Modular PLC System — Datasheet

Overview

Overview

Modular PLC System is a DIN-rail Programmable Logic Controller built for industrial machine logic: a deterministic CPU plus a snap-together stack of digital, analog, high-speed counter and comms modules. Engineers program in IEC 61131-3 ladder, structured text, function block or SFC; field devices wire straight into spring-cage terminals.

Designed for OEM machine builders, system integrators and plant maintenance teams who need real-time control with deterministic scan cycles, diagnostics, and a path from prototype to production on the same hardware family.

• Modular by design — mix DI, DO, AI, AO, HSC, fieldbus modules to match your I/O count
• Deterministic scan — 1–10 ms cycle, <0.1 ms jitter
• IEC 61131-3 — ladder, structured text, function block, SFC, instruction list
• Fieldbus options — Modbus RTU/TCP, Profinet, EtherCAT, EtherNet/IP, OPC UA server

How It Works

1. CPU module on the leftmost DIN-rail slot reads the I/O backplane bus every scan, runs the user program, and writes outputs at deterministic intervals.
2. I/O modules snap onto the rail to the right of the CPU; the backplane connector auto-addresses them. Hot-swap supported for field replacement.
3. Field devices (sensors, valves, motors, drives, encoders, E-stops) wire into spring-cage terminals on the front of each I/O module.
4. Scan cycle — read inputs → execute logic → write outputs → housekeeping & comms → repeat.
5. Engineering IDE on a laptop talks to the CPU over Ethernet; engineers download programs, monitor live tags, set breakpoints, force values for commissioning.

Features

• 5 IEC 61131-3 languages — LD, ST, FBD, SFC, IL in one project
• Hot-swap I/O modules — replace a faulty card without powering down
• Online edit — modify running logic without stopping the machine
• Diagnostics module — per-module health, faults, retries, voltage levels
• OPC UA server — exposes tags to SCADA, MES, IT systems out of the box
• Redundant CPU option — standby CPU on the same rail with bumpless transfer
• Cybersecurity — role-based access, signed firmware, audit log, optional VPN tunnel
• Cloud bridge — built-in MQTT client for sending tags to SGT or your own broker

Use Cases

• OEM machine builders — bottlers, packers, assemblers, converting lines
• Process plants — batching, mixing, dosing, CIP-SIP
• Material handling — conveyors, sortation, palletisers, AS/RS
• Building & infrastructure — HVAC, pump stations, water treatment, lighting
• Energy — substations, solar trackers, BESS controllers, gen-set ATS
• Retrofit & modernisation — replace obsolete S5 / S7-200 / SLC-500 / MicroLogix

Specifications

• CPU: ARM Cortex-A 1 GHz, 512 MB RAM, 4 GB flash, real-time Linux kernel
• Scan cycle: 1–10 ms configurable, <0.1 ms jitter
• I/O capacity: Up to 32 modules per rail, up to 4 racks (1024 I/O) per CPU
• Module types: 16/32 DI, 16/32 DO (relay/SSR), 4/8/16 AI (V/mA/RTD/TC), 4/8 AO, HSC 100 kHz, COMM
• Fieldbus: Modbus RTU/TCP, Profinet IO, EtherCAT master/slave, EtherNet/IP, OPC UA
• Compliance: CE, UL 508, IEC 61131-2, IEC 61508 SIL-2 variants, ATEX zone 2
• Environmental: −25 to +60°C, IP20 (cabinet-mount), 24 VDC ±20%
• Lifecycle: 15-year availability guarantee, 5-year hardware warranty

Product information

Customisation options

• CPU performance tier — entry (1 ms scan, 256 I/O), standard (1024 I/O), or redundant pair
• I/O module mix — pick any combination of DI, DO, AI, AO, HSC, RTD, TC, COMM up to 32 modules per rail
• Output type — relay (long life), solid-state (fast switching), or transistor sink/source for high-speed drives
• Fieldbus protocols — Modbus, Profinet, EtherCAT, EtherNet/IP, OPC UA, or BACnet for HVAC
• Safety rating — standard, SIL-2 (IEC 61508), or SIL-3 with safety I/O modules
• IDE & programming — ladder-first, ST-first, or full multi-language with library import
• Hosting / cloud — standalone, SGT cloud telemetry, or your own MQTT / OPC UA endpoint
• Service & support — 5-year hardware warranty, 24/7 phone, or on-site SLA contract

Ordering & lead time

Standard lead time depends on current stock. For volume orders, please contact our team for a structured quote including BOQ, freight, installation and warranty terms.

Support

Engineering support, installation guidance and warranty claims are handled by our customer success team. Reach us at support@sgtsystems.com or via the channels listed on our Contact page.