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Generating the single-line diagram from your floor plan

In Volter you draw an installation once, on the plan. The single-line diagram is not a second drawing but a derivative: whatever you change on the plan or in the distribution board shows up on the diagram right away.

Why two separate drawings drift apart

The inspection asks for a floor plan and a single-line diagram of the same installation. Draw them separately, in a drawing program or by hand, and keeping them in step is up to you. Every change is made twice.

That is where the mistakes an inspector notices creep in: a socket outlet added on the plan but missing from the diagram, a circuit letter that no longer matches after a rearrangement, or a circuit with more points on the plan than on the diagram.

What Volter takes from the plan and the distribution board

From the floor plan:

  • which devices there are and which circuit they are on;
  • which devices share a branch, through the connections you draw, such as a switch with its light points;
  • how many identical devices follow each other: three or more become one symbol with the count next to it.

From the distribution board:

  • the circuit breaker of each circuit, with poles, curve, current rating and short-circuit capacity;
  • the cable, with type, CPR class, cores and cross-section, and the installation method;
  • which RCD each circuit sits behind, and which board feeds which other board.

The circuit letters follow the order on the rail. On the plan every device gets a reference such as C1 or C2: circuit C, branch 1 or 2. On site you see which point belongs to which branch of the diagram.

What you draw: the floor plan, with the devices where they go in the house.
What Volter makes of it: the single-line diagram of the main board. Light points C1, C2 and C3 on the plan are branches 1, 2 and 3 of circuit C.

What happens when you change something

  • You move a socket outlet from circuit B to circuit C. It leaves the column of B, appears on C, and its reference on the plan updates.
  • You connect an extra light point to a switch. It joins the branch of that switch.
  • You drag a breaker along the rail. The circuit letters shift, on the diagram and on the plan at the same time.
  • You delete a device on the diagram. Volter asks whether it should go everywhere or only from the single-line diagram. In the second case it stays on the plan, without a circuit.

Plan and diagram check each other

Because everything comes from one model, the AREI check makes connections you would have to spot yourself with two separate drawings. A room you mark as bath or shower on the plan requires a 30 mA RCD for every circuit going there. A device on the plan without a circuit is flagged, and so is a device you added on the diagram but not yet on the plan, because the AREI requires it on both. Which rules are checked is described under AREI validation.

Questions from installers

Can I still edit the generated single-line diagram by hand?

Not by dragging symbols or drawing lines. You change the source: the circuit assignment and connections on the plan, or the breaker and cable in the distribution board. You change the order of the circuits by dragging the breakers along the rail. That way the diagram always matches the plan.

Why is a device on the plan but not on the single-line diagram?

Because it is not on a circuit yet. The diagram only shows devices with a circuit. The Assign components button at the top of the single-line diagram counts how many devices are still waiting and takes you to the plan, and the AREI check flags every device without a circuit.

Do the circuit letters change if I add a circuit later?

Only if you put it between existing circuits. The letters follow the order of the breakers on the rail, row by row. Put the new breaker at the end of the last row and it gets the next letter while the others stay put. Slide it in between and the letters after it shift, on the plan and on the diagram at the same time. A sub-board does not touch the letters of the main board: its circuits get the board code in front.

Does the bill of materials match the diagram?

Yes. The bill of materials in the PDF counts every symbol per storey and per room, from the same model as the diagram. Devices you added on the diagram and have not placed on the plan yet appear under Not yet placed.

Read on

Try it on the demo home

In the demo home, move a socket outlet to another circuit and see where it ends up in the Single-line diagram tab. You don't need an account, and nothing you change is saved.

Try the demo homeSee pricing

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