Description
TRICONEX 3625A | 24 VDC Digital Output Module | TMR Safety System
Key Technical Specifications
| Parameter | Specification |
|---|---|
| Product Model | 3625A |
| Manufacturer | Triconex / Schneider Electric |
| Product Type | Digital Output Module |
| Output Type | 24 VDC digital |
| Number of Outputs | 32 points |
| Architecture | TMR |
| Output Configuration | Commoned |
| Operating Voltage | 16–32 VDC recommended |
| Nominal Voltage | 24 VDC |
| Maximum Voltage | 36 VDC |
| Maximum Current | 1.70 ±10 A per point |
| Surge Capability | 5 A for 7 ms |
| Total Module Output Current | 10 A per termination panel |
| Minimum Required Load | 10 mA |
| Maximum Output Leakage | 2.0 mA at 24 VDC; 2.5 mA at 32 VDC |
| Logic Power | Less than 13 W |
| System-to-Field Isolation | 1,500 VDC minimum |
| Output Supervision | Programmable per point |
| Short/Open Detection | Programmable on supervised points |
| Output Toggle Rate | One change every 60 ms |
| Protection | Self-protected output switches |
| Compatible System | Tricon v10.2 and later |
The published Tricon specification identifies the 3625A as a 32-point TMR supervised or non-supervised digital output module for energize-to-trip and de-energize-to-trip applications. The output circuitry includes diagnostics and self-protection against over-voltage, over-temperature, and over-current conditions.
The defining hardware difference between 3625 and 3625A is field-power distribution. The original 3625 has field power commoned across all points, while the 3625A separates field power into two 16-point groups while maintaining a common return. Schneider/Invensys documentation states that the 3625A remains compatible with applications using the 3625.
Product Introduction
The TRICONEX 3625A is a 32-point 24 VDC digital output module for Tricon safety systems. It provides the output interface between the TMR safety controller and field devices such as solenoids, relays, alarms, and other discrete actuators used in shutdown and critical-control functions. Its three-channel architecture supports the fault-tolerant design of the Tricon platform.
This module is intended for both supervised and non-supervised output applications and can support either energize-to-trip or de-energize-to-trip logic. The field-power arrangement is particularly important during replacement because the 3625A divides the 32 outputs into two separately powered groups of 16.
3625A
Application Scenarios & Field Pitfalls — Engineer’s Perspective
Engineering Pain Point
The 3625A is frequently treated as a simple 24 VDC output card. That is a mistake in a safety system. The termination panel, field-power arrangement, supervision configuration, output loading, and Tricon controller version all affect whether the module is suitable for the installed application.
Typical Applications
- Emergency Shutdown Systems — driving final elements and shutdown solenoids.
- Process Safety Systems — controlling discrete safety-related actuators and alarms.
- Fire and Gas Systems — interfacing safety logic with discrete field equipment.
- Turbine and Compressor Protection — providing discrete trip and permissive outputs.
- Energize-to-Trip / De-energize-to-Trip Circuits — supporting both common safety output philosophies.
Technical Pitfalls to Avoid
- Do not confuse 3625A with a digital input module.
The 3625A is a digital output module. Some current product pages incorrectly identify it as a high-density digital input card. The Tricon system documentation explicitly classifies 3625A under Digital Output Modules. - Check the Tricon system version.
Schneider/Invensys documentation states that the 3625 and 3625A can be installed only in Tricon v10.2 and later systems. Do not assume compatibility with an older Tricon chassis simply because the module fits physically. - Pay attention to the 16-point field-power groups.
The 3625A divides field power into two groups of 16 outputs. Documentation recommends wiring the termination panels in parallel and powering them from the same redundant field-power sources. If multiple independent sources are used, their voltages must remain within 5% of the highest supplied voltage or voter faults and alarms may occur. - Do not select the module based only on 24 VDC.
The output can handle up to approximately 1.7 A per point under the specified conditions, but actual suitability depends on load type, cable resistance, termination hardware, supervision requirements, and the application’s trip philosophy. - Check the termination panel before replacement.
The 3625A is designed for 16-point commoned termination panels. The termination architecture is part of the installation and should be checked together with the output module rather than treating the module as an isolated spare.
Related Products
- 3625 — Earlier 32-point 24 VDC TMR digital output module. The 3625A modifies field-power distribution while retaining application compatibility with the 3625.
- 3624 — 16-point 24 VDC TMR supervised/commoned digital output module.
- 3604E — 16-point 24 VDC TMR non-commoned digital output module.
- 3603E/T — 16-point 120 VDC TMR commoned digital output module.
- 3607E — 16-point 48 VDC TMR non-commoned digital output module.
- 3614E — 8-point 24 VDC TMR supervised/commoned digital output module.
- 3664 — 32-point 24 VDC dual-output module for applications using a different redundancy arrangement.
- 3674 — Related 32-point 24 VDC dual-output module.
- 3807 — 4-point bipolar analog output module; different signal type and application.
- 3902AX — 16-point universal I/O/HART TMR module with AI/DI/DO/AO functionality; not a direct 3625A substitute.
Procurement Note
For a TRICONEX 3625A replacement, specify the complete 3625A model and confirm the installed Tricon version, termination panel type, supervised/non-supervised configuration, energize-to-trip or de-energize-to-trip philosophy, and field-power arrangement.
For used or surplus stock, inspect the connector pins, front-panel indicators, module housing, termination interface, and evidence of heat damage around the output circuitry. A power-up test alone does not prove that all 32 channels, diagnostics, supervision functions, and field-load interfaces are operating correctly.
The most important procurement distinction is simple: 3625A is a 32-point 24 VDC TMR digital output module, not a digital input module and not a standalone Tricon controller.
