FiberCAD — Domain Knowledge Base

Source Videos
Network Architecture
Design Rules & Constraints
Equipment Specifications
Naming Conventions
Design Workflow (16 Steps)
CAD Best Practices
QC Checklist
Terminology Glossary

1. Source Videos

All domain knowledge in this document is extracted from the following five training recordings. Timestamp citations throughout use the format [Video Abbreviation, MM:SS].

Abbrev.	Full Title	Duration	Primary Topic	Key Sections
1x4/1x8	1x4 & 1x8 EXPLANATION.mp4	28m 25s	Splitter hierarchy, distributive split concept, address grouping logic	0:39 — distributive split intro; 1:08 — feeder cabinet; 1:58 — SPLT vs. splitter confusion; 8:50 — back feed rules
HLD-1	HLD RECORDING PART 1.mp4	66m 41s	High-level design workflow (steps 1–8), conduit routing, primary path	5:10 — step list; 49:56 — handhole sizing rules; 50:57 — 150 ft bend rule; 55:47 — 500 ft spacing rule
HLD-2	HLD RECORDING PART 2.mp4	64m 14s	High-level design (steps 9–16), secondary routing, cul-de-sac handling, dimensions, paper space	1:55 — secondary routing; 14:08 — cul-de-sac rule; 27:56 — conduit footage call-outs; 36:55 — road names; 39:44 — dimensions; 55:12 — title sheet
LLD	LLD RECORDING.mp4	54m 36s	Low-level design: fiber numbering, cable naming, splitter labels, ribbon assignment, splice documentation	1:22 — feeder count calculation; 8:40 — primary splitter labeling; 12:47 — fiber/tube color chart; 20:40 — secondary splitter labeling; 42:30 — three-way splice output ordering
CAD	CAD COMMAND FOCUSED TRAINING.mp4	72m 25s	AutoCAD setup, key commands, layer management, viewport placement, conduit/drop workflow	1:00 — freeze vs. off vs. viewport freeze; 2:44 — drag select modes; 4:20 — command aliases; 23:06 — no conduit coupling rule; 39:27 — SPLT handhole size clarification; 57:33 — splice types (pink vs. red)

2. Network Architecture

2.1 Distributive Split Model

The design methodology is called a distributive split — optical fiber is distributed from a central feeder cabinet and split progressively through two splitter tiers before reaching individual homes. 1x4/1x8, 0:39

Feeder Cabinet (Central Office)
  └─ 1–192 feeder fibers (or 1–132 for smaller cabinet) — one fiber per primary splitter
      └─ 1×8 Primary Splitter (in Medium handhole) — produces 8 secondaries
            └─ 1×4 Secondary Splitter (in SPLT handhole) — serves up to 4 homes
                  └─ Home Drop (flower pot → service drop)

2.2 Feeder Cabinet Capacity

192

Max feeder fibers — large cabinet

Each fiber feeds one 1×8. Max homes served: 192 × 32 = 6,144 units. 1x4/1x8, 1:08

132

Max feeder fibers — small cabinet

Placed when total polygon homes are under 132 groups. 1x4/1x8, 1:45

32 or 64

Homes per 1×8 group

One 1×8 handles 1–16 secondaries (up to 16×4 = 64 homes). Two 1×8s per MED handhole → max 64 homes. 1x4/1x8, 3:50

1:32

Total split ratio

1 feeder → 1×8 → 8 outputs → each feeds up to 4 homes via a 1×4. Net: 1 feeder serves up to 32 homes. 1x4/1x8, 1:25

2.3 Splitter Hierarchy — Port Math

Tier	Component	Input Ports	Output Ports	Homes Served	Max per Handhole
1st	1×8 Primary Splitter	1 feeder fiber	8	Up to 32 (w/ 1×4)	2 (requires MED)
2nd	1×4 Secondary Splitter	1 primary output	4	Up to 4	2 (in SPLT/SM)
—	Combined MED handhole	2 feeders	16 secondaries	Up to 64	—

Key insight: Address groups are counted in multiples of 4 (for a 1×4) and 8 (for a full 1×4 pair). Groups of 32 need one 1×8; groups up to 64 need two 1×8s — both in the same Medium handhole, saving one MED installation. 1x4/1x8, 3:50

2.4 Grouping Strategy

Boundaries are drawn to create logical groups that sum to 32 or 64 addresses, following the order of light (fiber path direction). Goals:

Prefer 60/64 groups over 64/64 to leave a spare port as an error buffer. 1x4/1x8, 5:17
If a group is exactly 32, place a single 1×8; prefer pairs of 32 (= 64) to share one MED handhole. 1x4/1x8, 20:24
Never strand a tiny group (e.g., 1 spare port requiring a full new primary) — consolidate into a nearby group instead. 1x4/1x8, 10:58
Groups must be geographically contiguous — no crossing all other homes to reach an isolated cluster. 1x4/1x8, 6:35
Large buildings (10+ units, large schools) get a dedicated feeder fiber reservation rather than a 1×8 group. 1x4/1x8, 11:54

2.5 Back Feeding

Sending a splitter's fiber backward along the cable path is permissible in limited circumstances. Acceptable: one handhole back-feed for a single outlying splitter. Unacceptable: extensive back-feed spanning many handholes. 1x4/1x8, 9:18

