Triconex 3600 Series Modules | 3601T Digital Output Module

Technical Dossier

Product Details And Specifications

Triconex 3600 Series: Comprehensive Module Range and Technical Overview

The Triconex 3600 Series is a core component family within the Triconex Safety Instrumentation System (SIS) platform, developed by Invensys (now Schneider Electric). This series is deployed across the most demanding process safety environments globally, including petroleum refineries, LNG terminals, nuclear power auxiliary systems, offshore platforms, and large-scale chemical processing facilities. The 3600 Series occupies the I/O subsystem layer of the Tricon TMR (Triple Modular Redundant) architecture, providing fault-tolerant digital and analog signal interfacing between field instruments and the main processing unit. Its installed base spans hundreds of critical infrastructure sites across North America, the Middle East, and Asia-Pacific, making long-term parts availability a primary operational concern for plant engineers and reliability teams.

The Evolution of 3600 Series Architecture

The 3600 Series was introduced as part of the second-generation Tricon platform, succeeding the earlier 3000-series I/O modules. The architecture is built around the TMR principle: three independent processing legs (A, B, C) each receive identical field signals through separate I/O modules, with a voter circuit determining the valid output. This design tolerates single-point hardware failures without process interruption.

Early 3600 Series modules used parallel backplane communication with fixed-address slot assignment. Later revisions introduced enhanced diagnostics, improved HART pass-through capability on analog modules, and tighter integration with the Tricon Communication Module (TCM) for DCS gateway functions. The series is compatible with Tricon v9.x and v10.x Main Processors, and operates within the standard Tricon chassis (3700 Series baseplate). Compatibility with newer Tricon CX platforms requires adapter verification. As the 3600 Series has entered its mature/end-of-life phase for new procurement, the installed base remains active under long-term maintenance agreements, and replacement modules are sourced primarily through certified spare parts distributors.

3600 Series Full Catalog & Functionalities (SKU List)

The following SKUs represent verified, commonly deployed modules within the Triconex 3600 Series. Modules are classified by functional category:

Digital Output (DO) Modules

• 3601T: 32-channel 24 VDC digital output module, TMR-rated, solid-state relay outputs, field-side isolation, standard Tricon backplane interface.
• 3603T: 16-channel 120 VAC digital output module, TMR architecture, optically isolated, for high-voltage field device switching.
• 3604T: 16-channel 24 VDC digital output module, enhanced diagnostics, suitable for solenoid valve and relay driver applications.
• 3607T: 32-channel 24 VDC digital output module, high-density configuration, used in large-scale ESD and F&G systems.

Digital Input (DI) Modules

• 3664T: 32-channel 24 VDC digital input module, TMR, field-side isolation, used for discrete sensor and switch monitoring.
• 3665T: 32-channel 120 VAC digital input module, optically isolated, for AC field signal acquisition.
• 3666T: 32-channel 24 VDC digital input module, enhanced noise immunity, suitable for high-interference environments.
• 3667T: 16-channel 48 VDC digital input module, TMR, for legacy field wiring compatibility.

Analog Input (AI) Modules

• 3700A: 8-channel 4–20 mA analog input module, 12-bit resolution, TMR, HART-capable, used for pressure and flow transmitter interfacing.
• 3703E: 8-channel analog input module, enhanced resolution, supports HART protocol pass-through for smart transmitter diagnostics.
• 3704E: 8-channel analog input module, extended temperature range, for outdoor or non-climate-controlled marshalling cabinet installations.
• 3706A: 16-channel analog input module, high-density, 4–20 mA, used in large process variable monitoring applications.

Analog Output (AO) Modules

• 3805E: 8-channel 4–20 mA analog output module, TMR voted output, used for control valve positioner and variable speed drive setpoint signals.
• 3808E: 8-channel analog output module, enhanced current sourcing, for long cable run applications in remote field installations.

Communication & Specialty Modules

• 3625T: Pulse input module, 8-channel, for turbine flow meter and rotating equipment speed monitoring.
• 3636T: Thermocouple input module, 16-channel, supports J, K, T, E, R, S, B type thermocouples, TMR-rated.
• 3721T: Tricon Communication Module (TCM), Modbus RTU/TCP gateway, used for DCS integration and historian data exchange.

Sourcing Hard-to-Find & Obsolete 3600 Series Parts

Schneider Electric has formally transitioned new safety system sales to the Tricon CX and Triconex 3000 MP platforms. As a result, many 3600 Series modules are no longer available through standard OEM distribution channels. DriveKNMS maintains a dedicated inventory of tested, pull-out, and refurbished 3600 Series modules to support plant operators who require like-for-like replacements without system-wide upgrades.

DriveKNMS sources 3600 Series modules through decommissioned plant asset recovery, certified refurbishment programs, and direct procurement from verified industrial surplus channels. Each unit is catalogued by part number, hardware revision, and firmware compatibility level. For end-users operating under IEC 61511 or ISA 84 safety lifecycle requirements, DriveKNMS can provide documentation packages including test records and traceability data upon request.

Quality Control for the 3600 Series Range

The Triconex 3600 Series modules incorporate complex TMR backplane bus logic and field-side isolation circuitry that requires specialized test procedures beyond standard power-on verification. DriveKNMS applies the following test protocol to all 3600 Series units prior to shipment:

• Backplane connector inspection: pin integrity, contact resistance measurement, and mechanical alignment verification.
• Functional I/O test: each channel is individually stimulated and verified against expected output state using a Tricon-compatible test chassis.
• Isolation barrier test: field-side to logic-side isolation resistance measured at 500 VDC, minimum 100 MΩ required.
• Thermal cycling: modules are subjected to operational temperature cycling (0°C to 60°C) to identify latent solder joint or component failures.
• Firmware revision check: module firmware version is recorded and cross-referenced against known compatibility matrices for Tricon v9.x and v10.x systems.
• Final burn-in: 48-hour powered operational test under simulated load conditions before packaging.