3LD Tutorial

This tutorial introduces the three-line diagram (3LD) system and the manual drafting workflow from the August 11, 2026 training session. The final drafter guides were re-derived from the preferred transcript-corroborated full-recording run; timestamps below are absolute session time. Earlier screen-only evidence appears only where the preferred run has no competing record.

Evidence labels

The labels keep recording evidence separate from current repository behavior, guidance, and roadmap:

• Demonstrated — shown on screen in the training session.
• Repo-grounded — current, verifiable plugin behavior documented outside the recording.
• Recommended practice — stated guidance or preference, not demonstrated as a required procedure.
• Future — direction discussed in the session, not current procedure.

Understand the modular block library

Demonstrated · session 21:42

The template's model space contains a categorized library of modular 3LD blocks: Utility, Main Service Panel Details, Points of Interconnection (POIs), Subpanels, BOS Inline Equipment, Inverters, Microgrid Interconnection Devices (MIDs), and Batteries. Reference assemblies sit beside the parts.

The library is modular rather than a catalog of fixed drawings:

• Start with a base block, then apply overlays for active slots, main breakers, neutral lines, branch breakers, and other job-specific details. Demonstrated · session 22:13
• Reorder and stack equipment with MOVE and COPY, aligning splice lines and ground connections across adjacent blocks. Demonstrated · session 22:13
• Use the same spliceable MBE/MID/MSP pattern for demonstrated Tesla Gateway 3, Enphase System Controller 3, and BUI service stacks. Demonstrated · session 27:10
• Use POI reference points and grips to place line-side and load-side configurations. Demonstrated · session 33:43

Assemble a main service panel

Demonstrated · session 22:13–33:43

1. Start with MAIN_SERVICE_PANEL_TOP_BASE from PARTS OF MAIN SERVICE PANEL - TOP.
2. Apply the overlays required by the job, such as MAIN_SERVICE_PANEL_TOP_ACTIVE_SLOT, MAIN_SERVICE_PANEL_TOP_MAIN_BREAKER_VERTICAL, neutral lines, and branch breakers.
3. For a MID service stack, align the MBE, MID, and MSP blocks in their required vertical order.
4. Use MOVE and COPY to order the equipment and align splice lines and ground connections.
5. When copying a block, pick its shadow baseline as the base point and place it on the target's matching baseline.
6. Place the required line-side or load-side POI variant with its reference points and grips.

Recommended practice

• Omit or reorder job-dependent subcomponents and overlays only when the project rule permits it. The sum-of-all-handles rule was one demonstrated example, not a universal instruction. Demonstrated capability · session 22:13
• Edit block text by double-clicking it rather than exploding the block. Herbert described the redesigned attribute behavior as a goal for the new blocks, not a verified property of every block. Recommended · session 45:45

Draft a diagram manually

1. Open the current template

Repo-grounded · current plugin behavior, not from the recording

Run DT_NEW_FROM_TEMPLATE and open the newest standard-channel template. The command lists active DWG template versions from Design Tool's registry, downloads and SHA-verifies the selected template, and opens it as a new drawing. The registry—not this tutorial—is the authority for the current version. Because templates are served from that registry rather than copied machine-to-machine, template updates distribute block-library and diagram fixes.

2. Use the current command boundary

Repo-grounded · current plugin behavior, with earlier flow demonstrated at session 21:42–32:23

Use DT_TAGS3LD for wire-tag numbering in plugin v1.12.120 and later. Drafters no longer use APPLOAD or the old TAGS3LD helper for that job. Herbert's 3LD, BEND3LD, STACK3LD, and JUMP commands remain manual LISP helpers, not native DT_ plugin commands.

The clip below demonstrates the earlier APPLOAD + TAGS3LD flow. Keep it as historical evidence, not as the current instruction.

3. Draw the wires

These four commands are Herbert's manual LISP helpers, not native plugin commands. They place their output on the correct layers automatically. Demonstrated · session 30:08

3LD — straight three-wire run

Demonstrated · session 30:08

1. Type 3LD and press Enter.
2. Click the top-line point near the source device's wire number.
3. Click the matching destination point.
4. Press Enter to draw all three wires.

BEND3LD — three-wire run with a bend

Demonstrated · session 31:29

1. Type BEND3LD and press Enter.
2. Click the source point.
3. Click the destination point. The routed bend draws automatically.

STACK3LD — several runs in one pass

Demonstrated · session 31:45

1. Type STACK3LD and press Enter.
2. Click the source and destination for the first pair.
3. Repeat for each additional pair.
4. Press Enter once after the last pair. All queued runs draw together.

JUMP — wire crossover

Demonstrated · session 32:23

1. Type JUMP and press Enter.
2. At Select wire to jump:, choose the wire that should pass over the other.
3. Click the crossing point to place the jump arc.

4. Mark existing equipment and number tags

Repo-grounded current command; earlier flow demonstrated at session 21:42 and 27:10

Use (E) on existing-equipment wire tags and add one diagram note explaining that (E) means existing. Run DT_TAGS3LD and verify that ordinary tags renumber from left to right while existing markers are preserved. Re-run it after adding or copying equipment. The clip above demonstrates that behavior with the earlier TAGS3LD helper.

5. Choose the sheet presentation

Demonstrated · session 30:08

Open the paper-space layout containing the diagram viewport. Freeze the single-line-only layer in that viewport—the session used RED - 1LD ONLY—to switch the viewport between single-line and three-line presentation. The first wire-command clip above shows this workflow.

6. Tidy callout leaders

Demonstrated · session 33:43

If multileader text lands at the default angle and overlaps nearby content, select it and drag its text-landing grip clear. Fuller leader automation was discussed as direction rather than delivered procedure. Direction only

Feedback and open routing questions

The Learning Lab is a future reviewer/admin workflow and is not part of the drafter SOP.

Channels that exist today

• Report a plugin bug or screenshot-ready problem with DT_REPORT_ISSUE in AutoCAD (JobEngine ribbon → Assist). Repo-grounded · current plugin behavior, not from the recording
• The existing CAD chat handles general CAD questions. The session referenced it but did not settle whether 3LD/ELD traffic belongs there. Future/open question · session 42:32
• Include the Design Tool session link and a screenshot when they add context, especially for a plugin bug. Supplementary team practice outside the recording

Proposed, not yet established

Do not route work to these destinations until the team confirms they exist:

• A separate ELD channel was discussed, but no channel was named or shown. Future/open question · session 42:32
• A dedicated ELD feedback button was another option under evaluation. Future · session 42:32
• A breakout call for the battery-catalog problem was proposed, not established as an operating pattern. Recommended · session 00:43, supplementary screen-only record
• Posting follow-up questions after the session was requested in the context of a rollout that had not happened. Future · session 48:09

What's coming

These items were discussed as direction, not current procedure:

• Enable the authored Automatic Transfer Switch blocks. Future · session 08:45 record; Q&A at 10:31
• Automate leader placement beyond the demonstrated manual grip adjustment. Direction only · manual fix demonstrated at session 33:43
• Notify the team after the remaining rollout integrations are complete. Future · session 48:09
• Reduce SLD/electrical QC corrections through automation. This was a goal, not a measured result. Recommended · session 45:45

Canonical sources: SOP — drafting a 3LD with the AutoCAD toolchain, Intro — the 3LD system for new drafters, and 3LD comms & feedback. Those guides are the text authority for this projection. The session playbook.html remains an evidence artifact, not an independent prose source.