In LLD, back-feeding is allowed as long as sufficient fiber capacity exists on the cable. LLD, 40:40

2.6 Meet-Me Points & Project Chaining

FiberCAD projects are chained along a route ring. The entry point of a project (where fiber arrives from the previous project) is called the meet-me from (shown in white). The exit point to the next project is the meet-me to (shown in green). 1x4/1x8, 21:55

Projects receive fiber carrying specific fiber numbers from the previous project and must carry the correct count to the next project. Coordination of hand-off fiber numbers is a planning responsibility. 1x4/1x8, 23:15

3. Design Rules & Constraints

3.1 Conduit Spacing & Placement

Rule	Value	Notes	Source
Conduit offset from ROW	3 ft	All conduit placed 3 ft inside the right-of-way line. Parallel conduit uses same offset.	HLD-1, 20:18
48-strand cable offset from ROW	7 ft (or 10 ft from conduit)	Since conduit is 3 ft from ROW, the 48 cable is shown 10 ft from conduit centerline = 7 ft from ROW.	HLD-1, 40:44 CAD, 51:44
Soft max conduit run	500 ft	Standard max between handholes or flower pots. Do not exceed without justification.	HLD-1, 55:47
Hard max conduit run	650 ft	Absolute maximum. Use only when a property-line placement requires slightly more distance.	HLD-1, 1:06:53
Bend without handhole	150 ft rule	A bend (corner) may be made without placing a handhole if either the run before OR after the bend is ≤150 ft.	HLD-1, 50:57
No conduit coupling	Prohibited	Conduit cannot be split ("T'd") mid-run. All splits must occur at a handhole or flower pot. Each leg = a separate conduit.	CAD, 43:57
Cul-de-sac (cul-de-sac) routing	Never go fully around	Enter the cul-de-sac, place the handhole before the curve, cross perpendicular, and serve homes from a single cross. Never loop the full circle.	HLD-2, 14:08
Crossing — standard road	No handholes required	Handholes not required on both sides of a standard road crossing unless it is a DOT road, railroad, or environmental crossing.	HLD-1, 50:05
Crossing — DOT/railroad	Handholes both sides	A handhole must be placed on each side of any DOT road, railroad, or environmental crossing.	HLD-1, 50:19
Placement restriction	Property lines only	All handholes and flower pots must be placed on property lines (not mid-parcel or in driveways).	HLD-1, 26:23
Crossing angle	Perpendicular	All road crossings must be made at perpendicular (90°) to the road.	CAD, 43:27
Driveway avoidance	Required	Do not bore through driveways for drops or crossings. Choose property lines that avoid driveways.	HLD-1, 19:59

3.2 Splitter Placement Rules

Rule	Requirement	Source
1×8 and 1×4 in same handhole	Prohibited. Primary and secondary splitters must be in separate handholes.	1x4/1x8, 8:39
Max 1×8s per handhole	2 primaries per Medium handhole	1x4/1x8, 19:50
Max 1×4s per handhole	2 secondaries per SPLT handhole	CAD, 33:58
Centralization rule	Place handhole centrally in a group so fiber branches outward in both directions. Avoid placing at one end.	HLD-1, 52:53 CAD, 46:22
1×8 placement preference	Place 1×8s at three-way splices when possible to avoid creating extra handholes.	1x4/1x8, 9:28
Back-feed for single home	Acceptable to back-feed one fiber to a single outlying home or splitter.	1x4/1x8, 9:18

3.3 Handhole Sizing Rules

SPLT naming trap: The "SPLT" handhole is a size designation (13×17×24 inches), not an indicator that a splitter is present. It is the standard size for all 1×4 secondary splitter handholes. 1x4/1x8, 2:34

Condition	Handhole Type	Dimensions	Source
Contains a 1×8 primary splitter	MED (Medium)	24 × 36 in	HLD-1, 23:43
Three-way splice, no 1×8	SM (Small)	17 × 24 in (approx)	HLD-1, 23:51
Three-way splice with 1×8	MED	24 × 36 in — 1×8 requirement overrides	CAD, 39:14
Contains 1×4 only (standard)	SPLT	13 × 17 × 24 in	1x4/1x8, 2:52
Reserved future fiber	SM (Small)	17 × 24 in	HLD-1, 31:04
500-ft spacing handhole only (no splitter)	SPLT	Standard SPLT — smallest acceptable	HLD-1, 58:44
Has both 48-strand cable + 144-strand ring cable	SM minimum	SM required when two cable sizes coexist — a 144 does not fit a 13-in SPLT	CAD, 38:47
Size not used in this market	LH (Large)	30 in — never used in Hampton market	1x4/1x8, 2:52

