The Triconex 3351 serves as a core interface for triplicated safety systems, ensuring high availability and data integrity. Specifically, the module features 32 commoned input points designed for standard 4-20 mA DC signals. As a TMR module, the 3351 contains three completely isolated sets of electronics (channels). Each channel independently processes field data and transmits it to the Main Processors (MPs), where the data is voted. In TMR mode, the system utilizes a mid-value selection algorithm, while in dual mode, it transitions to an average. Therefore, the Triconex 3351 guarantees proper operation even in the presence of a single hardware fault.
Regarding technical precision, the module is engineered for rapid response and fine resolution. Specifically, the Triconex 3351 offers a 12-bit resolution with an absolute error of only 0.15% of the full scale. The internal circuitry achieves a scan time of less than 1 ms for all 32 points, making it suitable for fast-acting control loops. Furthermore, the module utilizes a specialized Force-to-Value Diagnostic (FVD) to verify the operational status of the analog-to-digital converters across all three channels. Consequently, the processor delivers a continuous and verified stream of process data to the application layer.
The Triconex 3351 is highly adaptable to various field requirements through its compatibility with multiple baseplate models. For instance, it can be used with the Model 2351 for standard applications or the Model 2354 for integrated HART communication. The HART-enabled baseplates allow for seamless communication between field devices and asset management software for remote calibration and diagnostics. Additionally, for hazardous locations, the module interfaces with specialized external termination panels. Therefore, the hardware provides a flexible foundation for both standard safety instrumented systems and advanced asset management architectures.
Regarding hardware performance, the Triconex 3351 operates within a specified operational current range of 2 mA to 22 mA. Specifically, the input impedance (including the baseplate) is 250 Ω, featuring a high-precision 100 Ω I-to-V resistor with 0.01% tolerance. Furthermore, the module provides robust electrical isolation of 800 VDC between logic and functional earth to prevent noise interference. In addition, the hardware includes an input bandwidth of 16 Hz (3dB) to filter out high-frequency field noise. These specifications allow the module to function effectively as a high-density, reliable monitoring unit in complex industrial racks.
Specifically, the Triconex 3351 features mechanical keying to prevent improper installation into a configured chassis. The module supports hot-spare functionality, enabling a secondary module to stay in a standby state for immediate takeover if the primary unit fails. Furthermore, the front panel includes a Fault indicator that activates if diagnostics detect a failure in any of the three internal channels. Besides its processing power, the module is designed to withstand an absolute maximum field voltage of 33 VDC. Finally, the total weight of 2.20 kg reflects the industrial-grade shielding and triplicated electronic components.
First, select the appropriate baseplate (e.g., Model 2351 for standard AI or 2354 for HART) based on your field device requirements. Next, align the Triconex 3351 with the mechanical keys on the baseplate and slide it into the slot until the connectors engage the triplicated backplane. After that, secure the module using the top and bottom locking levers to ensure a vibration-resistant connection. Furthermore, check the "ACTIVE" LED on the front panel to confirm that the module has successfully synchronized with the Main Processors. Finally, use the TriStation software to configure the input ranges and verify that the voted data values match your field transmitter readings.
1 x Triconex 3351 Analog Input Module (32-Point)
1 x Module Keying and Verification Tag
Shipping Carrier: Fedex, UPS, DHL
Q: Can the 3351 module communicate with HART field devices? Specifically, yes, when used with the Model 2354 or 2354A baseplates, the 3351 enables communication with HART transmitters.
Q: What happens to the data if one of the three channels fails? The module continues to operate; the system will automatically switch from mid-value voting (TMR) to averaging the data from the remaining two healthy channels.
Q: Is the 3351 suitable for high-speed control loops? Yes, the module features a scan time of less than 1 ms for all 32 points, providing the rapid feedback required for safety shutdowns.
Q: Does this module require a separate termination panel? It depends on your configuration; while it can use standard baseplates, it also supports External Termination Panels (ETP) for RTD/TC or hazardous locations.
Q: What is the maximum current the inputs can handle? The absolute maximum input current is rated at 50 mA DC, providing protection against field-side over-current conditions.
| Brand Name | Allen‑Bradley |
| Model No. | Triconex 3501T |
| Product Type | Solid-State Relay Output (SRO) |
| hasMerchantReturnPolicy | Adjust according to reality |
| Shippingdetails | Adjust according to reality |
