Single line diagram

State: modelled. Run on the 109 public SCL files with a Substation section (652 elements; the vendor files have small substations, up to 6 elements). Every connection issue found was read and is a defect of its file. The view is read only.

Open the diagram

Open an SSD or SCD and run Open Single Line Diagram, or choose Reopen Editor With... > Single Line Diagram.

What is drawn

• Each voltage level is a row with its busbars.
• Each bay is a column under its busbar (or over it, when the bay is fed from a transformer of a level drawn above).
• The equipment of a bay is stacked in the order its terminals connect from the busbar side, with side branches (earthing switches, voltage transformers) beside.
• Power transformers sit between the levels they join, with the bays they feed lined up under them.
• An earth symbol marks every grounded terminal.
• IEC-style symbols for breaker, disconnector, earthing switch, current and voltage transformer, power transformer and line; other types are a box with their type code.

Positions come from the file's sxy:x and sxy:y coordinates when every element carries them, and from the module's own layout otherwise; the editor says which. Coordinates are read as grid cells of 64 drawing units.

Work with the diagram

1. Click an element or a busbar, or move with the arrow keys. The details show its path, type, position source, terminals and the logical nodes bound to it, each marked as in this file, IED not in the file, node not in its IED, or not assigned.
2. Reveal in Source or Enter opens the text at the element; a logical node opens at the node in its IED.
3. Zoom with the mouse wheel, + and -, or Fit; pan by dragging.

The drawing follows the text as you edit it.

Connection issues

Listed and opened at their place: terminals that name no node or a node the file does not have, equipment with no terminal, nodes nobody connects to, path names that disagree with their place, and duplicate paths.

Try it: a hand-written 132/33 kV station with a double busbar draws a 132 kV level with two busbars, a 33 kV level, transformer T1 between them, and breakers, disconnectors, CTs and VTs in their bays.

Size

The layout of 40 bays takes 6 ms and of 200 bays 27 ms once the file is read.

Limits

• Read only: the substation is edited in the text.
• sxy:dir is not read; symbols placed from the file are always drawn upright.
• A busbar is recognised by convention (a bay with connectivity nodes and no equipment).
• SubEquipment, GeneralEquipment, Function, TapChanger, NeutralPoint and the Edition 2.1 Line and Process sections are not drawn.

Not verified

• A substation of realistic size from a vendor tool, and how vendor tools write sxy coordinates.
• Ring bus, breaker-and-a-half and transformers joining three levels are untested and may cross wires.
• The drawing is checked by element counts and positions, not by image comparison.
• Windows.