Product Description

Model Number Interpretation

• 45C: Unified prefix for Reliance AutoMate 45C series control and I/O components.

• 224: Designates a 4-channel RTD temperature input module for AutoMate 20 systems.

• No revision letter indicates the original hardware version, optimized for standard RTD sensor compatibility.

Technical Specifications

• Input Channels: 4 isolated RTD input channels (2-wire or 3-wire connection).

• Supported Sensors: Pt100, Pt1000, Cu50, Cu100, Ni1000 (industrial standard thermal resistances).

• Temperature Range: -200°C to +850°C (Pt100, depending on sensor type).

• Resolution: 16-bit analog-to-digital conversion, 0.1°C typical resolution.

• Accuracy: ±0.1% of reading ±0.1°C (Pt100, 0–400°C range).

• Power Supply: 5 VDC from backplane, 0.8 A typical current consumption.

• Isolation: 2500 Vrms channel-to-backplane isolation for noise immunity.

• Operating Temperature: 0°C to 55°C; humidity 20%–90% non-condensing.

• Mounting: DIN-rail or panel mount via AutoMate 20 series backplane.

• Weight: ~0.9 kg; rugged metal enclosure for industrial durability.

Interface and Communication Configuration

• Sensor Input Terminals: 12-pin removable terminal block (3 pins per channel: R+, R–, compensation).

• Backplane Interface: Proprietary AutoMate 20 series edge connector for power and digital data exchange with the host CPU (e.g., 45C20A).

• Status LEDs:

  • PWR: On when 5 VDC backplane power is present.

  • RUN: Flashes during normal operation; steady on for fault.

  • CH1–CH4: On for active channel; flashes for sensor open/short circuit.

• Configuration: DIP switches for sensor type selection (Pt/Cu/Ni) and wire mode (2/3-wire) per channel.

Core Functions

• High-Precision Temperature Acquisition: Converts RTD resistance changes to accurate temperature data for process monitoring and control.

• Multi-Sensor Compatibility: Supports common industrial thermal resistance sensors with configurable 2/3-wire connections.

• Fault Detection: Monitors each channel for sensor open/short circuit, with LED indication and diagnostic codes for quick troubleshooting.

• Noise Filtering: Built-in digital filters to suppress electrical interference, ensuring stable measurements in harsh industrial environments.

• Data Integration: Transmits temperature data to the PLC CPU for PID control, data logging, and HMI display.

Application Scenarios

• Legacy AutoMate 20 Temperature Control Systems: Direct replacement for aging RTD modules in manufacturing lines.

• Process Automation: Widely used in food & beverage, pharmaceutical, chemical, and water treatment plants for temperature monitoring of tanks, pipes, and reactors.

• HVAC and Building Automation: Measures temperature in large facilities for climate control and energy management.

• Industrial Ovens/Furnaces: Precise temperature monitoring in heat treatment and metalworking processes.

• Retrofit Projects: Ideal for upgrading older AutoMate 20 systems to add temperature monitoring without full hardware replacement.

Usage and Maintenance Instructions

• Installation: Insert the module into an available slot on the AutoMate 20 backplane, ensuring secure connection; set DIP switches for sensor type and wire mode per channel.

• Wiring: Connect RTD sensors to the terminal block, using shielded cable; for 3-wire mode, ensure equal wire lengths for compensation accuracy.

• Power-On Check: Apply power to the backplane; confirm PWR and RUN LEDs are on, with no CHx fault indication.

• Routine Maintenance: Quarterly inspections; clean dust from terminal block and enclosure; check cable tightness and sensor connections; verify LED status during operation.

• Safety: Disconnect all AC power to the backplane and wait 5 minutes for discharge before servicing; avoid live maintenance; use only shielded RTD cables to minimize noise.