Product Description:

The X20DO4633 is a digital AC output module produced by B&R Automation for the X20 Fieldbus Input Output Modules series. Within a distributed control cabinet, it installs on the X20 backplane to switch external single-phase loads such as contactors, small heaters, or indicator lamps that run directly from the mains. Incorporating this module lets an automation controller send discrete commands to equipment while keeping high-voltage wiring on the field side and low-voltage logic on the bus side.

This unit provides 4 outputs, giving the PLC four independent points for load actuation. Each channel uses a solid-state Triac, so there are no moving parts and switching wear remains minimal. A continuous load of 1 A per channel can be driven without derating, enabling direct connection of modest resistive or inductive devices. The triac circuitry supports a maximum line potential of 240 VAC and remains conductive down to a minimum of 48 VAC, allowing the same module to be used on 120 V or 230 V installations without hardware changes. Because all outputs share a common reference, wiring is straightforward, and zero-cross switching reduces electromagnetic interference during turn-on.

The firing algorithm is based on phase-angle control, so the controller can modulate the conduction angle when proportional power delivery is required. Internally, the outputs follow the L-switching convention, meaning the live conductor is interrupted while the neutral remains continuous. Module identification in the rack uses a keyed supply of 240 V; only slots delivering this voltage will accept the carrier, which helps prevent accidental misplacement. The module uses the same mechanical form factor as other X20 slices, and field-removable terminal blocks allow wiring to be detached at the terminal block.