3.4 Fiber & Cable Rules

Rule	Detail	Source
Numbering direction	Fiber numbers are assigned from the back (furthest home from cabinet = highest number). The last home gets fiber 1 or 2; the first home from the cabinet gets the highest assigned number.	1x4/1x8, 18:07
Use high numbers first	When distributing primary outputs to secondaries, always use the higher fiber numbers first (e.g., 15, 14, 13… not 1, 2, 3).	LLD, 1:19
Feeders and secondaries separation	Feeder fibers and secondary (P) fibers cannot share the same ribbon (12-fiber tube). If feeders use ribbon 1 (fibers 1–12), secondaries must start on ribbon 2 (fiber 13+).	LLD, 25:13
Ribbon color rule	If the last feeder fiber ends at an odd position, the first secondary starts on the next even position, and vice versa. XT (dead) fibers bridge the gap to complete the ribbon.	LLD, 37:29
Cable terminates at last handhole	The 48-strand main cable (orange) stops at the last handhole on a dead-end run. It does not continue to flower pots.	HLD-2, 29:32
Reserve fiber note	Areas with 10+ addresses in a dense cluster: place a handhole and add a note "Reserve feeder fiber for future use." Do not run individual 1×4s into such areas until directed by the client.	HLD-1, 15:14
Not-serviceable areas	Homes not accessible from the right-of-way cannot be served. Label as "not serviceable." Do not design conduit onto private property.	1x4/1x8, 25:26
Large building / school	Very large buildings with many units warrant a dedicated fiber reservation rather than integration into a 1×8 group. Judgment call by designer.	1x4/1x8, 12:03

3.5 Address / Boundary Rules

Threshold	Rule	Source
< 10 homes in cluster	Place handholes and 1×4 splitters normally. Run individual drops if accessible from ROW.	HLD-1, 15:14
≥ 10 homes in cluster	Reserve fiber only — do not design individual drops. Await client direction.	HLD-1, 15:35
5 homes in boundary	Needs two 1×4s (counted as "8" group). One 1×4 will have 3 empty ports — annotate with a star (★).	1x4/1x8, 4:14

4. Equipment Specifications

4.1 Handhole Sizes (Market: Hampton VA)

Code	Type	Approx. Size	Primary Use
SPLT	Standard (smallest used)	13 × 17 × 24 in	1×4 secondary splitters; 500-ft spacing hh; pass-through handholes with single cable
SM	Small	~17 × 24 in	Three-way splices (no 1×8); reserved fiber vaults; handholes serving two cable sizes
MED	Medium	24 × 36 in	Any handhole containing at least one 1×8 primary splitter
LH	Large	30 in	Not used in Hampton market

Sizing override rule: When two conditions apply, always use the larger handhole. Example: three-way splice (SM) + 1×8 (MED) → use MED. CAD, 39:14

4.2 Cable — 48-Strand Structure

Attribute	Value	Source
Total strand count	48 fibers	HLD-1, 17:43
Tube (ribbon) count	4 tubes (12 fibers each)	LLD, 21:18
Tube color order	Blue, Orange, Green, Brown (standard telecom color code)	LLD, 21:20
Fiber color within tube	1=Blue, 2=Orange, 3=Green, 4=Brown, 5=Slate, 6=White, 7=Red, 8=Black, 9=Yellow, 10=Violet, 11=Rose, 12=Aqua	LLD, 21:20
Feeder fiber 9 example	Fiber #9 = Yellow (9th position in the color sequence) — the 9th position in tube 1	LLD, 21:13
CAD representation	Orange polyline on its own layer; shown at 10 ft offset from conduit (7 ft from ROW)	HLD-2, 29:15

4.3 Splitter Specifications

Name	Alternate Name	Ratio	Outputs	Required Handhole
Primary Splitter	1×8	1:8	8 secondary fibers	MED (24×36)
Secondary Splitter	1×4	1:4	4 home drops	SPLT (13×17×24)

4.4 Conduit Placement Specs

Item	Specification	Source
Offset from ROW	3 ft — all conduit	HLD-1, 20:18
Parallel conduit	Yellow layer; placed at 3 ft offset; always separate from primary conduit; broken at every handhole and bend	HLD-1, 21:12
Main cable conduit (primary run)	Red layer; broken at every handhole, flower pot, and 90° bend	HLD-1, 27:41
Global width (polyline)	0.5	HLD-1, 5:20
Crossing method	Bored perpendicular — no open-cut shown in design	CAD, 43:27
Drop conduit	Yellow (parallel layer) — visually identical to parallel conduit; context determines use; no separate drop-conduit layer in this market	CAD, 49:23
Edge of pavement filet radius	15–25 ft typical; occasionally up to 35 ft for wider curves	HLD-1, 6:58 CAD, 26:08

4.5 Fiber Loop Sizes

Handhole Type	Loop Block Size	Placement
SPLT (13 in)	15	One side only
SM / MED (17 or 24 in)	50	Both sides (or all three at three-way splice)

CAD, 54:36

4.6 Splice Block Colors

Color	Meaning	When Used
Red	Three-way (or multi-way) fiber splice — fibers are physically cut and re-joined	At every three-way splice location; at each Medium handhole 1×8 entry point
Pink	Mid-sheath / pass-through splice — cable continues; mid-span entry only	At 1×8 primary handholes that are NOT on a three-way splice

CAD, 57:33 HLD-2, 22:04

5. Naming Conventions

5.1 Market / Polygon Codes

Element	Format	Example	Source
Market code	3-letter abbreviation	`HMP` (Hampton VA)	LLD, 1:38
Route / polygon ID	Market + polygon number	`HMP01`	HLD-2, 45:44
Drawing prop route name	`[MARKET]_FDH[##]`	`HMP_FDH01`	HLD-2, 45:44
Job number	Two-digit polygon + two-digit project	`0101` (polygon 1, project 1)	HLD-2, 46:03

5.2 Cable Names

Each cable segment that originates or branches at a splice gets a unique cable number within the project, assigned as the designer traces the route. LLD, 22:31

