Existing equipment. New possibilities.

Equipment modernization

Keep what works.
Renew what matters.

I assess the existing control system and develop a modernization plan for PLCs, HMI, drives, industrial communication and electrical equipment. Serviceable components stay where retaining them makes technical sense.

Discuss modernization View projects

One machine. Two control systems.

Schematic example

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More new50 / 50More existing

A technical illustration, not a customer before-and-after. The replacement scope and target platform follow from assessment.

What actually needs replacing?

Select a component. Each part needs its own decision about retention or replacement.

The machine foundation

Mechanics

May be retained if condition, remaining usability and process function meet the task. Assessed alongside the mechanical scope of the project.

Load and control

Motor

Condition, rating, operating modes, insulation, cooling and compatibility with the proposed drive are checked. A new drive does not automatically require a new motor.

Process signals

Sensors

Ranges, accuracy, supply, signal types and condition are checked. Serviceable, compatible sensors can often be incorporated into the new system.

Electrical equipment

Cabinet

Wiring, protection, available space, cooling and documentation are assessed. Reuse of the existing cabinet depends on the survey.

Logic and I/O

PLC

Unavailable components or an unsupported engineering environment can warrant migration assessment: software, I/O, cycle times, interfaces and hardware constraints.

Operator interaction

HMI

Unavailable spare panels, source projects or required features may call for replacement. Tags, recipes, archives and operator actions are reviewed.

Motion and torque

Drive

Where suitable repair or replacement is unavailable, the motor, load, power, control and communication are assessed. Selection is not based on kW alone.

Data exchange

Network

Protocols, topology, nodes and diagnostics are checked. Suitable supported connections may stay; migration or gateways depend on compatibility.

Every decision depends on condition, requirements and the particular project.

Modernization does not start from zero.

First, understand the value already built into the machine. Then renew the parts that limit its operation.

Reuse serviceable mechanics
Avoid unnecessary replacement
Reduce reliance on scarce spare parts
Improve diagnostics
Prepare for future changes
Enable continued use

Potential benefits depend on the project. No specific saving or additional service life is guaranteed.

Several routes. The right destination.

Possible modernization paths. Machine function, I/O, communication, requirements and maintainability determine the target platform.

SIMATIC S5 / STEP 5Modern PLC

S7-300 / S7-400Suitable current platform

Legacy HMIPanel / IPC / SCADA

Legacy driveDrive suited to the task

Legacy communicationSupported interface

STEP 7 Classic, TIA Portal, S7-1200 and S7-1500 reflect practical experience, not a universal replacement chart. Other platforms can be considered for the project.

Explore a modernization example.

The starting conditions are fixed for this demo. It illustrates the assessment process without selecting equipment.

Starting system01

PLC: SIMATIC S5
HMI: Legacy operator panel
Drive: Legacy drive
Network: PROFIBUS

Example ready for assessment

Schematic example

01
PLC
Assess software, I/O, cycle time and interfaces.
02
HMI
Check the project, tags, recipes and functions.
03
Drive
Review motor, rating, control and communication.
04
Network
Determine what can stay and what needs changing.

The result: a modernization plan.

Define the work, checks and a suitable transition. PROFIBUS in this example does not mean the network must automatically be replaced.

Schematic demo only. No equipment connection, automated engineering verdict or specific purchasing recommendation.

Five phases. One coordinated transition.

Project modules move from an uncertain baseline to a tested control system.

Assessment

Software, hardware, I/O, networks, documentation and actual machine operation.

Concept

What stays, what changes and which interfaces must be preserved?

Preparation

PLC/HMI software, hardware selection, drawing changes and planned checks.

Switchover

An agreed modification sequence and migration on the real machine.

Commissioning

Operating modes, automatic sequences, optimization and handover.

Preserve the function. Question the old faults.

Legacy code contains knowledge about the machine. But a blind one-to-one copy does not always produce a good new system. The process function and its requirements come first.

Process function and operating modes
Sequences and operational interlocks
Required external interfaces
Known faults and unclear code
Program structure and diagnostics

Legacy code

Machine function

Clear structure

Safety functions are assessed separately against the safety concept and required verification. Ordinary PLC software migration does not replace safety engineering.

Make the drawing match the machine again.

After several modifications, documentation and reality may diverge. Modernization can include reviewing and updating the records within the agreed scope.

