Create backup and off-grid supplies

Add an inverter, battery, and solar panels, then draw an emergency circuit, full changeover, or phase-split inverter group.

Use this workflow to draw an inverter as part of the supply. You can extend the same basic arrangement with DC sources, one dedicated emergency circuit, or a source transfer switch for the complete installation.

The one-wire diagram automatically groups an extended supply path in the Supply frame. Read The supply frame for an overview of what that frame represents, when it appears, and how the grid and backup busbars relate.

Document the real installation

Condui draws the selected topology, but does not determine whether devices may operate together or how protection, earthing, and changeover must be implemented. Always check the manufacturer's documentation and the installation design.

Choose the intended arrangement

Add an inverter as a supply

1. Open the One-wire diagram and find Inverter (DC → AC) in the symbol library.
2. Drag the inverter onto the main supply wire of the intended panel.
3. Drop it when the blue preview shows the separate inverter branch.
4. Select the inverter and choose the phase or phases it uses under AC phases.
5. Enter the brand, model, power, and serial number where needed.

In this basic arrangement, the inverter remains connected to the grid. Placing it on the supply wire does not by itself turn it into a full off-grid supply.

Add solar panels and a battery

After placing the inverter, DC connections appear beside the inverter branch.

1. Drag Solar panel onto one free DC connection.
2. Drag Battery onto the other DC connection.
3. Check the direction of the connections and complete the properties of each device.

Solar panels and batteries added here belong directly to the supply arrangement. This differs from placing a solar panel or battery as a normal endpoint on a circuit.

Supply one emergency circuit

Use this arrangement when only selected loads must remain powered during a grid outage.

1. First place the inverter on the main supply wire.
2. Drag suitable protection, such as an MCB or RCBO, onto the free backup output on the left of the inverter.
3. Condui creates a separate circuit supplied directly by the backup output. This circuit is not connected to the main bus.
4. Add the emergency loads to that circuit.
5. To group several emergency circuits, drag a Distribution panel onto the circuit to turn it into a dedicated backup panel.

The backup circuit inherits the inverter's selected AC phases. Check the inverter phase setting first, followed by the poles, cable, and protection of the emergency circuit.

At present, one protected backup circuit or one backup panel can be connected to this separate output per inverter.

Change over the complete installation

Use a source transfer switch when the same installation downstream of the switch must be supplied entirely by either the grid or the backup source.

1. Place the inverter on the main supply wire as described above.
2. Find Source transfer switch in the symbol library.
3. Drag the switch onto the indicated supply position between the grid and backup sources and the panel.
4. Condui connects the grid input and the inverter's backup output to the switch's two inputs.
5. Select the switch to edit its label and the names of port 1 and port 2.
6. Check that every conductor required in backup operation is actually switched.

You can also place the source transfer switch first and then drag the inverter onto its free backup branch. Both sequences create the same kind of supply arrangement.

Emergency circuit or full changeover?

Use the separate backup output for a limited emergency circuit or dedicated backup panel. Add the source transfer switch only when the supply downstream of it must change over as one whole between the grid and backup source.

One inverter or three inverters across the phases

In a three-phase installation, one single-phase inverter can supply one selected phase. For three coordinated single-phase units, such as a possible Victron MultiPlus-II configuration, Condui can represent one group as three physical inverters.

One unit on one phase

1. Select the inverter.
2. Under Properties > AC phases, select the phase in use, for example L1 + N.
3. Check that the backup circuit or changeover follows the same phase distribution.

Three units on three phases

1. Open the inverter's context menu and choose Add more....
2. Set the total count to 3.
3. Condui treats the group as three physical units and distributes them over L1, L2, and L3.
4. Enter each unit's serial number and check the three placements on the situation plan.
5. Check the group's shared brand, model, and power in its properties.

Use 3 only when the manufacturer supports the devices as one coordinated three-phase group. Three independent inverters do not automatically form a valid three-phase backup installation.

Finish and check

1. Check the phase choice of every inverter and the poles of protections and changeover switches.
2. Complete cable data, device data, and recognizable labels.
3. Review the one-wire diagram and the situation-plan placements.
4. Open AREI Validation and assess every message in the context of the real design.
5. Only then export the PDF.

See Advanced one-wire workflows for secondary panels, secondary buses, and other conversion devices.