Part	Format	Example
Cable designation	`O[number]` (sequential)	`O1`, `O2`, `O3`
Rule: continuation vs. branch	At a three-way splice the cable continuing straight keeps a lower number; the perpendicular branch gets a new higher number.	Continuing = `O1`; branch = `O4`

5.3 Primary Splitter (1×8) Label Format

Field	Value / Format	Example
OLT (polygon loyalty number)	Single digit representing the polygon/OLT	`4`
Tier indicator	`P` = primary	`P`
Feeder fiber number	Integer (high numbers used first)	`15`
Market code	3-letter code	`HMP VA` (or shortened `HMP`)
Full format	`OLT[#] [P][feeder#] [MARKET]`	`OLT 4 P15 HMP VA`

LLD, 4:31

5.4 Secondary Splitter (1×4) Label Format

Field	Value / Format	Example
Splitter type	`1X4`	`1X4`
OLT loyalty number	Single digit	`4`
Parent feeder fiber	`[feeder#]P`	`9P` (fed by feeder 9)
Secondary number	`S[1–8]` (assigned back-to-front)	`S8`, `S7` … `S1`
Market code	`HMP VA`
Full format	`1X4 OLT[#] [feeder#]P S[#] [MARKET]`	`1X4 OLT4 9P S8 HMP VA`

LLD, 13:10

5.5 Fiber Call-Out Format (Cable Call-Out)

Each cable segment visible in a viewport requires a call-out. The call-out documents which fibers are active (carrying signal), which are feeders passing through, and which are spare.

Component	Label	Meaning
Dead / empty fiber	`XD`	Fiber position reserved but unused (often used to fill a tube before secondaries begin)
Active range	`[start]–[end]`	Consecutive fiber numbers carrying signal
Spare range	`HD [n] through [48]`	Fibers beyond used range — spare capacity
Separator	Semicolons between groups; commas within groups

Example cable call-out: XD, 1–8; OLT4 9P 1–8; HD 17–48 LLD, 21:37

5.6 Viewport Naming

Convention	Rule	Source
Viewport label format	`SP[n]` — sequential integers starting from 1	HLD-1, 8:24
SP1 = meet-me / start	First viewport always begins at the project's meet-me-from point (or cabinet for project 1)	HLD-1, 7:55
Order of numbering	Follow the order of light (direction fiber travels); number sequentially along the route	HLD-1, 8:30

5.7 Footage Call-Out Abbreviations

Abbreviation	Meaning	Example label
`H–H`	Handhole to Handhole	`H–H: 287 ft`
`H–F`	Handhole to Flower pot	`H–F: 43 ft`
`F–F`	Flower pot to Flower pot	`F–F: 67 ft`
`F–B`	Flower pot to Bend	`F–B: 15 ft`
`B–H`	Bend to Handhole	`B–H: 9 ft`
`H–B`	Handhole to Bend	`H–B: 15 ft`

HLD-1, 28:22 HLD-2, 35:41

5.8 Meet-Me Label Colors

Color	Label	Meaning
White	"meet me from"	Entry point — where fiber arrives from previous project
Green	"meet me to"	Exit point — where fiber is handed to next project

1x4/1x8, 21:55

5.9 Address Color Codes

Address Type	CAD Color	Notes
Standard serviceable addresses	Color 252 (dark gray in print)	Formerly color 8. Change from yellow layer to color 252 before publishing.
Yellow (working layer)	Yellow	Polygon outline / boundary — prints red; right-of-way shown pink for visual clarity during design only.

HLD-1, 3:37 HLD-2, 52:26

6. Design Workflow — High-Level Design (HLD)

The following 16-step sequence brings a project from "picked up from queue" to a permit-ready package. Steps are ordered as documented across HLD-1 and HLD-2. HLD-1, 2:00

Verify edge of pavement (EOP)

Confirm EOP polylines exist and are correct. If missing: use Spatial Manager satellite imagery + offset from center line, then filet at radius 15–25 ft. Match-prop from template block. HLD-1, 5:20
Set up viewports (paper space)

Critical to get right early — changing later causes cascading rework. Place SP1 at meet-me/start. Number sequentially following order of light. Adjust so no handhole or road is cut by a viewport boundary. Aim for natural break points. HLD-1, 7:10
Review 1×8 boundary groups

Planning team provides these on beginning projects. Designer verifies logic — groups summing to 32 or 64 along a logical path. If doing independently: count 1×4 boundaries, sum to 32 or 64. HLD-1, 12:20
Review / accept primary splitter placements

Planning team pre-places 1×8 splitters (Medium handholes) for initial projects. Verify they are centralized for each group. HLD-1, 13:00
Route primary conduit (main cable path)

Offset ROW by 3 ft; create conduit polyline; connect all Medium handholes. Place conduit on correct side of road (choose side with more homes for efficiency). Break at every bend and handhole. Maintain parallel conduit (yellow) where two conduits run side-by-side. HLD-1, 18:00
Place Medium handholes for 1×8 splitters

Position at property lines; avoid driveways; centralize relative to their boundary group. Three-way splice locations automatically qualify as MED if they also have a 1×8. HLD-1, 29:00
Draw 48-strand cable route (orange)

Offset ROW by 7 ft (= 10 ft from conduit). Break at every medium handhole. Cable ends at last handhole on dead-end; does not continue to flower pots. HLD-1, 40:30
Handle reserved-fiber areas

