Using the Parts Library
The parts library turns a generic connector box on your schematic into a real, orderable part: a housing part number plus the crimp contacts, wedgelock, seals, and cavity plugs that go with it. Once a part is assigned, the BOM counts every one of those pieces for you.
Open the library
Section titled “Open the library”Click the Library tab in the right sidebar (next to Inspector and Issues). The panel is headed Parts library and lists every manufacturer as a collapsible group, with each manufacturer’s product series nested inside.
You can also right-click any connector on the canvas and choose Assign part… — that selects the connector and jumps straight to the Library tab.
What’s in the built-in catalog
Section titled “What’s in the built-in catalog”The built-in catalog ships with the app and covers a broad spread of connector families, including:
| Domain | Families |
|---|---|
| Automotive / motorsport | Deutsch DT, DTM, DTP, HD30, DRC, Autosport; Amphenol AT/ATM; Aptiv Weather-Pack, Metri-Pack 150/280, GT 150/280, Sicma; TE SUPERSEAL, AMPSEAL, MQS, Junior Power Timer, MATE-N-LOK; Molex MX150, CMC; Sumitomo; Yazaki; Bosch Compact; Kostal; injector connectors; OBD; FAKRA |
| Mil / aero | MIL-DTL-38999, MIL-DTL-5015, Souriau 8STA (Autosport), LEMO |
| Board-level | JST (EH, GH, NH, PH, SH, SM, VH, XH, ZH), Molex Mini-Fit Jr., Micro-Fit 3.0, KK, PicoBlade, Hirose DF13, Dupont headers, IDC ribbon, FFC/FPC, debug headers |
| Industrial | M8/M12 circular, Harting Han, DIN 43650, terminal blocks, fieldbus, IEC 60309 |
| Data / consumer / power | D-Sub, HDMI, DisplayPort, DVI, USB, SATA, modular RJ, audio, RF coax, DC barrel, IEC 60320, NEMA, EV HV, MC4 solar, RC battery, trailer, crimp terminals |
Each part row shows the part number, cavity count, an M/F tag, and — when the data exists — a current-rating tag and an IP-rating tag. Hover a row for the full description: contacts, wedgelock, suppliers, and notes. The ↗ link next to a row opens an Octopart search for that part number, so pricing and stock are always live.
Find a part
Section titled “Find a part”Type in the Filter — pn, series… box at the top of the panel. It matches against part number, series, and description, and hides manufacturers with no hits. While a filter is active, matching series groups expand automatically.
Place or assign a part
Section titled “Place or assign a part”The library is one-click, and what the click does depends on your selection:
- Nothing selected — clicking a part drops a new connector node on the canvas, named
CONN1,CONN2, … with the cavity count and cavity labels stamped from the part. - A connector selected — clicking a part assigns it to that connector, resizing the cavity list to the part’s count and applying its cavity labels. Use this to “re-part” a generic connector you sketched earlier.
The panel’s hint line always tells you which mode you’re in.
You can also pick a library part while creating a connector: press C (default binding, changeable in settings) or right-click the canvas to open the New connector dialog, then choose from the Library part dropdown instead of None — ad-hoc connector. The part fixes the cavity count, labels, and gender; the stepper is disabled. See hotkeys for the full list of bindings.
Refine the accessory picks
Section titled “Refine the accessory picks”Assigning a part gives you sensible defaults: the first compatible contact, the wedgelock, and the first listed backshell, seal, and cavity plug. Select the connector and open the Inspector tab to see the Part section, which shows the housing, series, sealing, wire range, and suppliers, plus dropdowns for Contact, Wedgelock, Backshell, Seal, and Cavity plug. Set any of them to none to drop that piece from the BOM, or use Detach part to make the connector generic again.
Mixed-size housings (for example Deutsch HD30 layouts that combine size-16 and size-20 contacts) carry per-cavity default contacts, and you can override the contact on individual cavities in the Inspector.
Contact and housing current ratings from the library feed the ampacity check — the effective per-cavity limit is the minimum of the housing rating, the chosen contact’s rating, and the wire’s ampacity — so an overloaded circuit shows up in the Issues tab.
How parts explode into the BOM
Section titled “How parts explode into the BOM”The BOM does not just list housings. For every connector with an assigned part it counts:
| BOM line | Counted as |
|---|---|
| Housing | One per placed connector, grouped by part number |
| Wedgelock, backshell, seal | One each per connector, from the Inspector picks |
| Contacts | One per crimp — only cavities that actually carry a wire, counted per actual contact part number (a per-cavity override beats the default) |
| Cavity plugs | One per empty cavity, only when the part has a Cavity plug pick (sealed housings) |
So a 12-way sealed connector with 8 wires lands as 1 housing + 1 wedgelock + 8 contacts + 4 cavity plugs. See Exporting for getting the BOM out.
Generic vs. library parts
Section titled “Generic vs. library parts”You don’t have to use the library. An ad-hoc connector (created without a part) is just a label and a cavity count — perfect for early sketching. On the BOM it appears as a single placeholder line like CONN3 (4 cav), with no contacts or accessories. Assign a real part later, whenever you settle on hardware; wiring is preserved.
Assigning a part copies it into your design file. Documents stay self-contained: a collaborator can open your file with a different (or missing) library and nothing dangles. See Collaboration for how that plays with git.
Load a manufacturer file for this session
Section titled “Load a manufacturer file for this session”Click Load manufacturer JSON… at the bottom of the panel to add your own manufacturer file to the catalog. A successful load confirms the manufacturer name and connector count; a bad file is rejected with a list of every problem found, so you can fix the file in one pass rather than error by error.
Files loaded this way last only for the current session — after restarting LoomFlow, load them again. Parts you already assigned are unaffected, because assigning copies the part into your design file. Files sharing a manufacturer name merge into one catalog, so a loaded file can extend a built-in manufacturer — and if it redefines a part number that already exists, the loaded definition wins, which lets you patch a built-in entry without touching anything else.
To write your own files — by hand, or letting an LLM do the datasheet drudgery — see Library authoring and the library format reference.