sustain
- Validation and commissioning witnessed against the acceptance criteria
- Documentation and training your team can maintain
- A fleet sequence for the lines and sites still to come
What it costs
Planning ranges, in full dollars
A migration has no single price. These ranges are order-of-magnitude anchors for a budget conversation, built from the projects we have planned and reviewed.
| Scope | Typical path | Planning range |
|---|---|---|
| Single processor, small I/O count | SLC 5/05 swap, or 1747-AENTR conversion to a Logix controller with field wiring kept | $10,000 to $75,000 |
| Single PLC, program rewritten | SLC 500 or PLC-5 to CompactLogix or ControlLogix, I/O conversion kits, HMI updated | $50,000 to $200,000 |
| One production line, like-for-like | Controller, I/O and HMI migrated, control philosophy kept, full validation | $150,000 to $400,000 |
| One production line, re-architected | New code structure, network and HMI, often historian and data feeds | $300,000 to $750,000 |
| Plant or multi-line program, including SCADA | Sequenced across shutdowns and fiscal years, standard design reused site to site | $1,000,000 and up |
Ranges cover hardware, engineering, conversion, HMI changes, validation and commissioning. They do not include the cost of downtime itself, which is why a planned migration usually beats an emergency one. Treat them as planning anchors, not a quote: I/O count, code quality, documentation, network type (DH+, Remote I/O, DeviceNet) and the length of your shutdown window move the number most.
What we deliver
What you end up holding
- I/O audit and program review with a documentation gap list
- Migration path recommendation per line, with cost and risk
- Functional description for the new control system
- Cutover and rollback plan sized to the shutdown window
- Integrator scope, acceptance criteria and FAT/SAT plan
- Commissioning record, as-built documentation and handover
Who we support
Who this is for
- Engineering and automation managers
- who own an aging controls estate and need a migration plan they can defend to finance and to operations.
- Plant and operations leaders
- who cannot afford a line down for weeks and need the cutover sized to the shutdown they actually have.
- Corporate engineering teams
- standardizing the target platform and code across several sites, and sequencing the capital over years.
Why Joltek
What you are actually buying
On your side of the table
No vendor or integrator pays us, so the path we recommend is the one that fits the plant, including keeping what you have when that is right.
We have done the cutovers
The plans are written by people who have commissioned migrations inside fixed shutdown windows, not drawn up from a catalog.
Planned, priced and governed
A path, a range in real dollars, acceptance criteria and someone accountable for the result, from assessment to handover.
Questions
Answered before you ask
Can the Rockwell conversion tool migrate our PLC-5 or SLC 500 program for us?
It converts the instructions, not the intent. Fixed data files become generic tags, indirect addressing and timing behaviour need manual review, and the result still has to be tested on the new hardware. Plan on the tool doing a first draft and engineers doing the rest.
How long will the line be down?
It depends on the path. A processor swap or 1747-AENTR conversion that keeps the field wiring can fit a weekend. A line migration with new I/O and HMI usually needs a planned shutdown of days to a couple of weeks. We size the cutover plan to the window you have, with a tested rollback.
Do we have to replace the I/O and the field wiring?
Not always. Conversion kits and adapters let many migrations keep the existing field wiring and even the I/O racks for a first phase. Whether that is the right call depends on spares availability and the long term plan for the line.
Can you work with our existing integrator?
Yes, and that is the most common setup. We act on your side as the technical lead: scope, acceptance criteria, design and code reviews, and FAT and SAT witness. Where it serves the plant better, we deliver the controls work ourselves.
What does a PLC migration cost?
As planning anchors, a single PLC migration with a rewritten program commonly lands between $50,000 and $200,000, and a single production line migrated like-for-like between $150,000 and $400,000. The ranges table above shows the full spread. A real number comes from the I/O audit and program review.
We run Siemens S7-300. Is this only for Rockwell plants?
No. The same decisions apply to S7-300 to S7-1500, S5 to S7 and other platform moves. We are vendor-neutral, so the target platform is chosen for your site.
Have a project that needs technical ownership?
Send us the situation. If it is not something we should take on, we will say so.