Module operation – Rockwell Automation T3446H ICS Regent Relay Output Modules User Manual
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Relay Output Modules (T3446L, H)
2
Industrial Control Services
Module Operation
A block diagram of a typical relay output module is shown in
Figure 1.
The processor modules send triplicated write data commands
to the output module over the I/O Safetybus. The processors’
addressing data and data write commands are voted by the
module (preventing I/O Safetybus failures upstream from the
module from affecting module operation). The voted result is
then passed to the I/O bus interface logic.
Figure 1. Block Diagram of a Relay Output Module.
The voted output data from the I/O bus interface logic is then
used to drive the output circuits. Logic output drive signals
energize the coils of relays mounted on the printed circuit
board. Relay contacts provide dry-contact switching of load
devices.
When the output is logically turned on, the relay coil is
energized (closing the N.O. contact), and when the output is