Electrical drawing approval that checks every breaker, cable and CT against the consultant's own load schedule and your standards, with clause-cited comments on day one
Clause-cited comments on day one, not after resubmission.
See one case, screen by screen ↓Before a new building is connected, its consulting engineer submits the electrical design for approval: single line diagrams, the schedule of loads, the MDB schedule, the substation room layout and the earthing layout. A design approval engineer checks every breaker, cable, CT, relay setting and room dimension against the utility's design standards and circulars, then writes the comment sheet. The same few clauses return most designs, but each one is checked by hand, afresh, on every package.
The drawing and the load schedule are separate documents. So the commonest mistake, a breaker or cable smaller than the load the consultant's own schedule declares, is easy to miss: the incomer sized to an old load, the CT ratio sized to the breaker, the cable sized without derating. It surfaces at the second or third resubmission, each one restarting the review clock, or at site inspection, where an undersized breaker or cable means nuisance trips, an overheated cable or a failed inspection that holds up energisation.
Estimated split of the 19 working days from first submission to approval in Lumina's review log (the sample utility's baseline), in working days, by hand and with the solution.
Six agents read the drawings and the load schedule together and cite every clause; a design approval engineer signs.
Halvorsen & Ade Consulting Engineers submit the design for Cedar Quay Residences, Tower B: 14 storeys, 126 apartments, 6 retail units and 8 EV bays, on a new 1000 kVA substation, SS-7114, on 11 kV feeder F-38. The load band is 250 kVA–1 MVA, so Lumina's review clock is 3 working days, due Thu 15 Oct. Here is what happens, screen by screen, in the working solution.
Priya's Submissions list shows 23 open packages, 4 due today and 6 resubmissions; the median to first comments over the last 30 days is 1 day. Each row has its load, its revisions, its clock and what the agents found: Harbourgate Hotel passes every check and Orchard Row Townhouses has only 2 advisory comments, so both are ready to approve; Fenwick Lane Retail Park is on day 3 of 3 with 2 must-fix comments.
“Review clock: 1 / 3 / 5 working days by load band · it restarts at each revision”
EDA-26-0418 Rev A arrives through the portal: E-001 single line diagram, E-002 MDB schedule, E-101 substation room, E-201 earthing, E-301 riser, the LS-02 schedule of loads and a 38-page calculation pack. The drawing reader reads 270 devices, cables and dimensions on five drawings; the load schedule checker reads 42 rows and seven boards. Nothing is unreadable, so nothing is guessed.
“Six agents checked this package when it arrived at 08:52 — 4 min 12 s. Every step is on the record.”
The single line diagram opens as a CAD sheet with the comments on the drawing itself. Bubble 1 sits on main incomer Q1: a 400 A MCCB for a 520 A design current. The rail shows what the drawing says, what the load schedule says, the clause quoted word for word and the comment the consultant will read. Ten passed checks show as green ticks on the devices they cover.
“Rated 400 A for a 520 A load · LDS-201 §5.3.2 · Must fix”
The load check recomputes LS-02 with Lumina's diversity table: 1,294.6 kVA connected, less 934.2 kVA of diversity, gives a maximum demand of 360.4 kVA, a 520 A design current at 400 V. The consultant's own diversity factors and total match the recompute. E-001 shows Q1 at 400 A, 120 A short.
“The consultant's total, 360.4 kVA, matches the recompute. The schedule is right; the drawing is not.”
Priya switches the incomer to a 630 A ACB, the incoming cable to 2 × 4C 240 mm² (704 A after derating) and the metering CT to 800/5. Every dependent rule re-runs: Ib 520 A ≤ In 630 A ≤ Iz 704 A, and 800/5 clears the 650 A CT minimum. Comment 4 stays open, because the retail feeder and its board incomer are both 250 A.
“C1, C2 and C3 would close · This is the fix in the comment sheet. C4 is on the retail board.”
On E-201, note 6 records a measured earth electrode resistance of 2.4 Ω; LDS-305 §4.1 allows 1.0 Ω for an 11/0.4 kV substation, so the comment asks for an extended ring or more rods, a fall-of-potential re-test and the test sheet. On E-101 the substation door gives 1.2 m clear where a 1000 kVA transformer needs 1.5 m × 2.4 m, an advisory that goes to substation planning.
