Building a diagram from the plant
Generate: Automatic draws a starter single-line diagram from the layout, the ACCB & Transformer grouping and the inverter file; Full SLD expands it to one row per feeder.
Generate: Automatic on the SLD TOOLS panel draws a starter single-line diagram — SLD — from the plant you have already laid out. It reads the layout's equipment counts, the electrical grouping — the combiner boxes, the transformers, their ratings and voltages, as the ACCB & Transformer card produces them — and the inverter file, then places the chain from the modules through to the grid and annotates each block with how many of that item there are and what it is rated at. What you get is a correct-by-count skeleton on the drawing sheet, which you then edit.
It never reads the bill of materials. Editing the materials list, rebuilding it or loading a template cannot change the diagram.
It is a starting point, not a finished drawing. The chain it places is the generation-to-grid path; the protection, switching and instrumentation an issued SLD carries is drawing work you do on top of it.
Before you run it
The automatic build reads the plant as it stands at the moment you use it, so the plant has to exist first.
Generate the layout
The equipment counts come from the placed plant — the inverters or string monitoring boxes, and the control rooms they feed — and the grouping is made when they are placed. With no layout there is nothing to count, and choosing Automatic only reports "Generate a layout first, then choose Automatic." See Your first layout.
No energy calculation is needed — running the yield calculation first adds nothing to the diagram.
Load the inverter file
The ratings and voltages come from the inverter file loaded on the inverter card. Without one the diagram is still drawn, by count: the transformers read rating needs OND, the low-voltage side LV needs OND, and the inverter's rating and the plant's MW AC figure are left off. See Inverter settings.
Open the SLD view and choose Automatic
Click the SLD tab (Ctrl+5). Nothing is drawn on entry: the view shows the diagram already stored, if there is one, and the Generate: row at the top of the tools panel offers Automatic and Manual. Choose Automatic. The chain is drawn on the sheet and the status line reads "Auto-built SLD (simple feeder) — edit as needed."
A diagram on the sheet is never redrawn on its own. After you generate the layout again, change a rule on the ACCB & Transformer card or load an inverter file, choose Automatic again so that the chain and the plant describe each other — and expect the sheet to be rebuilt, not merged with your edits.
The chain it draws
Which chain you get follows the inverter choice made at launch, because the two topologies convert the DC in different places. See Choosing a design mode.
PV → String Inverter (×N) → ACCB (×n) → Transformer (×n) → MV Panel → Grid| Stage | What it is | What the build writes |
|---|---|---|
| PV | The module field feeding the inverters | The module count and wattage, and PV Array with the string count |
| String Inverter (×N) | The string inverters placed across the plant. N is how many the layout placed | The rating in kVA from the inverter file, and String Inverter ×N |
| ACCB (×n) | The AC combiner boxes the inverters land on. n is the grouping's count: in each ICR block, the block's inverters ÷ Inverters per ACCB, max, rounded up | ACCB ×n |
| Transformer | The inverter duty transformers taking the collected output up to medium voltage | The rating, such as 16,000 kVA or a range 12,500–16,000 kVA, the voltages such as 33 kV/800 V, and Transformer ×n (k-Wdg) |
| MV Panel | The medium-voltage switchgear the transformers feed | 33 kV Switchgear — the card's MV voltage |
| Grid | The outgoing connection | GRID 33 kV |
The wires between the blocks carry the multiplicities: the modules and strings on one inverter, the most inverters on one ACCB, the most ACCBs on one transformer, and the transformer count.
The sheet is headed SINGLE-LINE DIAGRAM, with a line giving the plant's MWp DC, its MW AC (with an inverter file), the topology and the number of ICRs.
Both chains end the same way, and both are drawn along a horizontal bus — which is why the inverter and every transformer are placed already rotated to line up with it. See Building the single-line diagram.
