Trusted 40 Channel Analogue or Digital Output FTA

The Trusted® 40 Channel Analogue Output or Digital Output Field Termination Assembly (FTA) is designed to act as the main interface between the Trusted Triple Modular Redundant (TMR) 24 Vdc Digital Output Module T8451, Trusted Triple Modular Redundant (TMR) 24/48 Vdc Digital Output Module T84611 or Trusted TMR Analogue Output Module T8480 and the field device.

TMR Fault Detection/Testing

Extensive diagnostics provide the automatic detection of Module faults. The TMR architecture of the Output Module and the diagnostics performed verify the validity of all critical circuits. Using the TMR architecture provides a Fault Tolerant method to withstand the first fault occurrence on the Module and continue normal output controls without interruption in the system or process. Faults are reported to the user through the Healthy status indicators on the Front Panel of the Module and through the information that is reported to the TMR Processor. Under normal operations, all three Healthy indicators are green. When a fault occurs, one of the Healthy indicators flashes red. It is recommended that this condition is investigated and if the cause is within the Module, it should be replaced.

Module replacement activities depend on the type of spare Module configuration that is chosen when the system was configured and installed. The Module may be configured with a dedicated Companion Slot or with a SmartSlot for a spare replacement Module.

From the IMB to the field connector, the I/O Module contains extensive fault detection and integrity testing. As an output device, most testing is performed in a non-interfering mode. Data input from the IMB is stored in redundant error-correcting RAM on each slice portion of the HIU. Received data is voted on by each slice. All data transmissions include a confirmation response from the receiver.