Free · Tool
Connection Assistant for AutoCAD Plant 3D
A catalog is only as good as the connections Plant 3D knows for it. The assistant explains the two configuration files, reads yours, compares them with the end types of your catalog and adds missing end codes and pipe connections.
How to proceed
- Back upCopy both files
- LoadFiles + catalog into the assistant
- CompleteCheck type and counterpart per end type
- ReplaceClose Plant 3D, swap files, test
Instructions and a list of changes are included in the download. Help with setup: Support or Spec creation.
Why end codes? – So that Plant 3D connects correctly
Every connection of a catalog part has an end type (end code) – e.g. BV for butt weld end, FL for flange, SW for socket weld, THDF/THDM for female/male thread, PL for plain pipe end. The end code tells Plant 3D how this connection is joined to the next part. When routing, Plant 3D compares the two connections at each point: nominal size, end type and – for flanges – pressure rating and facing. If a connection rule matches, Plant 3D automatically inserts the correct connecting parts: gasket and bolt set between two flanges, a weld between two weld ends, gasket and clamp for a clamp connection.
With correct end codes
- Parts snap together correctly during routing – flange to flange, weld end to weld end.
- Gaskets, bolt sets and clamps are added automatically to the model, bill of materials and isometric.
- The isometric shows welds and connections with the correct symbol.
- Validation reliably finds open ends and mismatched connections.
With missing or incorrect end codes
- Unknown end code (not in EndCodesConfig.xml): Plant 3D cannot classify the connection.
- No rule in DefaultConnectorsConfig.xml: parts don't connect, gasket and bolts are missing from the bill of materials and iso.
- The same end code for two connection types: Plant 3D connects parts that don't fit together – e.g. a clamp to a dairy pipe thread.
- Errors often only show up in the isometric or when ordering.
In short: the catalog defines the end code per connection, EndCodesConfig.xml makes it known to Plant 3D, DefaultConnectorsConfig.xml says what goes in between for this end code. Only when all three match does Plant 3D work correctly during routing, in the bill of materials and in the isometric – exactly what the assistant checks and completes.
The two files of the connection configuration
Version number and language folder (R26.0, deu) depend on your Plant 3D version. Simply type %APPDATA% into the Explorer address bar.
EndCodesConfig.xml – which end types exist
List of all end types (end codes) with description and properties: trimmable (pipe end), flange-like, wafer. Every end type a catalog uses at its connections must be listed here – otherwise Plant 3D does not know it.
Likely location (per user and computer):%APPDATA%\Autodesk\Autodesk AutoCAD Plant 3D 2027\R26.0\deu\Support\EndCodesConfig.xmlor in your company's shared support folder (Options › Files › Support File Search Path). With several workstations, update it on each one.
DefaultConnectorsConfig.xml – what connects to what
Pipe connections of the project: end type 1 to end type 2, condition (nominal size, pressure rating, facing) and the connecting parts Plant 3D inserts – gasket and bolt set, weld, clamp, thread. Without a matching rule, Plant 3D does not join the parts.
Likely location (per project):<project folder>\DefaultConnectorsConfig.xmlnext to Project.xml. Template for new projects:%APPDATA%\Autodesk\Autodesk AutoCAD Plant 3D 2027\R26.0\deu\DefaultProject\DefaultConnectorsConfig.xmlor in the folder of your project template.
How catalog and configuration fit together
- CatalogConnection with end type, e.g. CRF (compression ring)
- EndCodesConfig.xmlknows the end type CRF
- DefaultConnectorsConfig.xmlRule "CRF to PL" with connecting part
- Plant 3Djoins the fitting and the pipe
After the check, the Catalog Checker reports if a catalog has additional end codes and passes them directly to the assistant.
Typical cases
Basic rule: each connection type gets its own end types – then it remains unambiguous which parts Plant 3D joins.
Flanges type C/D, E/F
Tongue/groove and male/female faces only fit in pairs – use dedicated end codes (e.g. FLC/FLD) with their own flange connection, not "FL".
Compression and clamping rings
Fitting body with its own end type on a plain pipe (PL), condition: pipe outside diameter.
Union nut and slotted nut
Threaded nozzle and cone/collar nozzle as a pair, gasket and nut as connecting parts (e.g. DIN 11851, DIN 11864-1).
Clamp and aseptic
Clamp nozzles with gasket and clamp; block flange and Varivent connections with their own end types.
Press fittings
Press connection on the pipe – use the standard end type "P" or create your own rule for MJF/MJM.
Customer configurations
Identical end types for different connection types lead to incorrect connections – the assistant shows overlaps.
Basis & sources
What the tool calculates with, which standards and data it relies on and where its limits are. As of September 2026.
Calculation method
- LoadEndCodesConfig.xml, DefaultConnectorsConfig.xml and optionally the catalog
- CompareEnd types of the catalog against the known end types and connection rules
- CompleteMissing end codes and rules by connection type and counterpart
- OutputModified files with a list of changes
Standards & codes
Reference: the assistant follows Autodesk's file structure and the connection types of these standards. Standard texts and standard tables are not included.
| Autodesk Plant 3D | Structure of EndCodesConfig.xml and DefaultConnectorsConfig.xml (Autodesk standard as template) |
|---|---|
| DIN 11851, DIN 11864-1, DIN 32676 | Examples of threaded fittings and clamp connections in the standard rules |
Data & origin
| Standard configuration | Autodesk standard files of the respective Plant 3D version |
|---|---|
| Suggestions for connecting parts | ASEING practice from spec creation |
Assumptions & limits
- Back up both files before replacing them; close Plant 3D while swapping.
- Customer-specific end types with the same name for different connection types are reported but not resolved automatically.