Rockwell Automation T8471 Trusted TMR 120V dc Digital Output Module - 32 Channel - Manual (Page 9)

Trusted
TM
Module T8471
Issue 14 Apr 10 PD-T8471 9
Figure 2 shows a simplified block diagram of the Trusted TM 120V dc Digital Output module.
Figure 2 Functional Block Diagram
1.1. Field Termination Unit (FTU)
The Field Termination Unit (FTU) is the section of the I/O module that connects all three FIUs to a
single field interface. The FTU provides the Group Fail-safe switches and passive components
necessary for signal conditioning, over-voltage protection, and EMI/RFI filtering. When installed in a
Trusted
TM Controller or Expander Chassis, the FTU field connector interconnects to the Field I/O Cable
Assembly attached at the rear of the chassis.
The SmartSlot link is passed from the HIU to the field connections via the FTU. These signals go
directly to the field connector and maintain isolation from the I/O signals on the FTU. The SmartSlot
link is the intelligent connection between active and standby modules for co-ordination during module
replacement.
1.2. Front Panel Unit (FPU)
The Front Panel Unit (FPU) contains the necessary connectors, switches, logic, and LED indicators for
the front panel. For every module, the FPU contains the Slice Healthy, Active/Standby, the Educated
indicators (LEDs), and the module removal switches. Additional bi-colour LEDs provide status
indication for the individual I/O signals. Serial data interfaces connect the FPU to each of the HIU
slices to control the LED status indicators and monitor the module removal switches