ICS Triplex T8402 Trusted TMR Digital Input Module

Configured for 24 VDC discrete field signal acquisition in the Trusted TMR Safety System, the ICS Triplex T8402 (T8402 Trusted TMR Digital Input Module) provides redundant input processing with continuous diagnostics. The module accepts field signals from switches and contacts, performs line monitoring, and transfers validated input states through the Trusted controller architecture.

Hardware Specifications

Trusted TMR Signal Processing and Diagnostics

The T8402 uses three independent input processing paths within the Trusted TMR architecture. The system applies 2-out-of-3 voting to input information before controller-level processing.

Each input path includes diagnostic monitoring for internal operating conditions and field line faults. Configurable open-circuit and short-circuit detection supports supervised discrete input circuits.

The module provides 500 VDC channel-to-bus opto-isolation between field input processing and the system bus. Input polarity and circuit configuration depend on the associated Field Termination Assembly.

Front-panel LEDs indicate module health, active status, and channel-level input states. These indicators support local identification of module and field signal conditions during commissioning and maintenance.

Frequently Asked Questions

Q: Can the T8402 be replaced while the Trusted system remains operational?
A: The supplied data specifies hot-swappable operation, allowing online module replacement without process interruption.

Q: What field voltage range does the T8402 accept?
A: The specified input range is 18 VDC to 32 VDC, with 24 VDC as the nominal input voltage.

Q: How does the T8402 process redundant input information?
A: The module uses Triple Modular Redundancy with three independent signal paths and 2-out-of-3 voting.

Field Installation Guidelines

Install the T8402 in the designated Trusted I/O Processor Chassis and verify mechanical engagement before energization.

Use the compatible T8800 series Field Termination Assembly for field wiring and signal termination. Confirm the selected FTA matches the required sinking or sourcing input configuration.

Route discrete signal wiring separately from high-voltage power conductors, switching circuits, and high-current motor wiring. Maintain appropriate physical separation according to the installation standard governing the control cabinet.

Terminate cable shields according to the project grounding design and avoid creating unintended shield current paths. Verify protective earth and signal reference arrangements before applying field power.

Check field polarity, supply voltage, termination points, and line-monitoring configuration before placing channels into service. Confirm open-circuit and short-circuit diagnostics under controlled commissioning conditions.

For hot-swap replacement, follow the Trusted system maintenance procedure and verify module identification, seating, status indication, and diagnostic state after installation.