For clusters of ≥10 homes: place SM handhole, add "Reserve feeder fiber for future use" note. For inaccessible parcels: note "not serviceable." HLD-1, 30:47
Place secondary (1×4) handholes and route secondary conduit

Place SPLT handholes at property lines for all 1×4 secondary groups. Offset ROW 3 ft; route conduit to each SPLT. Centralize placement. Follow 500 ft max spacing. HLD-2, 1:55
Route drop conduit and place flower pots

For each home: run parallel conduit from SPLT; place flower pot at property line; cross perpendicular to home. No conduit coupling — each run is a separate conduit. Avoid driveways. HLD-2, 10:01
Place 1×4 splitter blocks in handholes

Insert 1×4 blocks into SPLT handholes. Max 2 per handhole. Add splice loops (15 for SPLT, 50 for SM/MED). Add red splice or pink mid-sheath block as appropriate. HLD-2, 23:47
Place "to CO" (central office) arrows

Add a "2-CO" arrow in every viewport pointing toward the feeder cabinet / meet-me. This indicates direction toward the central office. One arrow per viewport, near the entry point. HLD-2, 27:49
Run footage call-outs (conduit length labels)

Ensure all conduit is perfectly broken (at every HH, FP, and bend). Run list ACF1 on selected p_conduit layer objects. Run ACF2 (rotate), ACF3 (resize). Manually fix labels that are misplaced or have wrong abbreviations. Use H–H, H–F, F–B, B–H etc. HLD-2, 31:50
Add road names

Show Spatial Manager roads layer. Copy road-name block from template. Paste once per road per viewport, centered visually between ROW lines (do not use centerline — it is often off-center). All caps. Orient with T-orient command. HLD-2, 36:20
Run dimensions (ROW and conduit offset labels)

Use dim-align list: first "road setup" (enter layers e_row, e_curve, p_conduit), then "auto road dimension." Select centerline objects; pick left side then right side. Output: conduit-to-ROW and EOP-to-ROW callouts. Manually add where auto fails. HLD-2, 39:44
Finalize paper space — splice callouts, title sheet, publish

Fix viewport extents; run do-layout and relays lists; set viewport layer visibility (only 3 design layers + hatch on); add match-sheet callouts; fill drawing properties (route name, job number, date, first splitter address); run auto-rotate-180 on all text; publish PDF. HLD-2, 42:55

Step sequencing tip: Do all 1×8 primary handholes and conduit before touching secondaries. Do not break conduit segments precisely until just before running footage lists — breaking early wastes time if routes change. HLD-1, 51:10

7. CAD Best Practices

Extracted from the CAD command-focused training. These apply to AutoCAD (any recent version). CAD, 0:00

7.1 Layer Management

Technique	Command / Method	Notes
Freeze vs. Off	Freeze icon (snowflake) in Layer Manager	Both hide objects identically visually. Freeze additionally offloads layer to a separate memory store — marginally faster on large files. Prefer freeze. CAD, 1:08
Viewport Freeze	Second sun icon (with rectangle) in Layer panel while in paper space	Hides a layer only within the active viewport — still visible in model space and other viewports. Used for ~3 layers in standard HLD workflow. CAD, 1:52
Layer Isolate	`LAYISO` → first run `SE` → set lock/fade to 70–90	Dims all layers except the target. Allows match-prop across all objects on one layer quickly. Exit with `LAYUNISO`. CAD, 52:58
Current layer switch	Layer drop-down in Quick Access Toolbar (add via Home tab → right-click)	Put layer selector in QAT for fast switching without opening the full layer manager. CAD, 19:50
Draw Order	Select objects → type `DRAWORDER` → Front / Back	Use after placing handholes and flower pots — send them to front of conduit. Use at end of session via select-similar. CAD, 52:00

7.2 Key Commands and Shortcuts

Action	Recommended Alias	Default / Notes
Polyline	`P`	Default `PL`. Polyline is the primary drawing tool for all conduit and cable.
Copy	`C`	Default `CO`. Click base point, then click destinations; press Space to end.
Break at Point	`B`	Default `BR`. Use break-at-point (not plain break) — it splits a polyline without removing material.
Match Properties	`M` (or `MA`)	Copies all properties (layer, color, linetype, width) from source to targets. Essential for applying template layer properties.
Move	`M`	Standard. Choose base point, then destination.
Offset	`O`	Specify distance (e.g., `3`) then click direction. Use "through" mode for EOP freehand offsets.
Filet	`F`	Specify radius then click two lines. Filet with radius 0 joins two lines at their intersection.
Join	`J`	Combines multiple contiguous polylines into one. Objects must share endpoints (use snap).
Erase	`E`	Faster than Delete key for selecting and erasing in one step.
Extend	`EX`	Extends a polyline to the nearest intersecting object.
Trim	`TR`	Trims a polyline to the nearest intersecting object.
Select Similar	Right-click → Select Similar	Selects all objects of the same type AND layer. Critical command — use constantly.
Quick Save	`QS`	Saves without dialog. Use every 10–15 minutes; spam during intensive edits.
Regen	`RE`	Fixes display artifacts (linetypes not rendering, draw order issues). Run every 10–15 min.
T-orient	`TORIENT`	Rotates selected text/mtext to follow the orientation of two clicked points. Used for road names.
Text to Mtext	`TXT` → `TXT2MTXT`	Before first use: Settings → uncheck "combine into single object." Used to prepare footage labels for background masks.
Snaps toggle	`F3` or `Ctrl+F`	Turn off when freehand drawing; turn on when snapping to endpoints or intersections.
Ortho Mode	`F8`	Constrains movement/drawing to 90° angles. Useful for perpendicular crossings.
PickFirst setting	Type `PICKFIRST` → set to `1`	Enables selecting objects before issuing a command. If double-click stops working, PICKFIRST has reset to 0 — fix it.
Line space (align space)	`ALIGNSPACE`	Aligns a viewport in paper space: top-left of model area to top-left of sheet, bottom-left to bottom-left. Then lock viewport.

