SAIA PCD4.H420｜Programmable Logic Controller｜

Key Features

Mid to High Computing Performance
Equipped with a 32-bit industrial-grade CPU supporting multitasking parallel processing (logic control, data acquisition, communication protocol parsing). Basic instruction execution time ≤ 1 µs, ideal for moderately complex scenarios such as multi-loop PID regulation and high-speed counting.

Flexible Scalability
CPU module separated from I/O, communication, and special-function modules. Digital, analog, and temperature acquisition modules can be expanded on demand without bottlenecks, balancing current needs with future upgrades.

Industrial-Grade Stability
Wide temperature range (–25 °C to +70 °C), EMC compliance (IEC 61000-6-2/6-4), vibration resistance (IEC 60068-2-6). MTBF > 100 000 h makes it suitable for harsh workshops and outdoor control cabinets.

Mainstream Communication Integration
Built-in industrial communication interfaces allow direct connection to HMI, drives, and upper-level systems without extra modules. Expansion for high-end buses (PROFINET, EtherCAT) ensures compatibility with both legacy and new network architectures.

Basic Special Functions Built-In
Integrated PID process control, high-speed counting, and other functions support moderately complex control tasks (temperature closed-loop regulation, equipment positioning) without dedicated modules, reducing initial investment.

Key Technical Parameters

Core Performance

Processor: 32-bit industrial CPU, 8 priority tasks, ≤ 1 µs basic instruction time

User Memory: 1 MB standard (program + data); expandable to 4 MB flash for backup/historical data

Real-Time Clock: Built-in lithium battery backup RTC, ±1 minute/month; supports NTP synchronization (Ethernet required)

I/O Expansion Capability

Central I/O Points: Up to 512 (PCD4 dedicated I/O modules)

Remote Expansion: Profibus DP (master/slave) and Modbus RTU/TCP (master) for remote I/O; up to 2048 remote points

Supported Modules: Digital DI/DO (standard/high-speed up to 100 kHz counting), Analog AI/AO (12–16 bit), Temperature (PT100/thermocouple with cold-junction compensation)

Integrated I/O Channels

Digital: 12 DI (24 VDC, PNP/NPN configurable, supports interrupts); 6 DO (24 VDC, 0.5 A/point, PWM capable)

Analog: 6 AI (4–20 mA/0–10 V, software-configurable range, 12-bit); 1 AO (4–20 mA/0–10 V, 12-bit)

Communication Interfaces

Serial Ports: 3 configurable RS-232/RS-485 (Modbus RTU, SAIA PCD Link, ASCII) for HMI, instruments, drives

Industrial Bus: Built-in Profibus DP slave (optional module upgrade to master)

Ethernet: 1 × 100 Mbps port (TCP/IP, Modbus TCP; optional PROFINET IO slave module)

Extended Support: CANopen and EtherCAT modules optional to fit different industrial buses

Special Functions

Process Control: 16 built-in PID loops (self-tuning, feed-forward, adaptive closed-loop for temperature, pressure, flow)

High-Speed Counting: 2 integrated counters up to 50 kHz (pulse counting, frequency measurement, phase difference detection)

Data Recording: Supports SD card module for historical data storage (configurable 10 ms–1 h) for fault tracing/trend analysis

Event Recording: Automatic I/O status and fault log with time stamps for diagnostics

SAIA PCD4.H420｜Programmable Logic Controller｜