Existing system

Drawing V1
Modification
Another change
Machine ≠ documentation

Migration

Survey
Verified circuitry
Current software
Agreed project record

A complete new set of EPLAN drawings is not automatically included in every modernization. Documents, backups and handover scope are agreed for the project.

Real projects / 001

Harbor crane in Batumi in an original photograph from the modernization project — Original photograph from Case 001. Not a before-and-after pair.

Case 001 · Batumi · 2024 · 12 t

Keep the crane. Replace the critical technology.

The harbor crane used Mannesmann drives without available spare parts or manufacturer support. A transition to Emotron was developed for the existing crane.

MannesmannEmotron

Hardware selected with the manufacturer
Electrical drawings and STEP 7 software adapted
Five new drives integrated and configured
Crane commissioned on site

The crane was modernized and commissioned. The published case also documents an engineering PG prepared for remote service.

Read the case

Real projects / 006

Existing Weidmüller communication node from Project 006 — Original equipment from Case 006. The photo does not show the new ОВЕН ПЛК210.

Case 006 · 2026 · Delivered remotely

One component. A system reconnected.

A failed Weidmüller communication controller interrupted exchange between TPEM and Siemens S7-1500. Direct replacement was unavailable. A new solution was developed using ОВЕН ПЛК210 and CODESYS V3.5.

WeidmüllerОВЕН ПЛК210

Modbus RTU on the TPEM side
Modbus TCP on the Siemens side
Existing Siemens data structure retained
Operation restored without a full control system rebuild

The entire machine need not be standardized on one brand. Compatibility and a technically sound solution matter more.

Read the case

Running today. Recoverable tomorrow?

Operability and repairability are different questions. Planned modernization is easier to prepare than a transition after a complete failure.

Spare parts become harder to source
Engineering runs only on an old PC
Software is poorly documented
A panel or communication module is difficult to replace
Recovery time is difficult to predict

Demonstration example

Change the example conditions

PLCHMIDriveDocumentationBackup

Review priority in this exampleMedium

Check PLC and engineering availability
Review the HMI and project migration options
Prepare a technical assessment of drive replacement
Check documentation against the actual machine
Verify backup completeness and restorability

Keep the verified baseline and periodically check component availability. No issues are flagged in this example.

Simplified indicator: 0–1 flagged issues = low, 2–3 = medium, 4–5 = high. This is not a risk calculation for your machine.

Age is a reason to assess. Not to discard.

Working equipment does not become bad simply because it is old. Yet support, spare parts, expansion options and engineering tools may limit its continued use. Each component deserves its own assessment.

Plan around production.

The transition needs an available shutdown window and a clear sequence. Some work can be prepared in advance; a phased approach depends on the project.

Before the shutdown

Prepare the software
Prepare hardware and drawings
Back up the original system
Agree any feasible fallback

During the transition

Agree the shutdown window
Follow a clear modification sequence
Check the completed installation
Commission and hand over

Rollback is not possible in every architecture. Modernization without production downtime is not promised.

Understand the old to build the new.

STEP 5, STEP 7 Classic, older Siemens systems, HMI projects and drive engineering tools help reveal the original function. That understanding informs the new architecture.

Experience and qualifications ↗

STEP 501

STEP 7 Classic02

TIA Portal03

Have an old part number?

Send the type, a nameplate photo and a description of its function. This provides a starting point for assessing modernization options.

For example: 6ES5… / 6ES7… / HMI or drive type

Review modernization options

Personal review through the contact page. No automatic spare-part matching is provided here.

Before the project starts

Does the complete machine need replacing?

Not necessarily. The condition, function and compatibility of each part are assessed. What can stay and what must change follows from that assessment.

Which PLC platform is used for migration?

There is no universal replacement. I/O, software, cycle time, networks, maintenance and project requirements guide the choice. Siemens S7-1200/S7-1500 and other platforms are considered for the task.

Can existing motors and PROFIBUS remain?

Possibly, if condition and compatibility permit. Motors, network and nodes are assessed separately. A name or age alone is not enough to promise retention.

Can the change happen without downtime?

That depends on architecture and scope. Advance work and phased implementation may help, but installation, checks and commissioning generally require an agreed window.

What happens to software and documentation?

The original project is reviewed. Software, drawings, backups and documentation are handled within the agreed scope. Safety functions are considered separately.