7.3 Selection Modes

Method	Behavior
Click	Selects single object clicked
Drag right (solid box)	Selects only objects entirely within the box
Drag left (dashed box)	Selects any object that the box touches — most useful for grabbing things in a crowded area
Shift+click	Deselects an individual object from current selection
Ctrl+C / Ctrl+Shift+C / Ctrl+V	Clipboard copy (unknown base point) / copy with chosen base point / paste with placement

CAD, 2:45

7.4 AutoRotate-180 Requirement

After all design work is complete, select all text objects (footage labels, splitter labels, addresses) and run the AutoRotate-180 LISP routine. This flips any text that is upside-down in the current viewport orientation to be right-side-up. This is always done at the end, before publishing. HLD-2, 57:32

7.5 Conduit Breakpoint Rules

Every conduit segment on the p_conduit (red) layer MUST be broken at:

Every handhole (MED, SM, SPLT)
Every flower pot
Every 90° bend
Every point where parallel conduit meets a different direction

Failure to break correctly will produce wrong footage call-out lengths when the ACF1 LISP routine is run. CAD, 40:30 HLD-1, 28:00

The 48-strand cable (orange layer) does NOT need to be broken at every point — it only needs to visually enter each handhole and look correct. Footage is calculated from conduit, not cable. CAD, 55:02

7.6 DXF Layer System

Layer Name	Color in Working File	Content
`p_conduit`	Red	Main cable conduit — broken at all equipment and bends
Parallel conduit	Yellow	Drop and parallel conduit; runs alongside p_conduit when two conduits share a trench
48-strand cable	Orange	Main fiber cable route (not footage-bearing)
e_row	Pink (visual only)	Right-of-way lines
e_curve	—	Edge of pavement (EOP) curved sections
Viewport	—	Paper-space viewport rectangles
Hatch	—	Polygon area hatches
defpoints	—	AutoCAD scratch/non-printing scratch layer
Addresses	Color 252 final	Address points; turned off during design, on during publishing

HLD-2, 43:30 CAD, 48:58

7.7 Useful LISP Routines

Command	Purpose	Notes
`ACF1`	Auto-generate all footage call-out labels from selected conduit on p_conduit layer	Must run after all conduit is perfectly broken. Takes significant time on large projects.
`ACF2`	Auto-rotate all footage labels	Run after ACF1.
`ACF3`	Auto-resize footage labels	Run after ACF2. Then manually reposition misaligned labels.
`do-layout`	Create paper-space sheet layout templates	Run once per project in paper space.
`relays`	Assign viewport numbers (SP1, SP2 …) to layouts	Enter `SP-` prefix; shift-click all viewports.
`AutoRotate180`	Flip all upside-down text to right-side-up	Run as final step before publish.
dim-align (`road setup` + `auto road`)	Auto-generate ROW and EOP dimension callouts	Run road-setup once per project; auto-road per viewport.
`t-length`	Helpful utility for calculating total conduit lengths	Load from list folder as needed.
`p-callout`	Port call-out helper	Load from list folder as needed.

HLD-2, 31:30

7.8 Snap Settings

Recommended snaps to keep always on: Endpoint, Insertion, Nearest. Enable as needed: Intersection, Perpendicular. Do not leave Perpendicular on permanently — it interferes with freehand drawing. Toggle snaps with F3. CAD, 8:48

8. QC Checklist

The following items are flagged across training videos as common QC issues or explicit checks performed before submission.

8.1 Design Logic

No 1×8 and 1×4 splitters in the same handhole. 1x4/1x8, 8:39
All 1×8 handholes are MED size (24×36). No primary in a SPLT or SM. HLD-1, 23:43
Each 1×8 boundary group sums to 32 or 64 (in multiples of 4 and 8). 1x4/1x8, 3:50
No group leaves a dangling single 1×8 output (e.g., 33 homes requires redesign, not "33 = 32 + 1 spare primary port"). 1x4/1x8, 10:58
All homes within each boundary are accessible from the right-of-way. Inaccessible homes are marked "not serviceable." 1x4/1x8, 25:26
Clusters of ≥10 homes are reserved (not individually designed). HLD-1, 15:35
No excessive back-feeding beyond 1 handhole. 1x4/1x8, 9:18