“Earth 2.4 Ω, limit 1.0 Ω · LDS-305 §4.1 · Must fix”
The compliance checklist lists the 31 checks in force for the 250 kVA–1 MVA band, by section: incomer and protection, cables, metering, earthing, substation room, loads and power quality. 24 pass; 5 are must fix and 2 advisory. Each line shows its clause and links to its comment on the drawing.
“31 checks in force for the 250 kVA–1 MVA band · each tied to its clause and its place on the drawing”
Priya accepts the seven comments; she could edit the wording or dismiss a comment with a reason that goes on the record. She signs the return with the meaning of her signature and her PIN. No agent can send the sheet.
Meaning of signature: “I have reviewed this design against the standards in force”
Tomás gets one comment sheet from Lumina Network Connections: each comment with its drawing location, the value found, the clause and what is required — a 630 A ACB with LSIG trip, 2 × 4C 240 mm² in parallel, CT 800/5 class 0.5S, a 125 A retail board incomer or a selectivity table, and an earth re-test at 1.0 Ω or less. Rev B will restart the 3-day clock, and the agents will re-check only what changed.
“Sent to Tomás Okafor — every comment with its clause, on day 1”
Tower B's 360.4 kVA appears on SS-7114 as in review: 36% of the 1000 kVA transformer, with Tower C's 410 kVA reserve request adding 41% more. Feeder F-38 from Saltmarsh primary has a firm capacity of 7.2 MVA: 4.9 MVA July peak, 0.9 MVA approved but not yet connected, 0.36 MVA pending, leaving 1.04 MVA. The load stays pending until the design is approved.
“After Tower B, F-38 keeps 1.04 MVA of firm headroom. Tower C's 410 kVA enquiry fits, leaving 0.63 MVA.”
The same design package, seen by the four people who own it — what their week looked like, and what it looks like now.
Six agents read the drawings and the load schedule together and cite every clause; a design approval engineer signs.
Reads single line diagrams, layouts and riser diagrams in PDF or DWG: every breaker, cable, CT, relay setting, busbar and dimension, with its place on the sheet. On a resubmission it compares Rev B with Rev A and finds what changed.
Reads the schedule of loads and recomputes maximum demand board by board with Lumina's diversity table (LDS-201 Table 4-1) and the circulars in force, such as EV chargers at 1.00.
Matches every device and cable on the drawing to the load it carries: Ib ≤ In ≤ Iz with the corrected cable rating, CT primary at least 1.25 × Ib, selectivity of at least 1.6 between series devices, and breaking capacity against the fault level.
Runs every check in force for the load band and cites the clause and its revision for each result, from LDS-201, LDS-305, LMS-110, LSR-02 and the circulars.
Drafts the comment sheet: one comment per finding, with its location, the value found, the limit, the clause and the action. On a resubmission it closes each earlier comment with the evidence or keeps it open.
Adds each declared load to the substation and 11 kV feeder plan as pending, and commits it when the approval is signed.
Accepts, edits or dismisses, then signs. The agents propose; a named person decides.
Ask about a device, a clause or a submission in plain words. Every answer cites the sheet, the schedule row and the clause.
Why is the main breaker a must fix?
E-001 shows Q1 as a 400 A MCCB. The consultant's own schedule totals 360.4 kVA, a 520 A design current at 400 V. LDS-201 rev 7 §5.3.2 needs the incomer at or above the design current and at or below the cable rating, so the comment asks for a 630 A ACB, and C2 asks for a cable that can carry it.
Which submissions could miss their clock today?
Four are due today: EDA-26-0402 Saltmarsh Medical Centre (Rev C, 1 must fix), EDA-26-0405 Fenwick Lane Retail Park (Rev B, 2 must fix), and two ready to approve with no must-fix comment — EDA-26-0409 Orchard Row (2 advisory) and EDA-26-0411 Harbourgate Hotel.
Does Circular 2026/07 change the Tower B load?
No. Circular 2026/07 counts EV chargers at a diversity of 1.00 unless a load-management system limits them. LS-02 already counts the 8 chargers at 7.4 kVA and 1.00 — 59.2 kVA — so that check passes. It superseded Circular 2024/03 (0.40), which is never cited.
Is there headroom on F-38 for Tower B?
Yes. F-38 has a firm capacity of 7.2 MVA: 4.9 MVA July peak, 0.9 MVA approved but not yet connected, and Tower B's 0.36 MVA pending — leaving 1.04 MVA. SS-7114 runs at 36% with Tower B and 77% if Tower C's 410 kVA reservation is added.
13 screens from the working solution, on its sample data. Pick one to see it large.
