I/O Modules, Tees & Disconnect Switches Often there is a need to connect conventional (non-bus) devices to a network. Our Input/ Output modules do just that by enabling users to connect conventional analog and discrete devices to their industrial fieldbus networks. I/O Modules allow users to cost-effectively use new or existing conventional devices in their fieldbus design. Wiring Tees make it easy to connect field devices to bus lines using wire terminals or plug-in connectors. Disconnect Switches enable users to repair or replace a field device, without disturbing the network, with the simple flip of a lever-operated switch. I/O Modules, Wiring Tees and Disconnect Switches are available as stand-alone products or inside HazLink connectivity enclosures.