8.2 Conduit & Routing

All conduit offsets exactly 3 ft from ROW. HLD-1, 20:18
48 cable is 7 ft from ROW / 10 ft from conduit. HLD-1, 40:44
No conduit run exceeds 500 ft without justification; none exceeds 650 ft ever. HLD-1, 55:47
Bends without handholes: the shorter adjacent run must be ≤150 ft. HLD-1, 50:57
No conduit coupling mid-run — all splits occur at handholes or flower pots. CAD, 43:57
Cul-de-sacs: handhole placed before the curve; never loops fully around. HLD-2, 14:08
All crossings are perpendicular to the road. CAD, 43:27
No placement on driveways. HLD-1, 19:59
Parallel conduit is on the yellow (parallel) layer — not on p_conduit. HLD-1, 28:55

8.3 Conduit Break Points (critical for footage accuracy)

Every p_conduit segment is broken at each handhole. CAD, 40:30
Every p_conduit segment is broken at each flower pot. CAD, 40:30
Every p_conduit segment is broken at each 90° bend (not just visually curved). CAD, 40:30
Parallel conduit segments are broken at the same points as adjacent p_conduit. HLD-1, 28:47
No footage call-out spans a bend without being split into two separate callouts. HLD-2, 31:28

8.4 Paper Space / Viewports

No handhole or splitter is split across a viewport boundary. HLD-1, 11:35
SP1 is placed at the project meet-me / start point. HLD-1, 7:55
Viewport layer visibility: only 3 design layers + hatch layer are on. Dead-point and correct-port-addresses layers are off (do not print). HLD-2, 43:57
No overlapping elements — every overlap is a QC flag. HLD-2, 58:03
All text is right-side-up (AutoRotate-180 has been run). HLD-2, 57:32

8.5 Drawing Properties

Route name set to correct HMP_FDH## format. HLD-2, 45:44
Job number set (e.g., 0101). HLD-2, 46:03
Site address set to first splitter on project (or cabinet address for project 1). HLD-2, 48:52
Addresses changed to color 252 (not yellow, not color 8). HLD-2, 52:26
Parallels changed to red before publishing. HLD-2, 53:31

8.6 LLD Fiber Assignment

High feeder numbers used first (15 before 14 before 13…). LLD, 1:19
Feeders and secondaries never on the same ribbon (12-fiber tube). LLD, 25:13
XD (dead) fibers fill any gap between the last feeder and the start of secondaries in a tube. LLD, 21:39
Cable call-outs placed at every viewport the cable appears in. LLD, 26:10
Splice boxes show correct input and output designation. LLD, 38:49

9. Terminology Glossary

1×4 (Secondary Splitter)
Optical splitter that takes one fiber in and produces 4 outputs, each serving one home drop. Also called "secondary."

1×8 (Primary Splitter)
Optical splitter that takes one feeder fiber in and produces 8 outputs, each feeding a 1×4 secondary. Also called "primary."

48-strand cable
The main fiber distribution cable (48 fibers / 4 ribbons of 12). Shown in orange in CAD. Abbreviated "48."

ACF1 / ACF2 / ACF3
Custom AutoCAD LISP routines that auto-generate, rotate, and resize conduit footage call-out labels.

AutoRotate-180
End-of-project LISP routine that flips all upside-down text objects to right-side-up orientation.

Back feed
Routing a fiber in the direction opposite to the main cable flow to reach an outlying splitter or home. Acceptable in small doses only.

Bore
Horizontal directional drilling used to install conduit under a road without open-cut. All crossings are assumed bored.

Boundary (1×8 boundary)
A polygonal group of addresses assigned to be served by a single 1×8 splitter. Sums to 32 or 64 homes.

Cabinet / Feeder Cabinet
The central office termination point where the OLT and feeder fibers originate. Can hold up to 192 (large) or 132 (small) feeder fibers.

Conduit coupling
Splitting a conduit into two branches mid-run (T-connection). Prohibited in this market — all branching must occur at equipment.

Cot ring
The route ring/backbone path that connects polygon projects. Shows in CAD as a reference path indicating feeder direction and meet-me locations.

Cul-de-sac
A dead-end circular road. Rule: never loop the full circle — cross before the curve, serve homes from a single cross.

Defpoints
AutoCAD built-in non-printing scratch layer. Used for temporary scratch work polylines that must not appear in the final print.

Distributive split
The FTTH architecture used in this market: one feeder → 1×8 → 1×4 → home. Total split ratio 1:32.

EOP (Edge of Pavement)
The polyline marking the physical edge of the road surface. Drawn manually using satellite imagery + centerline offset + filet. On layer e_curve.

Feeder fiber
A single strand of fiber running from the cabinet to a primary 1×8 splitter. One feeder = one 1×8 = up to 32 homes.

Flower pot
A small access point in the conduit system at a home's property line, used to splice in the home drop. Placed on property lines.

FP (Flower Pot)
Abbreviation for flower pot (see above).

HH (Handhole)
An underground access vault (SPLT, SM, or MED size) containing splitters, splice closures, or pass-through hardware.

HLD (High-Level Design)
The permitting-level design phase. Produces the physical conduit/cable layout drawing package submitted for permits.

HMP
Three-letter market code for Hampton, Virginia.

LLD (Low-Level Design)
The construction/splicing-level design. Assigns specific fiber numbers, cable names, and splice documentation to the HLD drawing.

LISP routine
Custom AutoCAD script (coded in AutoLISP / Python) that automates repetitive tasks like footage labeling and text rotation.

Match prop (MA)
AutoCAD "Match Properties" command — copies all layer/color/linetype properties from one object to others. Essential tool.

