Eldex Inputs/Outputs: I/O Functions are available on the connector on the rear panel. Inputs : The Optos can be remotely controlled from devices which can send current loop or voltage signals. in addition, the Optos can be remotely controlled using contact closures. see page 15 on our manual table 2.1 Outputs: Optos can send contact closures and an analog signal to remote devices. the remote outputs available are defined in Table 2.2 on page 17 of the manual.