TRICONEX AI6700 Analog Input Module

I. Overview

It is designed in strict compliance with the IEC 61508 functional safety standard (supporting up to SIL 3 level) and has three core advantages compared with ordinary high-density DI modules:

1. High-density redundant acquisition: A single module integrates 32 independent channels, each supporting TMR triple acquisition, balancing the number of measurement points and safety redundancy;

2. Hardware-level full-channel fault diagnosis: Built-in open-circuit, short-circuit, and channel drift detection circuits with a diagnostic coverage rate of ≥99.5%, enabling real-time localization of single-channel abnormalities;

3. Industrial-grade harsh environment adaptation: Adopting wide-temperature design, enhanced anti-interference capability, and corrosion-resistant materials, it is suitable for high-temperature, strong electromagnetic interference, and high-humidity scenarios. The Mean Time Between Failures (MTBF) reaches more than 2.2 million hours, making it a core acquisition component for multi-measurement-point safety monitoring scenarios.

II. Technical Parameters

1. Basic Specifications

2. Performance Parameters

Signal Acquisition Characteristics

Redundancy and Safety Characteristics

• TMR Redundant Architecture: Each input signal corresponds to three independent photoelectric isolation circuits, signal conditioning units, and status detection channels. The collected data is processed by the system's "2oo3" voting logic (valid results are output if the states of any two channels are consistent). A single-channel fault (such as damage to the optocoupler) does not affect the overall signal acquisition, and the remaining two channels still maintain normal voting;

• Fault Diagnosis Capability: Capable of detecting 7 types of faults, including "channel open circuit" (no signal for dry contact, wet contact voltage

• Safe Output State: When the module detects a severe fault (such as simultaneous failure of two channels or abnormal overall power supply of the module), a single channel automatically outputs a "fail-safe value" (presettable to "0" or "1", default "0", corresponding to the "equipment shutdown/interlock triggered" state) to ensure the correct action of downstream safety logic.

Anti-interference and Isolation Characteristics

• Photoelectric Isolation: The signal circuit of each channel and the internal logic circuit of the module adopt photoelectric isolation (isolation voltage 2500V AC for 1 minute) to prevent external signal interference from propagating to the system core;

• Electromagnetic Compatibility (EMC): Radiation emission complies with EN 55022 Class B standard; immunity complies with EN 61000-6-2 standard (Electrostatic Discharge ±8kV contact/±15kV air, Electrical Fast Transient ±2kV, Surge ±4kV);

• Power Isolation: The 24V DC signal power supply and +5V DC logic power supply adopt an independent isolation design (isolation voltage 1500V DC) to prevent mutual interference from power fluctuations (e.g., 24V fluctuations do not affect the stability of the logic circuit).

III. Functional Features

1. High-density Redundant Acquisition and Safety Voting

• 32-channel Independent TMR Acquisition: The module integrates 32 channels in a compact size, and each channel is equipped with three independent optocouplers and signal processing circuits. For example, when collecting the "running/stopped" status of 32 pumps, the contact signal of each pump undergoes "2oo3" voting after being collected by three channels. Even if one acquisition channel fails, the real status can still be confirmed through the other two channels, avoiding misjudgment caused by a single-point fault (such as mistakenly judging "stopped" as "running"). At the same time, it meets the space-saving requirement for multi-measurement-point scenarios (reducing 1 slot occupation compared to 2 16-channel DI modules);

• Channel Group Management: Supports grouping 32 channels by function (e.g., "Pump Group 1-8 Channels", "Valve Group 9-16 Channels") via TriStation 1131 software. Parameters such as debounce time and fail-safe value can be configured by group to adapt to different types of on-site equipment (e.g., setting 100ms debounce for pump channels with frequent vibration, 10ms debounce for stable valve channels), simplifying the parameter configuration process;

• Fault Isolation and Channel Disablement: When a fault (such as a short circuit) is detected in a channel, the module automatically marks the channel as "faulty" and isolates it without affecting the operation of other channels in the same group. It also supports manual disablement of faulty channels (e.g., standby measurement points with long-term faults) via software to prevent them from occupying system resources or triggering invalid alarms.

2. Full-dimensional Fault Diagnosis and Intelligent Alarm

• Hardware-level Real-time Fault Detection: Built-in independent fault detection circuits, each channel monitors the signal state and its own health status in real time. For example, when a wet contact channel detects a current >150mA, it is determined as a "short-circuit fault", triggers the channel status light to flash red within 50ms, and sends a fault code (e.g., F05 = Channel 5 Short Circuit) to the HMI. When a dry contact channel detects no signal but the cable continuity is normal, it is determined as "equipment not activated", avoiding false alarms of "open-circuit fault" and improving diagnostic accuracy;

• Hierarchical Alarm Mechanism: Supports hierarchical alarms based on fault severity (e.g., "channel fault" is a local alarm, only prompting maintenance personnel for handling; "24V power supply abnormality" is a global alarm, triggering a system-level early warning). At the same time, the HMI displays the fault channel location, fault type, and occurrence time, facilitating quick localization (e.g., "Channel 22 Open Circuit" directly points to the on-site equipment corresponding to Channel 22);

• Fault Logging and Tracing: Supports storage of up to 200 fault records (including channel number, fault type, signal value at the time of fault, and recovery time). Logs are stored in power-off protected flash memory (no battery required) and can be exported as Excel files via software for fault root cause analysis (e.g., counting frequent open circuits of channels in a certain area to investigate cable laying environment issues).