MED (Medium handhole)
24×36-inch handhole — required wherever any 1×8 primary splitter is placed.

Meet-me
The handhole location where two adjacent polygon projects exchange fiber. Each project has a "meet-me from" (entry) and optionally a "meet-me to" (exit).

Mid-sheath splice (pink)
A splice closure at a 1×8 handhole that is NOT a three-way split — the cable continues without branching; only mid-span access is needed.

OLT (Optical Line Terminal)
The active network equipment at the feeder cabinet. Identified by a loyalty number (polygon identifier) in splitter labels.

Order of light
The direction fiber travels from the cabinet toward homes. Viewports are numbered, fiber assignments are made, and addresses are numbered in this order (or reverse for LLD numbering).

p_conduit layer
AutoCAD layer name for the primary (red) conduit. All footage calculations are based on polylines on this layer.

Parallel conduit
A second conduit run that shares a trench alongside the main p_conduit. Shown on the yellow layer. Used for drop conduit or diversity paths.

Primary splitter
See 1×8.

Ribbon
A 12-fiber tube within the 48-strand cable. Also called a "tube." Four ribbons per cable: blue, orange, green, brown.

ROW (Right of Way)
The public easement corridor alongside the road where conduit may be installed. All equipment must be within ROW; conduit offset 3 ft from the ROW line.

Secondary splitter
See 1×4.

Select Similar
AutoCAD command (right-click menu) that selects all objects sharing the same type AND layer as the currently selected object. Used constantly.

SM (Small handhole)
~17×24-inch handhole — used for three-way splices without a 1×8 and for reserved-fiber vaults.

SP[n] (Viewport label)
Paper-space sheet label. SP1 = first viewport (at project start/meet-me). SP2, SP3 … follow in order of light.

SPLT handhole
13×17×24-inch handhole — the smallest handhole used in this market. Despite the name, does not always contain a splitter; it is a size designation used for 1×4 locations and 500-ft spacing handholes.

Stub
A short conduit segment visually connecting the main conduit line to a handhole block in the CAD drawing.

Three-way splice
A splice point where the cable splits into two directions (plus the incoming direction = three total). Requires a red splice block and SM or MED handhole.

To-CO arrow
A directional arrow block placed once per viewport, pointing toward the feeder cabinet / central office. Labeled "2CO."

Viewport freeze
A layer freeze applied only to the active paper-space viewport. The layer still shows in model space and other viewports.

XD (cross / dead fiber)
Fiber positions declared empty/dead in a cable call-out, used to maintain ribbon-color alignment before active fiber assignments begin.

FiberCAD Domain Knowledge Base — Generated April 17, 2026
All rules and citations are extracted from the following training video transcripts. This document contains paraphrased content only; no verbatim reproduction.

Learning/transcripts/1x4_&_1x8_EXPLANATION.txt — 1×4 & 1×8 EXPLANATION.mp4 (28m 25s)
Learning/transcripts/HLD_RECORDING_PART_1.txt — HLD RECORDING PART 1.mp4 (66m 41s)
Learning/transcripts/HLD_RECORDING_PART_2.txt — HLD RECORDING PART 2.mp4 (64m 14s)
Learning/transcripts/LLD_RECORDING.txt — LLD RECORDING.mp4 (54m 36s)
Learning/transcripts/CAD_COMMAND_FOCUSED_TRAINING.txt — CAD COMMAND FOCUSED TRAINING.mp4 (72m 25s)

FiberCAD Domain Knowledge Base

Contents

1. Source Videos

2. Network Architecture

2.1 Distributive Split Model

2.2 Feeder Cabinet Capacity

2.3 Splitter Hierarchy — Port Math

2.4 Grouping Strategy

2.5 Back Feeding

2.6 Meet-Me Points & Project Chaining

3. Design Rules & Constraints

3.1 Conduit Spacing & Placement

3.2 Splitter Placement Rules

3.3 Handhole Sizing Rules

3.4 Fiber & Cable Rules

3.5 Address / Boundary Rules

4. Equipment Specifications

4.1 Handhole Sizes (Market: Hampton VA)

4.2 Cable — 48-Strand Structure

4.3 Splitter Specifications

4.4 Conduit Placement Specs

4.5 Fiber Loop Sizes

4.6 Splice Block Colors

5. Naming Conventions

5.1 Market / Polygon Codes

5.2 Cable Names

5.3 Primary Splitter (1×8) Label Format

5.4 Secondary Splitter (1×4) Label Format

5.5 Fiber Call-Out Format (Cable Call-Out)

5.6 Viewport Naming

5.7 Footage Call-Out Abbreviations

5.8 Meet-Me Label Colors

5.9 Address Color Codes

6. Design Workflow — High-Level Design (HLD)

7. CAD Best Practices

7.1 Layer Management

7.2 Key Commands and Shortcuts

7.3 Selection Modes

7.4 AutoRotate-180 Requirement

7.5 Conduit Breakpoint Rules

7.6 DXF Layer System

7.7 Useful LISP Routines

7.8 Snap Settings

8. QC Checklist

8.1 Design Logic

8.2 Conduit & Routing

8.3 Conduit Break Points (critical for footage accuracy)

8.4 Paper Space / Viewports

8.5 Drawing Properties

8.6 LLD Fiber Assignment

9. Terminology Glossary