Product Overview

The AH04TC-5A (AH04TC5A) is a high-performance 4-channel temperature measurement module designed for the Delta AH500 modular PLC system. This module is engineered for high-precision thermal monitoring and control in demanding industrial processes such as plastic extrusion, heat treatment, and chemical reactors. It supports a wide range of thermocouple types (J, K, R, S, T, E, N) and low-voltage signals (±150mV) with an effective 16-bit resolution. The AH04TC-5A is built for mission-critical reliability, featuring hot-swapping capabilities, signal isolation, and a built-in PID control function, allowing it to manage temperature loops independently of the main CPU's scan cycle.

Technical Configuration

The hardware of the AH04TC-5A is designed for maximum signal integrity and system uptime. It utilizes a JIS removable terminal block, which simplifies maintenance and field wiring. The module provides a fast conversion time of 200ms per channel, ensuring responsive data acquisition for dynamic temperature changes. Its isolated signal design protects the internal PLC backplane from field-side electrical interference. Advanced diagnostic capabilities are integrated, including disconnection detection to immediately alert operators if a thermocouple probe fails, and module status LEDs for instant local troubleshooting.

Technical Specifications

Technical FAQs

Does the AH04TC-5A support Cold Junction Compensation (CJC)?

Yes. To maintain high accuracy, the module includes internal cold junction compensation to account for the temperature at the terminal block where the thermocouple wires connect. This ensures that the voltage-to-temperature conversion remains precise across varying ambient conditions.

What is the benefit of the "Hot-swapping" function in the AH500 series?

The AH04TC-5A is designed for high-availability systems. Hot-swapping allows you to replace a faulty temperature module without powering down the entire PLC rack or stopping the process. This is critical for continuous manufacturing lines where downtime results in significant material loss.

How does the PID function work within the module itself?

Instead of the PLC CPU performing all PID calculations, the AH04TC-5A can be configured to handle PID loops locally. This reduces the processing load on the main CPU and ensures that temperature control continues smoothly even if the CPU scan time increases due to complex logic elsewhere in the program.

Engineering & Installation Guide

• Thermocouple Wiring: When wiring the 4 channels, always use the correct compensation wire for the specific thermocouple type being used. Mixing wire types or using standard copper wire will introduce significant measurement errors. Ensure that the polarity (Positive/Negative) is strictly observed at the JIS terminal block.

• Noise Mitigation: To achieve the rated ±0.6% accuracy, keep thermocouple leads away from high-voltage AC power lines and Variable Frequency Drives (VFDs). If the environment is electrically noisy, utilize the module's built-in digital filtering settings via the AH500 configuration software.

• Disconnection Detection: Enable the "Disconnection Detection" function in the module parameters. This will allow the PLC to trigger a safety routine (such as shutting down heaters) immediately if a sensor wire is broken, preventing uncontrolled heating.