Mitsubishi Electric FX5-4LC MELSEC iQ-F Series Temperature Control Module

Description

Directly executing loop control functions for the MELSEC iQ-F bus, the Mitsubishi Electric FX5-4LC acts as an autonomous multi-channel temperature processor. This module offloads processing overhead from the main CPU, executing high-precision PID and cascade algorithms directly on board to maintain strict temperature and process parameter tolerances. Supporting up to four independent channels, it accommodates a broad range of thermocouple and resistance temperature detector (RTD) inputs for heavy industrial environments.

Features

• Multi-Loop Control: Supports independent PID control, heating/cooling PID control, cascade control, and standard two-position regulation across four loops.
• Input Flexibility: Direct interface compatibility with standard industrial thermocouples and RTD sensors.
• Integrated Outputs: Equipped with four dedicated transistor outputs to drive solid-state relays or external actuator devices.
• Optimized Bus Integration: Occupies only 8 digital I/O points on the MELSEC iQ-F CPU backplane, preserving physical PLC space.

Applications

• Plastic extrusion and injection molding heating zones.
• Industrial baking, curing, and thermal treatment furnaces.
• Packaging equipment heat-seal bar control.
• Environmental testing chambers and climate control units.

Technical Specifications

Empirical Engineering Insights

Alternative Models & Compatibility

The FX5-4LC is designed exclusively for the MELSEC iQ-F (FX5U / FX5UC) expansion bus. Unlike older FX3U analog modules, it cannot be directly integrated into legacy FX3U bases without an conversion adapter bus, and GX Works3 is required to configure its hardware profile parameters.

Application Pitfalls & Engineering Notes

When using RTD sensor configurations, ensure that any cable resistance differences across leads do not exceed standard line limits. Unequal line impedances on the 3-wire RTD input will manifest as persistent temperature measurement offsets, degrading PID loop accuracy.

Commissioning & Wiring Tips

To mitigate high-frequency electrical noise from nearby variable frequency drives (VFDs) or heater switching elements, shield all thermocouple and RTD signal cabling. Ground the shield at a single point on the control panel chassis, and keep low-voltage sensor lines physically segregated from high-current power conduits.

Installation Guidelines