Triconex 3604E is TMR Digital Output Module. A TMR digital output (DO) module receives output signals from the main processors on each of three channels. Each set of three signals is then voted by special quadruplicated output circuitry on the module. The circuitry produces one voted output signal and passes it to the field termination. The quadruplicated voter circuitry provides multiple redundancy for all critical signal paths, guaranteeing safety and maximum availability.

Each TMR digital output module has a voltage-loopback circuit which verifies the operation of each output switch independently of the presence of a load and determines whether latent faults All TMR digital output modules support hot-spare capability, and require a separate external termination panel (ETP) with a cable interface to the Tricon backplane.