3. Industrial-grade Reliability and Environmental Adaptation

• Wide-temperature and Harsh Environment Resistance: The operating temperature range of -40°C ~ 70°C covers outdoor cabinets in cold regions (e.g., SIS cabinets at wellheads of northern oilfields) and areas near high-temperature equipment (e.g., beside heaters in refining units), without the need for additional temperature control equipment. The PCB adopts a military-grade conformal coating (moisture-proof, corrosion-proof, dust-proof), extending the service life to more than 12 years in the humid environment (95% RH, no condensation) and oil-gas-rich scenarios of petrochemical workshops;

• Enhanced Anti-interference Design: Dual protection of photoelectric isolation for signal circuits and independent isolation for power supplies, which can resist electromagnetic interference generated by frequency converters and high-voltage motors in industrial sites (e.g., no false state transitions of 32 channels under ±2kV electrical fast transient interference). The module housing is made of flame-retardant ABS material (UL94 V-0 grade), which self-extinguishes when exposed to fire, meeting industrial fire protection requirements;

• Durable Material Selection: Uses long-life industrial-grade optocouplers (service life ≥100,000 hours @40°C), gold-plated terminals (plugging/unplugging times ≥1000, contact resistance<50mΩ), and a 2A self-resetting fuse built into the 24V power supply circuit to prevent module burnout due to overcurrent. The Mean Time Between Failures (MTBF) is ≥2.2 million hours, meeting the requirements of high-reliability scenarios.

4. Convenient Operation & Maintenance and Compatibility

• Visual Status Monitoring: The front panel is equipped with 32 channel status lights (green steady on = "1" state, green off = "0" state, red flashing = channel fault) + 2 power lights (yellow = +5V normal, blue = 24V normal) + 1 redundancy status light (white steady on = TMR normal). The status of each channel can be intuitively judged without accessing software (e.g., red flashing of Channel 10 indicates a fault in that channel). The channel lights are arranged in groups of 8 for easy quick localization;

• Remote Configuration and Testing: Channel parameter configuration (type, debounce time, fail-safe value) and "channel testing" (software-forced input of "1"/"0" signals to verify downstream logic response) can be completed remotely via TriStation 1131 software, without on-site module disassembly or equipment wiring disconnection (e.g., testing Channel 25 corresponding to the "emergency stop button" without pressing the actual button);

• Spare Part Compatibility and Hot-swapping: Compatible with other high-density DI modules in the TRICON series (e.g., DI6502), with consistent module size, interface definition, and communication protocol, enabling direct replacement and reducing spare part inventory costs. Some TRICON racks support hot-swapping, allowing module replacement without power-off, and the system maintains TMR operation to avoid production interruption.

IV. Operation, Maintenance and Troubleshooting

Daily Maintenance Points

• Status Monitoring: Check the module's operating status via the TRICON HMI daily to confirm that the status of 32 channels is consistent with on-site equipment (no abnormal "1"/"0") and there are no fault alarms. Inspect the indicator lights on-site to ensure the power lights and redundancy light are steady on, and no channel lights are flashing red. Focus on channels corresponding to key equipment (such as the emergency stop button channel);

• Wiring and Power Supply Inspection: Monthly check the 24V signal power supply terminals of the module and the wiring of 32 channels (especially the tightness of terminal block screws), and re-tighten the screws (torque 0.5-0.8N·m) to avoid loose wiring caused by vibration (increased contact resistance leading to false open-circuit alarms). Measure the 24V power supply voltage to ensure it is within the range of 22V ~ 26V DC, with a fluctuation ≤±5%;

• Debounce and Fault Testing: Quarterly perform "channel debounce testing" (simulating contact bounce signals to verify whether the module filters correctly) and "fault injection testing" (simulating channel open-circuit/short-circuit to verify whether alarms are triggered) via software. Increase the testing frequency (once a month) for key channels (such as safety interlock contacts);

• Environmental Control: Ensure the temperature inside the cabinet is within the range of -40°C ~ 70°C. Regularly clean the dust from the module's heat dissipation holes (blow along the heat dissipation direction with compressed air, avoiding vertical blowing to prevent dust from entering the interior). Check the cabinet's sealing to prevent oil, gas, and dust from entering the module terminals and affecting contact performance (e.g., in petrochemical workshops, check the terminal oxidation status quarterly and wipe with alcohol cotton).

Common Faults and Solutions