System Retrofitting & Upgradation

Product Overview

Modernise Without Starting Over

Legacy PLC and DCS systems — many over 20 years old — represent a growing risk: spare parts become unavailable, software stops being supported, and the skills gap widens. Yet replacing a running plant control system is not trivial.

Hi-Tech Automation specialises in risk-managed retrofits: we assess your existing system, design the migration architecture, and execute the cutover in planned maintenance windows — often without a single unplanned shutdown.

Like-for-like I/O mapping with signal verification
Logic conversion and program re-engineering
Phased cutover with parallel run options
Operator retraining on new HMI/SCADA
Full as-built documentation handover

Migration Paths

Legacy Systems We Migrate From & To

Legacy Systems (From)

Siemens S5 / S7-300 Allen Bradley PLC-5 / SLC-500 Modicon 984 / Quantum GE Series 90 / Fanuc Yokogawa CENTUM CS / μXL Honeywell TDC 2000/3000 ABB Master / Procontrol Relay/Hardwired Logic Panels Analogue Instrumentation

Modern Platforms (To)

Siemens S7-1200 / S7-1500 Allen Bradley ControlLogix / 5000 Schneider M340 / M580 ABB AC500 / System 800xA Yokogawa CENTUM VP Honeywell Experion PKS Emerson DeltaV WinCC / iFIX / Wonderware SCADA Modern MCC / VFD Panels

Our Process

Structured Retrofitting Methodology

01

System Audit & Assessment

Complete inventory of existing hardware, software revision, I/O count, network topology, and failure risk classification.

02

Retrofit Design & Proposal

Migration architecture, platform selection, I/O mapping, and cutover plan with risk assessment and ROI calculation.

03

Logic & Program Re-Engineering

Manual or tool-assisted conversion of ladder logic, function blocks, and HMI graphics to the new platform.

04

Panel Fabrication & Factory Testing

New control panels built in-house and fully tested with the re-engineered programs before site delivery.

05

Phased Site Cutover

Planned shutdown windows for parallel wiring, loop checking, and cutover — minimising process interruption.

06

Commissioning & Handover

Functional testing, operator training, as-built drawings, and 12-month warranty support post-commissioning.

Benefits

Why Retrofit Instead of Replace Everything?

Lower Capital Cost

Reuse field instruments, junction boxes, cable trays, and civil infrastructure — investing only in the control hardware that needs replacing.

Minimal Downtime

Phased cutover strategies allow most wiring work to happen while the plant runs — planned shutdown restricted to final cutover and loop testing.

Improved Reliability

Move away from obsolete hardware with no spare parts to modern, redundant platforms with global support and a 10+ year product lifecycle.

Enhanced Diagnostics

New SCADA with trend history, advanced alarming, OPC-UA connectivity, and remote access capability not possible on legacy systems.

Preserved Process Knowledge

Careful logic re-engineering captures years of operational tuning — no institutional knowledge is lost during migration.

Industry 4.0 Ready

Modern platforms enable OPC-UA, MQTT, cloud connectivity, and MES integration — unlocking data-driven operations.

Improved Safety

Replace relay-based safety interlocks with SIL-rated Safety PLCs — bringing legacy plants up to current IEC 61511 standards.

Full Documentation

Receive complete as-built P&IDs, wiring diagrams, I/O lists, and program backups — often the first time the plant has accurate documentation.

Applications

Industries We Retrofit

Power Generation

Boiler control, turbine governor, unit auxiliary DCS migrations from TDC/CENTUM CS to modern Experion PKS or CENTUM VP.

Sugar & Distillery

Mill tandem PLC upgrades, boiler relay panel modernisation, and distillery process automation retrofits.

Chemical & Pharma

Batch reactor PLC migrations, legacy DCS-to-DeltaV upgrades, and GMP-compliant SCADA replacements with 21 CFR Part 11.

Paper & Pulp

Drive system retrofits, paper machine DCS migration, and replacement of hardwired relay interlocks with modern PLCs.

Oil & Gas

ESD panel upgrades to modern safety PLCs, pipeline SCADA migrations, and wellhead RTU modernisation projects.

Water & Utilities

WTP/STP SCADA upgrades, PLC replacements for pumping stations, and remote telemetry modernisation for municipalities.

System Retrofitting & Upgradation

Modernise Without Starting Over