Simple feeder or full SLD
The build has two forms, switched by the Full SLD (per-ICR / per-feeder) checkbox on the tools panel. It applies to the automatic build only.
| Full SLD | What is drawn | Paper |
|---|---|---|
| Off — the simple feeder | One annotated feeder, with each block carrying a ×N multiplicity for how many of it the plant holds | A3 |
| On | One row per feeder — per ACCB in a string-inverter design, per central inverter in a central-inverter design — across the whole plant, labelled ACCB-1, ACCB-2 … or C.Inv-1 … and grouped onto their transformers TX-1, TX-2 …, each marked with its own winding count. The rating and voltages are written under TX-1; the transformers feed the MV panel and the grid | A3 up to 10 feeders, A1 up to 28, A0 beyond |
Ticking or unticking the box while Automatic is chosen rebuilds the diagram in the other form, and the status line then reads "Auto-built SLD (full (per-ICR/feeder)) — edit as needed." for the full form. Choose the form before you start editing. The simple feeder is the readable one on a plant with dozens of machines; the full form shows every feeder and every transformer separately.
The transformer symbol
The transformer symbol is chosen from the feeders on the transformer, one low-voltage winding each:
| Feeders on the transformer | Symbol |
|---|---|
| 1 | 2-winding |
| 2 | 3-winding |
| 3 | 4-winding |
| 4 or more | 5-winding |
The simple feeder uses the most feeders on any one transformer; the full SLD uses each transformer's own. A transformer's winding count is its feeders plus one, so if your card allows more than four feeders per transformer, check the winding count written on the sheet against that and correct it with 📝 Text where it differs.
The grouping it draws
The counts, ratings and voltages on the chain are those of the plant's electrical grouping, set on the ACCB & Transformer card on the Electrical tab — Transformer in a central-inverter design:
| Rule on the card | Default |
|---|---|
| Inverters per ACCB, max | 15 |
| ACCBs per transformer, max (or central inverters per transformer) | 4 |
| Transformer size limit | 17.2 MVA, but never above the largest listed rating — 16,000 kVA with the default list |
| Standard transformer ratings (kVA) | 2500, 3150, 5000, 6300, 8000, 10000, 12500, 16000 |
| MV voltage | 33.0 kV |
The grouping is made per ICR block, and a block whose load exceeds the limit gets more transformers. Each transformer takes the smallest listed rating at or above its load. The full rules are on the card's own page.
The diagram, the bill of materials, the Summary view and the cable schedule all read the same grouping, so the box and transformer counts agree between them — there is no reconciliation to do.
If your scheme groups equipment differently — a different number of inverters per box, or transformer sizes you have already fixed with a supplier — set it on the card: the inverters per ACCB, the ACCBs per transformer, and your own list of ratings. Then choose Automatic again, and the diagram and the materials list follow your scheme.
What the annotations mean
Each block on the chain is annotated with two things:
- A multiplicity, written as
×N— how many of that item the plant carries. One inverter symbol carrying a multiplicity stands for every inverter in the plant, drawn once. That is normal single-line practice, and it is what keeps the sheet readable on a plant with dozens of machines. - A rating — for the transformers, from the grouping; for the inverter, the nominal AC power in the inverter file.
Both are put on the sheet by the build rather than typed by you. Where one is wrong — a rating that does not match the machine you are buying, or a count you have since revised — correct it on the sheet with the 📝 Text tool, or change the card and choose Automatic again.
What to do next
Treat the result as a first draft, in this order:
Check every rating
The ratings come from the grouping and the inverter file. Read each one against the equipment you are actually procuring, and correct the annotation where it differs.
Add what the build does not cover
The chain carries the generation-to-grid path. Isolators, breakers, instrument transformers, meters, relays, arresters and phase indication are all yours to place from the palette and wire in. See Symbol reference.
Complete the title block
The legend lists the chain's symbols and the notes carry four standard notes, but nothing identifies the project — no company name, no project name, no document number or revision. Write them in with 📝 Text.
Fit and export
Use ⤢ Fit to see the whole sheet, then export it from the tools panel, or leave it to be carried into the Detailed Project Report as the report's diagram page. See Exporting the diagram.
Where to go next
ACCB and transformers
The card whose rules set the combiner boxes, transformers and ratings on the chain
Symbol reference
The symbols to add on top of the automatically built chain
Building the single-line diagram
The sheet, the tools, and editing what the build placed
Exporting the diagram
The report page, a standalone PDF, and the CAD file
Symbol reference
Every symbol the SLD TOOLS palette carries, grouped by what it does — generation, AC distribution, transformers, protection and instrumentation.
Importing diagrams and custom symbols
Bringing an existing diagram in as a background to draw over, and tracing your own image into a vector symbol that exports to CAD as real geometry.