The review clocks, the standards in force, the diversity table, severity and sign-off are settings, chosen by the utility and saved as a new version.
| Setting | Default | Choose from |
|---|---|---|
| Review clocks by load band | 1 · 3 · 5 working days | Up to 250 kVA · 250 kVA – 1 MVA · over 1 MVA or 11 kV supply, each in working days; the clock restarts at each revision and pauses while the package is with the consultant |
| Standards in force | LDS-201 rev 7, LDS-305 rev 4, LMS-110 rev 3, LSR-02 rev 5 | Plus Circulars 2026/07 and 2026/04 · superseded versions kept, never cited |
| Diversity table (LDS-201 Table 4-1) | Apartments over 100 units 0.16 | Retail units 0.70 · EV chargers, no load management 1.00 · pumps and ventilation 0.60 · lifts 0.50 · common lighting and power 0.50 |
| Severity | Ratings below the load: must fix | Must fix · Advisory — earth resistance over limit is must fix; power factor below 0.95 and substation room access are advisory |
| Return or approve | Design approval engineer | Priya, Samir, Ana |
| Loads over 1 MVA, and waiving a must-fix comment | Second signature | Grace Lindqvist — a waiver also needs a reason |
| Substation size and room | Confirmed by substation planning | Daniel Mwangi |
| Comment wording | On | Write for the consultant (value found, limit, clause, action) · cite the revision of the standard · never size the equipment — each On or Off |
Every figure is labelled: a target the solution is built to, an estimate, a typical published result, or a proven one.
“demo” = seen in the working solution, on its sample data · “target” = the design goal, measured in the live solution · “estimated” = the baseline we set for Lumina, the sample utility (2.7 submissions per approval, 19 working days from first submission to approval), and our split of those days · “typical” = published figures (NREL, 2023: automated plan review left residential solar projects 29 % less likely to fail inspection). Context: published LV design approval clocks of 1–3 working days by load band (a Gulf utility's connection page); the Great Britain connections standard for LV/HV design approval, 90 % within 10 working days (Ofgem SLC15); the rule Ib ≤ In ≤ Iz (IEC 60364-4-43 §433.1, BS 7671 §433.1.1). Lumina Utilities, its standards (LDS-201, LDS-305, LMS-110, LSR-02), every consultant, development, substation and feeder, and every person named on this page are fictional — characters and sample data in the working solution.
Software for the utility engineers who approve a consultant's electrical design before a building is connected. Electrical Drawing Approval reads the single line diagram, layouts and load schedule the moment they arrive, checks them against your design standards and circulars, and drafts a clause-cited comment sheet. A design approval engineer decides each comment and signs.
The load schedule checker recomputes maximum demand from the schedule with your diversity table, and the rating matcher checks each breaker, cable and CT against the load it carries: Ib ≤ In ≤ Iz with the derated cable, the CT ratio and selectivity. In the sample package that is how a 400 A incomer on a 520 A load was caught on the first round.
Yes. It checks against the standards and circulars you set as in force for each load band, and every comment cites the clause and its revision. Superseded circulars are kept for reference and never cited.
When a revision arrives, the drawing reader compares it with the previous one and only the checks the changes touch are re-run. In the sample, Rev B of Larchmont Business Park closed 5 of 6 earlier comments and kept one open: the chiller feeder cable, 287 A after derating on a 315 A breaker.
No. It states what the clause requires and the value found, and never changes the consultant's numbers or picks a product. The design stays the consultant's; the decision stays with your engineer.
Yes. Agents read, check, cite and draft, and never sign or commit capacity. Only a design approval engineer signs a Return or an Approve, loads over 1 MVA and any waived must-fix comment need a second signature, and a dismissed comment needs a reason on the record.
Yes. The review clock for each load band, the standards in force, the diversity table, which findings are must fix or advisory, who signs and the comment wording are all settings, saved as a new version that applies to new submissions.
The Agentic Solution Engine builds and deploys it from your requirements and documents — your design standards and circulars, your diversity table, comment sheet template and a sample of past submissions — and it goes live once every quality gate has passed. We will walk you through it on your own design packages first.
Complete or deficient in minutes, not days.
1-min demoUtility NOC Application ProcessingEvery NOC checked against every asset buffer, issued inside 2 working days.
1-min demoNew Service Connection ProcessingFrom application to energised, every step tracked.
1-min demoWe'll run Electrical Drawing Approval on a sample of your own past submissions and comment sheets.